Determination of the Scalar and Vector Polarizabilities of the Cesium 6s

Using recent high-precision measurements of electric dipole matrix elements of atomic cesium, we make an improved determination of the scalar (α) and vector (ß) polarizabilities of the cesium 6s^{2}S_{1/2}→7s^{2}S_{1/2} transition calculated through a sum-over-states method. We report values of α=-268.82(30)a_{0}^{3} and ß=27.139(42)a_{0}^{3} with the highest precision to date. We find a discrepancy between our value of ß and the past preferred value, resulting in a significant shift in the value of the weak charge Q_{w} of the cesium nucleus. Future work to resolve the differences in the polarizability will be critical for interpretation of parity nonconservation measurements in cesium, which have implications for physics beyond the standard model.

The d 3Π state of LiRb.

We report our spectroscopic studies of the d 3Π state of ultra-cold 7Li85Rb using resonantly enhanced multi-photon ionization and depletion spectroscopy with bound-to-bound transitions originating from the metastable a 3Σ+ state. We evaluate the potential of this state for use as the intermediate state in a stimulated-Raman-adiabatic-passage transfer scheme from triplet Feshbach LiRb molecules to the X 1Σ+ ground state and find that the lowest several vibrational levels possess the requisite overlap with initial and final states, as well as convenient energies. Using depletion measurements, we measured the well depth and spin-orbit splitting. We suggest possible pathways for short-range photoassociation using deeply bound vibrational levels of this electronic state.

A unified theory of bone healing and nonunion: BHN theory.

This article presents a unified clinical theory that links established facts about the physiology of bone and homeostasis, with those involved in the healing of fractures and the development of nonunion. The key to this theory is the concept that the tissue that forms in and around a fracture should be considered a specific functional entity. This 'bone-healing unit' produces a physiological response to its biological and mechanical environment, which leads to the normal healing of bone. This tissue responds to mechanical forces and functions according to Wolff's law, Perren's strain theory and Frost's concept of the "mechanostat". In response to the local mechanical environment, the bone-healing unit normally changes with time, producing different tissues that can tolerate various levels of strain. The normal result is the formation of bone that bridges the fracture - healing by callus. Nonunion occurs when the bone-healing unit fails either due to mechanical or biological problems or a combination of both. In clinical practice, the majority of nonunions are due to mechanical problems with instability, resulting in too much strain at the fracture site. In most nonunions, there is an intact bone-healing unit. We suggest that this maintains its biological potential to heal, but fails to function due to the mechanical conditions. The theory predicts the healing pattern of multifragmentary fractures and the observed morphological characteristics of different nonunions. It suggests that the majority of nonunions will heal if the correct mechanical environment is produced by surgery, without the need for biological adjuncts such as autologous bone graft. Cite this article: Bone Joint J 2016;98-B:884-91.

Ilizarov management of Schatzker IV to VI fractures of the tibial plateau: 105 fractures at a mean follow-up of 7.8 years.

This study aimed to determine the long-term functional, clinical and radiological outcomes in patients with Schatzker IV to VI fractures of the tibial plateau treated with an Ilizarov frame. Clinical, functional and radiological assessment was carried out at a minimum of one year post-operatively. A cohort of 105 patients (62 men, 43 women) with a mean age of 49 years (15 to 87) and a mean follow-up of 7.8 years (1 to 19) were reviewed. There were 18 type IV, 10 type V and 77 type VI fractures. All fractures united with a mean time to union of 20.1 weeks (10.6 to 42.3). No patient developed a deep infection. The median range of movement (ROM) of the knee was 110(°) and the median Iowa score was 85. Our study demonstrates good long-term functional outcome with no deep infection; spanning the knee had no detrimental effect on the ROM or functional outcome. High-energy fractures of the tibial plateau may be treated effectively with a fine wire Ilizarov fixator.

Formation of ultracold (7)Li(85)Rb molecules in the lowest triplet electronic state by photoassociation and their detection by ionization spectroscopy.

We report the formation of ultracold (7)Li(85)Rb molecules in the a(3)Σ(+) electronic state by photoassociation (PA) and their detection via resonantly enhanced multiphoton ionization (REMPI). With our dual-species Li and Rb magneto-optical trap apparatus, we detect PA resonances with binding energies up to ∼62 cm(-1) below the (7)Li 2s (2)S1/2 + (85)Rb 5p (2)P1/2 asymptote. In addition, we use REMPI spectroscopy to probe the a(3)Σ(+) state and excited electronic 3(3)Π and 4(3)Σ(+) states and identify a(3)Σ(+) (v″ = 7-13), 3(3)Π (vΠ' = 0-10), and 4(3)Σ(+) (vΣ' = 0-5) vibrational levels. Our line assignments agree well with ab initio calculations. These preliminary spectroscopic studies on previously unobserved electronic states are crucial to discovering transition pathways for transferring ultracold LiRb molecules created via PA to deeply bound rovibrational levels of the electronic ground state.

Freehand 'figure 4' technique for tibial intramedullary nailing: introduction of technique and review of 87 cases.

Intramedullary nailing of tibial fractures is commonplace, and freehand operative techniques are increasingly popular. The standard freehand method has the knee of the injured leg flexed over a radiolucent bolster. This requires the theatre fluoroscope to swing from antero-posterior to lateral position several times. Furthermore, guide wire placement, reaming and nail insertion are all performed well above most surgeons' shoulder height. Alternatively the leg is hung over the edge of the table, and the assistant must crouch and hold the leg until the nail is passed beyond the fracture. We describe a freehand figure 4 position technique for tibial nailing which is easier both for the surgeons and the radiographer, and present a series of 87 consecutive cases utilising this method.

Simultaneous augmentation cystoplasty and cuff only artificial urinary sphincter in children and young adults with neurogenic urinary incontinence.

PURPOSE: We review our experience with artificial urinary sphincter and augmentation cystoplasty in patients with neurogenic bladder. This is the largest known series to specifically evaluate cuff only artificial urinary sphincter at augmentation cystoplasty. MATERIALS AND METHODS: A total of 18 males underwent simultaneous artificial urinary sphincter and augmentation cystoplasty at our institution between 1982 and 2012, of whom 13 (72%) underwent cuff only artificial urinary sphincter. Outcomes included urinary continence, emptying modality, artificial urinary sphincter status, complications and additional procedures. RESULTS: Of the patients undergoing augmentation cystoplasty and cuff only artificial urinary sphincter 10 (77%) were initially continent. Average time of continence was 52.9 months. Four patients (31%) required no additional procedures and remained continent. Urinary incontinence developed in 3 patients (23%) immediately postoperatively and in 6 (46%) subsequently. Ultimately 9 patients (69%) required conversion to complete artificial urinary sphincter at a mean of 36.9 months postoperatively. Overall 12 patients (92%) were continent at followup. There were no artificial sphincter specific complications in patients undergoing the cuff only procedure with conversion to complete artificial urinary sphincter. After conversion to complete artificial urinary sphincter 3 patients (23%) experienced artificial sphincter specific complications. Reoperation was performed in 10 patients (77%), for 13 total procedures (1.3 per patient). There were no complications with cuff only artificial urinary sphincter and 6 complications with complete artificial urinary sphincter (p = 0.025). Finally, patients undergoing cuff only artificial urinary sphincter requiring revision were younger than those not requiring revision (15.6 vs 30.8 years, p = 0.026). CONCLUSIONS: Simultaneous cuff only artificial urinary sphincter and augmentation cystoplasty appears safe and efficacious in patients with neurogenic bladder, with fewer complications than complete artificial urinary sphincter, and may provide definitive urinary continence in up to a third of patients. This procedure is technically easy, allows for outpatient revision, provides time for the child to mature and may be cost effective in avoiding placement of additional components in this select patient population.

Impact of radiotherapy on surgical repair and outcome in patients with rectourethral fistula.

AIM: Most patients presenting with rectourethral fistula acquire it as a complication of radiotherapy for prostate cancer, as a result of injury to the rectum during prostatectomy, through trauma or from Crohn's disease. This study examined whether choice of operation and results of surgery for rectourethral fistula are influenced by prior radiotherapy. METHOD: Male patients undergoing surgery for rectourethral fistula were identified from a prospectively maintained database. Data regarding aetiology, surgical treatment and outcomes were analysed. RESULTS: Fifty patients (median age = 65.5 years) were identified. Radiation was received by 29 patients for prostate or rectal cancer, and 21 patients developed a fistula following prostatectomy, Crohn's disease or pelvic fracture (without radiation). Prior to definitive surgery, 30 patients underwent fecal diversion and 37 underwent urinary diversion. In total, 57 repairs were performed (44 patients had one repair, five patients had two and one patient had three). Definitive surgery was approached predominantly abdominally in radiated patients (90.6 vs 9.3%, P < 0.001) and perineally in nonradiated patients (80 vs 20%, P < 0.001). Successful primary fistula repair was more frequent in the nonradiated group compared with the radiated group (80.9 vs 0%, P < 0.001). Permanent colostomy and urinary diversion were more often required in radiated patients than in nonradiated patients (colostomy: 83 vs 0%, P < 0.001; urorostomy: 100 vs 19%, P < 0.001). CONCLUSION: Few patients with radiation-induced rectourethral fistula avoid permanent colostomy and urostomy. In contrast, most patients with nonradiation-related fistulae undergo successful perineal repair without permanent faecal and urinary diversion.

Accuracy of surface landmark identification for cannula cricothyroidotomy.

Cannula cricothyroidotomy is recommended for emergency transtracheal ventilation by all current airway guidelines. Success with this technique depends on the accurate and rapid identification of percutaneous anatomical landmarks. Six healthy subjects underwent neck ultrasound to delineate the borders of the cricothyroid membrane. The midline and bisecting transverse planes through the membrane were marked with an invisible ink pen which could be revealed with an ultraviolet light. Eighteen anaesthetists were then invited to mark an entry point for cricothyroid membrane puncture. Only 32 (30%) attempts by anaesthetists accurately marked the skin area over the cricothyroid membrane. Of these only 11 (10%) marked over the centre point of the membrane. Entry point accuracy was not significantly affected by subjects' weight, height, body mass index, neck circumference or cricothyroid dimensions. Consultant and registrar anaesthetists were significantly more accurate than senior house officers at correctly identifying the cricothyroid membrane. Accuracy of percutaneously identifying the cricothyroid membrane was poor. Ultrasound may assist in identifying anatomical landmarks for cricothyroidotomy.

A prospective trial comparing the Holland nail with the dynamic hip screw in the treatment of intertrochanteric fractures of the hip.

We compared the outcome of patients treated for an intertrochanteric fracture of the femoral neck with a locked, long intramedullary nail with those treated with a dynamic hip screw (DHS) in a prospective randomised study. Each patient who presented with an extra-capsular hip fracture was randomised to operative stabilisation with either a long intramedullary Holland nail or a DHS. We treated 92 patients with a Holland nail and 98 with a DHS. Pre-operative variables included the Mini Mental test score, patient mobility, fracture pattern and American Society of Anesthesiologists grading. Peri-operative variables were anaesthetic time, operating time, radiation time and blood loss. Post-operative variables were time to mobilising with a frame, wound infection, time to discharge, time to fracture union, and mortality. We found no significant difference in the pre-operative variables. The mean anaesthetic and operation times were shorter in the DHS group than in the Holland nail group (29.7 vs 40.4 minutes, p < 0.001; and 40.3 vs 54 minutes, p < 0.001, respectively). There was an increased mean blood loss within the DHS group versus the Holland nail group (160 ml vs 78 ml, respectively, p < 0.001). The mean time to mobilisation with a frame was shorter in the Holland nail group (DHS 4.3 days, Holland nail 3.6 days, p = 0.012). More patients needed a post-operative blood transfusion in the DHS group (23 vs seven, p = 0.003) and the mean radiation time was shorter in this group (DHS 0.9 minutes vs Holland nail 1.56 minutes, p < 0.001). The screw of the DHS cut out in two patients, one of whom underwent revision to a Holland nail. There were no revisions in the Holland nail group. All fractures in both groups were united when followed up after one year. We conclude that the DHS can be implanted more quickly and with less exposure to radiation than the Holland nail. However, the resultant blood loss and need for transfusion is greater. The Holland nail allows patients to mobilise faster and to a greater extent. We have therefore adopted the Holland nail as our preferred method of treating intertrochanteric fractures of the hip.

[Management of vaginal vault prolapse repair with robotically-assisted laparoscopic sacrocolpopexy]. / Traitement du prolapsus du dôme vaginal par sacrocolpopexie laparoscopique assistée par robot.

Transabdominal sacrocolpopexy offers an excellent definitive treatment option for patients with high grade vaginal vault prolapse with long-term success rates ranging from 93-99%. However, because it is a transabdominal procedure it is associated with increased morbidity compared with vaginal repairs. We describe a novel minimally invasive technique of vaginal vault prolapse repair and present out initial experience. The surgical technique involves placement of five laparoscopic ports: three for the Da Vinci robot and two for the assistant. A polypropylene mesh is then attached to the sacral promontory and to the vaginal apex using Gortex sutures. At the end of the case, the mesh material is the covered by the peritoneum. We also present our initial experience with this technique in 18 consecutive patients. The analysis focused on complications, urinary continence, patient satisfaction, and morbidity. Follow-up was conducted by provider-patient interview. Twenty-five patients underwent a robotic-assisted laparoscopic sacrocolpopexy at our institution in the past 24 months for severe symptomatic vaginal vault prolapse. 10/25 (40%) underwent a concomitant anti-incontinence procedure. Mean follow-up was 5. (1-12) months and mean age was 66 (47-82) years. Mean total operative time was 3.2 (2.25-4.75) hours. One patient had to be converted to an open procedure secondary to unfavorable anatomy. All but one patient were discharged from the hospital after an overnight stay; one patient left on postoperative day #2. Complications were limited to mild port site infections in two patients, which resolved with oral antibiotic therapy. One patient developed recurrent grade 3 rectocele, but had no evidence of cystocele or enterocele. We present a novel technique for vaginal vault prolapse repair that combines the advantages of open sacrocolpopexy with the decreased morbidity and improved cosmesis of laparoscopic surgery. It is associated with decreased hospital stay, low complication and conversion rates, and high patient satisfaction. While our early experience is encouraging, long-term data is needed to confirm these findings and establish longevity of the repair.

Atomic homodyne detection of weak atomic transitions.

We have developed a two-color, two-pathway coherent control technique to detect and measure weak optical transitions in atoms by coherently beating the transition amplitude for the weak transition with that of a much stronger transition. We demonstrate the technique in atomic cesium, exciting the 6s(2)S(1/2) --> 8s(2)S(1/2) transition via a strong two-photon transition and a weak controllable Stark-induced transition. We discuss the enhancement in the signal-to-noise ratio for this measurement technique over that of direct detection of the weak transition rate, and project future refinements that may further improve its sensitivity and application to the measurement of other weak atomic interactions.

Observation of the phase lag in the asymmetric photoelectron angular distributions of atomic barium.

We have observed and measured the phase lag in the phase-dependent variation of the asymmetric photoelectron angular distribution of atomic barium. For these measurements, we photoionize the 6s6p(1)P(1) intermediate state of barium with concurrent one-photon and two-photon (omega-2omega) interactions. The laser interactions ionize the atoms in the vicinity of the series of autoionizing states converging upon the 5d(2)D(5/2) threshold. We study the variation of the phase lag as a function of the laser frequency. The variation shows strong correlation to the location of the autoionizing resonances, with full range exceeding 2pi, confirming the critical role of these resonances.

Is a fat stitch required when closing a hip hemiarthroplasty wound without a drain?

Studies have shown no benefit of a subcutaneous fat stitch when closing hip wounds, but all have been in the presence of a drain. Our aim was to determine whether, in the absence of a drain, suturing or not of the subcutaneous fat layer in hip hemiarthroplasty wounds had any significant effect on wound complication rate. We performed a prospective cohort study of 45 hip hemiarthroplasty patients who had a fat stitch and 40 who did not. No drains were used in either group. There were 44 patients in the fat stitch group and 35 in the no fat stitch group after six patients were excluded. The infection rate was 2% for the fat stitch group, and 20% for the no fat stitch group (p=0.02). There were no cases of deep dehiscence in the fat stitch group, but four cases (11%) in the no fat stitch group (p=0.035). The overall complication rate in the fat stitch group was 6.8% compared to 33% in the no fat stitch group (p=0.007). In the absence of a drain, we have found a significant increase in hip hemiarthroplasty wound complications when the subcutaneous fat is not sutured.

Fragility fractures of the ankle: stabilisation with an expandable calcaneotalotibial nail.

Fragility fractures of the ankle occur mainly in elderly osteoporotic women. They are inherently unstable and difficult to manage. There is a high incidence of complications with both non-operative and operative treatment. We treated 12 such fractures by closed reduction and stabilisation using a retrograde calcaneotalotibial expandable nail. The mean age of patients was 84 years (75 to 95). All were women and were able to walk fully weight-bearing after surgery. There were no wound complications. One patient died from a myocardial infarction 24 days after surgery. The 11 other patients were followed up for a mean of 67 weeks (39 to 104). All the fractures maintained satisfactory alignment and healed without delay. Six patients refused removal of the nail after union of the fracture. The functional rating using the scale of Olerud and Molander gave a mean score at follow-up of 61, compared with a pre-injury value of 70.

Determination of the phase difference between even and odd continuum wave functions in atoms through quantum interference measurements.

We establish a technique for the determination of the phase difference between even and odd parity continuum wave functions in atoms. This determination is based upon our detailed measurements of a quantum mechanical interference between two photoionization processes using a two-color laser field. We present our measurement of the phase difference between the continuum p and d waves in atomic rubidium, which is in good agreement with the expected value.

Is nephroureterectomy necessary in all cases of upper tract transitional cell carcinoma? Long-term results of conservative endourologic management of upper tract transitional cell carcinoma in individuals with a normal contralateral kidney.

OBJECTIVES: To evaluate the endoscopic management of upper urinary tract transitional cell carcinoma (TCC) as a first-line treatment in patients with a normal contralateral kidney. METHODS: During an 11-year period, 21 patients diagnosed with upper tract TCC were treated with conservative endourologic techniques using either neodymium:yttrium-aluminum-garnet laser or electrocautery at our institution. The 21 patients were followed up for a mean of 6.1 years (range 1 to 11.6). RESULTS: A total of 8 renal pelvic tumors and 13 ureteral tumors were found. All tumors were Stage T1 or less and grade 3 or less. All tumors were less than 2 cm in the greatest dimension (range 0.4 to 2). Of the 21 patients, 7 (33%) had one local recurrence and 1 (4.7%) developed two local recurrences. Of the 13 ureteral tumors, 6 (46%) recurred; 1 (12%) of the 8 renal pelvic tumors recurred. No recurrent tumor was shown to have an increase in grade. Of the 21 target renal units, 17 (81%) were preserved; 4 (19%) of 21 patients required nephroureterectomy because of tumor recurrence. Overall, 11 patients in the series died, 10 of non-TCC etiology and 1 secondary to invasive bladder TCC that developed after treatment for upper tract TCC. No patients died as a result of conservative management of their upper tract TCC. CONCLUSIONS: Endourologic techniques and conservative treatment of upper tract TCC is an evolving field; however, in properly selected patients, endoscopic treatment can be safely and effectively used as a first-line treatment for upper tract TCC.

Does nocturnal deactivation of the artificial urinary sphincter lessen the risk of urethral atrophy?

OBJECTIVES: To compare nocturnal deactivation with nocturnal activation of the artificial urinary sphincter (AUS) to determine whether nocturnal deactivation reduces the risk of urethral atrophy and subsequent recurrent incontinence. To the best of our knowledge, no review comparing these two approaches has been performed. METHODS: At the Mayo Clinic, all patients are instructed to deactivate their AUS at night; at Baylor, all patients keep their AUS activated all the time. At each institution, a group of consecutive men with comparable severe urinary incontinence after radical retropubic prostatectomy were selected; 61 and 46 patients from the Mayo Clinic and Baylor, respectively, were available for review. All Mayo Clinic patients strictly adhered to nocturnal deactivation of their AUS and all 46 patients from Baylor kept their AUS activated at all times, except during voiding. Each patient was reviewed for the long-term risk of subsequent reoperation, especially regarding recurrent incontinence due to urethral atrophy. RESULTS: Seventeen (27.8%) of the 61 patients from Mayo (mean follow-up 40 months) required a repeated operation. Of the 17 AUS failures, 6 (35%) were due to urethral atrophy. Of the 46 patients from Baylor (mean follow-up 28 months), 16 (34.7%) required a repeated operation. Of the 16 AUS failures, 10 (62%) were due to urethral atrophy. Overall, the patients who nocturnally deactivated their AUS had a 10% risk of atrophy-related incontinence compared with a 21% risk in the nocturnally activated group. CONCLUSIONS: Although not statistically significant, nocturnal deactivation appears to decrease the risk of urethral atrophy and recurrent incontinence (10% versus 21%). Nocturnal deactivation should be considered in men who are dry at night and have sufficient motivation to lessen the risk of urethral atrophy secondary to cuff compression.