Reducing crosstalk in optically-pumped magnetometer arrays.

Optically pumped magnetometers (OPMs) operating in the spin-exchange relaxation-free regime are emerging as alternative sensors to superconducting quantum interference devices (SQUIDs) for magnetoencephalography (MEG). As the number of OPMs in a single imaging system increases to rival SQUID MEG systems, cross-talk between nearby sensors limits the measurement accuracy. We experimentally demonstrate a coil geometry, which generates an order of magnitude less cross-talk (less than 0.5%) than a Helmholtz coil (8%). The new coil design is simple and compact, requiring two coaxial coil pairs that add 1 mm to the 6 mm radius and is driven by a single current driver. The new design maintains a magnetic field homogeneity over the volume of the magnetometer of more than 94%, which is sufficient for the zero-field OPM to operate in a 200 nT ambient field environment. Our result increases the feasibility of high-spatial resolution OPM-based bio-magnetic imaging technology due to the reduction of cross-talk at high sensor density.

Sports hernias: experience in a sports medicine center.

PURPOSE: Chronic pain of the inguino-crural region or "pubalgia" explains the 0.5-6.2% of the consultations by athletes. Recently, areas of weakness in the posterior wall called "sports hernias," have been identified in some of these patients, capable of producing long-standing pain. Several authors use different image methods (CT, MRI, ultrasound) to identify the lesion and various techniques of repair, by open or laparoscopic approaches, have been proposed but there is no evidence about the superiority of one over others due to the difficulty for randomizing these patients. In our experience, diagnosis was based on clinical and ultrasound findings followed by laparoscopic exploration to confirm and repair the injury. The present study aims to assess the performance of our diagnostic and therapeutic management in a series of athletes affected by "pubalgia". METHODS: 1450 athletes coming from the orthopedic office of a sport medicine center were evaluated. In 590 of them (414 amateur and 176 professionals) sports hernias were diagnosed through physical examination and ultrasound. We performed laparoscopic "TAPP" repair and, thirty days after, an assessment was performed to determine the evolution of pain and the degree of physical activity as a sign of the functional outcome. We used the U Mann-Whitney test for continuous scale variables and the chi-square test for dichotomous variables with p < 0.05 as a level of significance. RESULTS: In 573 patients ultrasound examination detected some protrusion of the posterior wall with normal or minimally dilated inguinal rings, which in 498 of them coincided with areas affected by pain. These findings were confirmed by laparoscopic exploration that also diagnosed associated contralateral (30.1%) and ipsilateral defects, resulting in a total of 1006 hernias. We found 84 "sport hernias" in 769 patients with previous diagnosis of adductor muscle strain (10.92%); on the other hand, in 127 (21.52%) of our patients with "sport hernias" US detected concomitant injuries of the adductor longus tendon, 7 of which merited additional surgical maneuvers (partial tenotomy). Compared with the findings of laparoscopy, ultrasound had a sensitivity of 95.42% and a specificity of 100%; the positive and negative predictive values were 100 and 99.4% respectively. No postoperative complications were reported. Only seven patients suffered recurrence of pain (successful rate: 98.81%); the ultrasound ruled out hernia recurrence, but in three cases it diagnosed tendinitis of the rectus abdominis muscle. CONCLUSIONS: Our series reflects the multidisciplinary approach performed in a sports medicine center in which patients are initially evaluated by orthopedic surgeons in order to discard the most common causes of "pubalgia". "Sports hernias" are often associated with adductor muscle strains and other injuries of the groin allowing speculate that these respond to a common mechanism of production. We believe that, considering the difficulty to design randomized trials, only a high coincidence among the diagnostic and therapeutic instances can ensure a rational health care.

Validation of Prediction Equations of Energy Values of a Single Ingredient or Their Combinations in Male Broilers.

A set of prediction equations to estimate the nitrogen-corrected apparent metabolizable energy (AMEn) of individual ingredients and diets used in the poultry feed industry was evaluated. The AMEn values of three energy ingredients (maize, sorghum and defatted maize germ meal), four protein ingredients (soybean meal, maize gluten meal 60% crude protein, integral micronized soy and roasted whole soybean) and four diets (three containing four feedstuffs, complex diets, and one containing only corn-soybean meal, basal diet) were determined using a metabolism assay with male broilers from 1 to 7, 8 to 21, 22 to 35, and 36 to 42 days old. These values were compared to the AMEn values presented in the tables of energy composition or estimated by equation predictions based on chemical composition data of feedstuffs. In general, the equation predictions more precisely estimated the AMEn of feedstuffs when compared to the tables of energy composition. The equation AMEn (dry matter [DM] basis) = 4,164.187+51.006 ether extract (% in DM basis)-197.663 ash-35.689 crude fiber (% in DM basis)-20.593 neutral detergent fiber (% in DM basis) (R(2) = 0.75) was the most applicable for the prediction of the energy values of feedstuffs and diets used in the poultry feed industry.

Glyceryl trinitrate for chronic anal fissure--healing or headache? Results of a multicenter, randomized, placebo-controled, double-blind trial.

PURPOSE: Internal anal sphincterotomy for treating chronic anal fissure can irreversibly damage anal continence. Reversible chemical sphincterotomy may be achieved by anal application of glyceryl trinitrate ointment (nitric oxide donor), which has been reported to heal the majority of patients with anal fissure by inducing sphincter relaxation and improving anodermal blood flow. This trial aimed to further clarify the role of glyceryl trinitrate in the treatment of chronic anal fissure. METHODS: A total of 132 consecutive patients from nine centers were randomly assigned to receive 0.2 percent glyceryl trinitrate ointment or placebo twice daily for at least four weeks. The severity of pain and maximum anal resting pressure were measured before and after one week of treatment. Anodermal blood flow was measured before and after application of glyceryl trinitrate or placebo in ten patients. RESULTS: The study was completed by 119 patients (59 glyceryl trinitrate and 60 placebo), matched for gender, age, duration of symptoms, duration of treatment, site of fissure, previous attempts to treat, pain score, and maximum anal resting pressure. Twenty-nine patients (49.2 percent) healed after glyceryl trinitrate and 31 patients (51.7 percent) healed after placebo (P = not significant). Pain score fell significantly in both groups, in addition to maximum anal resting pressure. Anodermal blood flow improved significantly in seven patients receiving glyceryl trinitrate, but not in the three receiving placebo. Twenty-three patients (33.8 percent) experienced headache and 4 (5.9 percent), orthostatic hypotension after glyceryl trinitrate. CONCLUSION: This trial fails to demonstrate any superiority of topical 0.2 percent glyceryl trinitrate treatment vs. a placebo, although the effects of glyceryl trinitrate on anodermal blood flow and sphincter pressure are confirmed. This finding, together with the high incidence of side-effects, should discourage the use of this treatment as a substitute for surgery in chronic anal fissure.

[Treatment of large laparoceles. A simplified radical method and the use of intra-abdominal synthetic prostheses]. / Trattamento dei grandi laparoceli. Metodologia di radicalità semplificata, impiego di protesi sintetica intraddominale.

Having defined the terms of the problem of treating large incisional hernias with regard to the state of the patient and the anatomical conditions of the abdominal wall, the paper outlines the criteria for the execution of radical surgery which, while taking into account the numerous variables, simplify the overall surgical treatment. The efficacy of the prosthesis used, which ranges from a wide intra-abdominal polypropylene net, a well tolerated material, to the simplest plastic prosthesis for the muscle-aponeurotic wall, is confirmed by the excellent results achieved in the first difficult cases operated.