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We review the optical phonon dispersions of graphene. In particular, we focus on the presence of two Kohn anomalies in the highest optical phonon branch at the $\bf \Gamma$and $\bf K$points of the Brillouin zone. We then show how graphene can be used as a model for the calculation of phonons in carbon nanotubes. Finally, we present the beyond Born-Oppenheimer corrections to their phonon dispersions. These are experimentally revealed in the Raman spectra of doped samples.

Intravesical hyaluronic acid (HA) and chondroitin sulphate (CS) instillation are effective for urinary tract infections (UTIs) and bladder pain syndrome. This study aimed to evaluate the tolerability, safety and efficacy of intravesical HA and CS instillation in patients with late radiation tissue cystitis (LRTC). In this pilot study, tolerability was reported as discontinuation or deviation of the protocol, safety as general or local side effects, efficacy as improvement of bladder capacity and frequency, quality of life (QoL) through the European Quality of Life 5-Dimensions (EQ-5D) (details at http://www.controlled-trials.com/ISRCTN37534393). Thirty-two patients with LRTC were enrolled. Twenty-seven patients (84.8%) received a mean of 12.2±0.3 months of instillation therapy. Only two patients (6.2%) developed a urinary tract infection from instillation, which required antibiotic treatment, nevertheless not compromising the therapy schedule. No male patient developed a urethral stricture. Intravesical instillation was associated with a significant increase (>50%) of bladder capacity from baseline (66.9ml) both at 3 months (101.9ml; p<0.001) and 12 months (174.4 ml; p<0.001). EQ-5D index significantly increased from baseline to both 3 and 12 months (0.26, 0.69 and 0.96, respectively; p<0.001). Intravesical co-administration of HA and CS improved bladder function, symptoms and QoL in patients with LRTC.

This investigative pilot study was conducted with the objective of evaluating the therapeutic effect of a cream containing hyaluronic acid (HA) and silver-sulfadiazine (Altergen®, IBSA Farmaceutici Italia, S.r.l.) in adult patients undergoing two-stage urethroplasty using an oral mucosal graft for anterior urethral strictures due to failed hypospadias repair. We used a cream (Altergen®) containing the following active ingredients: 100 g HA, 0.20 mg sodium salt, and 1 g silver-sulfadiazine. During the period of January 2009 - May 2010, 40 patients, mean age 24 years, who had undergone hypospadias surgery during childhood were enrolled in the study, according to some inclusion and exclusion criteria (age >18 years, with the absence of diabetes, neurovascular disease, lichen sclerosus or other dermatological lesions). All 40 patients had navicularis or penile urethral strictures and underwent two-stage urethroplasty using an oral mucosa graft. Post-operatively, 20 patients (50%) were treated with a cream containing HA and silver-sulfadiazine (Altergen®) and 20 patients (50%) were treated using a standard topical treatment (iodopovidone 10% gel). All patients underwent a follow-up at 6, 15, 30, 60 and 120 days after surgery. Out of the 20 patients treated with the HA and silver-sulfadiazine-containing cream (Altergen®), 18 (90%) showed good and complete healing of the graft implant 30 days after surgery. Of the 20 patients not treated with the HA and silver-sulfadiazine-contaning cream (Altergen®), 13 (65%) showed good and complete healing of the graft implant 30 days after surgery. These results were constant in all follow-ups in both patient groups. In patients who underwent a navicularis or penile two-stage oral mucosal graft urethroplasty, the use of a HA and silver-sulfadiazine-containing cream was associated with a higher success rate of the graft implant and a lower incidence of post-surgical complications compared to the controls.

Objectives To illustrate the history and the evolution over time of bulbar dorsal onlay urethroplasty, comparing outcomes when using buccal mucosa or skin grafts.Materials and Methods Ninety-four patients underwent bulbar urethral reconstruction using two dorsal onlay techniques, namely augmented anastomotic urethroplasty and dorsal onlay graft urethroplasty. Preoperative evaluation included clinical history, physical examination, urine culture, residual urine measurement, uroflowmetry and urethrography. Thirty-four patients underwent augmented anastomotic urethroplasty using penile skin (10 cases) or buccal mucosa (24 cases) grafts. Sixty patients underwent dorsal onlay graft urethroplasty using penile skin (38 cases) or buccal mucosa (22 cases) grafts. Forty-eight out of 94 patients received skin grafts and 46 buccal mucosal grafts.Results Sixty-four (68%) out of 94 cases were successful, whereas 30 (32%) failed. The 34 augmented anastomotic urethroplasties provided successful outcomes in 24 cases (70.6%), but poor outcomes in 10 (29.4%) cases. The 60 dorsal onlay graft urethroplasty proved to be successful in 42 cases (70%), failing in 18 (30%) cases. Twenty-eight (58.3%) out of 48 penile skin grafts were successful and 20 (41.7%) failed. Thirty-six (78.3%) out of 46 buccal mucosa grafts were successful and 10 (21.7%) failed. The 30 failed cases were then treated with internal urethrotomy in 14 cases (46.7%), perineal urethrostomy in 8 cases (26.7%), two-stage repair in 4 cases (13.3%), and one-stage repair in 4 cases (13.3%).Conclusions The dorsal onlay technique used for bulbar urethral stricture repair has changed over time. In our experience, the buccal mucosa seems to be the best substitute graft material for bulbar urethroplasty using dorsal approach.

Abstract.: We review the optical phonon dispersions of graphene. In particular, we focus on the presence of two Kohn anomalies in the highest optical phonon branch at the $\bf \Gamma$ and $\bf K$ points of the Brillouin zone. We then show how graphene can be used as a model for the calculation of phonons in carbon nanotubes. Finally, we present the beyond Born-Oppenheimer corrections to their phonon dispersions. These are experimentally revealed in the Raman spectra of doped samples.

We review the optical phonon dispersions of graphene. In particular, we focus on the presence of two Kohn anomalies in the highest optical phonon branch at the ? and K points of the Brillouin zone. We then show how graphene can be used as a model for the calculation of phonons in carbon nanotubes. Finally, we present the beyond Born-Oppenheimer corrections to their phonon dispersions. These are experimentally revealed in the Raman spectra of doped samples.

Chronic stimulation of the sacral nerves has now become one of the most accepted stimulation therapies for functional lower urinary tract symptoms refractory to conservative treatment. Despite the existence of a large amount of literature on sacral neuromodulation (SNM) showing a fairly high percent of significant improvement in clinical outcome there are few experimental studies of SNM stimulus parameters and/or neurophysiological monitoring. We evaluated the specific action of SNM on the primary sensory cortical area. Somatosensory evoked potentials (SEPs) of the pudendal and posterior tibial nerves were evaluated in patients implanted with a monolateral permanent quadripolar electrode.

Purpose: Present therapeutic approaches to control bladder pain are clinically and scientifically unsatisfactory, and pain in the lower urinary tract remains a challenge even to the skilled urologist. A randomized placebo controlled study was done to evaluate intravesical capsaicin for severe bladder pain. Followup was 6 months. Materials and Methods: A total of 36 patients was prospectively randomized into those receiving 10 micromolar intravesical capsaicin twice weekly for 1 month (group 1) or placebo (group 2). All patients had pelvic pain for at least 6 months, and had no urinary tract infection within the last 3 months, functional disorders of the lower urinary tract, or other vesical or urethral pathology. Pretreatment voiding pattern and pain score were recorded. Patients were evaluated immediately at the end of treatment (primary end point) and 6 months later (secondary end point). Results: Both groups were adequately homogenous with regard to age, sex ratio, duration of disease, voiding pattern and pain score. At both end points group 1 had significant improvement in frequency and nocturia but no improvement in urgency. No change was noted in group 2. A significant decrease in pain score was found in group 1 at the primary (mean plus or minus standard deviation 3.22 plus/minus 0.42, p less than 0.01) and secondary (3.83 plus/minus 0.47, p less than 0.01) end points compared to before treatment (5.61 plus/minus 0.40, chi-square with 2 degrees of freedom 29.25, p less than 0.0001). A significant improvement was also observed in the placebo group, in which the pretreatment pain score (5.47 plus/minus 0.37) was decreased at the primary (4.47 plus/minus 0.36, p less than 0.01) and secondary (4.48 plus/minus 0.34, p less than 0.01, chi-square with 2 degrees of freedom 12.71, p less than 0.002) end points. There were no statistically significant differences between the 2 groups. Conclusions: We confirmed the beneficial effect of intravesical instillation of capsaicin on voiding pattern in patients with hypersensitive disorders (frequency and nocturia). We could not confirm improvement in pain score after capsaicin treatment compared to placebo. Possibly a larger dose of capsaicin would be more effective in controlling pain and neurological disease of the bladder.

There have been only a few reports on the involvement of the urinary tract in patients with systemic sclerosis, a disease of the connective tissue characterized by thickening and fibrosis of the skin, abnormality of the small arteries, and involvement of the gastrointestinal tract, heart, lung and kidney. We report the urodynamic assessment and histological examination of 9 women with scleroderma. Three patients voided less than 100 ml. with a significant residual volume and 4 presented with detrusor areflexia during a filling cystometrogram. Histopathological examination in all patients with detrusor areflexia demonstrated the presence of arterial lesions and derangement of the capillary bed of the detrusor musculature. Our data provide evidence for the functional and histological involvement of the bladder in patients with systemic sclerosis.

We update our interim results of bulbar urethroplasty using a skin graft placed on the dorsal urethral surface.

The dose limiting factor for 131I therapy in patients with thyroid cancer is myelotoxicity, thus an accurate determination of radioiodine activity in the red marrow is of paramount importance. The reference method for red marrow dosimetry in radiometabolic therapy is based on the measurement of radioiodine kinetics, particularly the activity/time curve in blood. Such a measurement requires withdrawal of blood samples at various times after 131I administration. This procedure involves some potential risk from the radiation protection point of view, such as possible contamination of personnel with blood and disposal of the radioactive blood samples (and syringes). We present here a minimally invasive method to evaluate radioiodine kinetics in the blood, which only requires one blood sample and a set of measurements on the patient's thigh made with a collimated NaI(Tl) probe. The method has been validated in four patients treated with 131I for thyroid cancer.

Substantial reduction in the thyroid volume (up to 70-80%) after 131I therapy of Graves' disease has been demonstrated and reported in the literature. Recently a mathematical model of thyroid mass reduction during the first month after therapy has been developed and a new algorithm for the radiation committed dose calculation has been proposed. Reduction of the thyroid mass and the radiation committed dose to the gland depend on a parameter k, defined for each subject. The calculation of k allows the prediction of the activity to administer, depending on the radiation committed dose chosen by the physician. In this paper a method for calculating k is proposed. The calculated values of k are compared to values derived from measurements of the changes in thyroid mass in twenty-six patients treated by 131I for Graves' disease. The radiation committed dose to the thyroid can be predicted within 21%, and the radioiodine activity to administer to the patient can be predicted within 22% using the calculated values of k. The thyroid volume reduction during the first month after therapy administration can be also predicted with good accuracy using the calculated values of k. The radiation committed dose and the radioiodine activity to administer were calculated using a new, very simple algorithm. A comparison between the values calculated by this new algorithm and the old, classical Marinelli-Quimby algorithm shows that the new method is more accurate.

Thermoluminescence dosemeters (TLD) are widely used to monitor personal doses due to photon fields in the radiation protection of workers. For these low dose range applications it is essential to decide whether a single TLD retains an occupational air kerma value above background or not. In other words, it is important to determine the detection limit LD and the determination limit LQ of the whole dosimetric system. LD is the smallest value of air kerma that can be detected at a specified confidence level, LQ is the minimum value of air kerma that can be measured with a given precision. ICRP 60 recommends an annual dose limit of 1 mSv for the public. Thus it is possible to take this value as the limit between public and exposed workers, as recommended by the European Community Directive and corresponding local laws. Therefore if NLD(t), the annual detection limit of the TLD system, is considerably less than 1 mSv, TLD evaluation can also be used to decide whether a worker can be considered exposed or not. N is the number of annual TLD readings, LD is the detection limit of the TLD system. Both N and LD depend on the monitoring interval time t. The dependence of LD and LQ on the background radiation level and on the monitoring intervals, i.e. on N, is investigated. Assuming that the background air kerma level is approximately constant, it can be shown that the shorter the time of exposure, the higher the annual detection limit. Furthermore, if one considers an annual dose limit of 1 mSv, LD is seen to be greater than the recording level Lr for short exposure times and the system is not able to evaluate it. A set of 15 TLD-100(LiF: Mg, Ti) dosimetric cards and a Harshaw 6000 TLD automatic card reader have been used in order to determine LD and LQ. It has been found that an increase of the monitoring time t from 30 to 180 days leads to a reduction of the annual detection limit from 0.32 � 0.10 mGy to 0.100 � 0.030 mGy. For t <180 days the recording level Lr is less than LD; for t <45 days the investigation level Li is less than LD.