Predictions for Nongaussianity from Nonlocal Inflation

In our previous work the nonlinearity parameter f_NL, which characterizes nongaussianity in the cosmic microwave background, was estimated for a class of inflationary models based on nonlocal field theory. These models include p-adic inflation and generically have the remarkable property that slow roll inflation can proceed even with an extremely steep potential. Previous calculations found that large nongaussianity is possible; however, the technical complications associated with studying perturbations in theories with infinitely many derivatives forced us to provide only an order of magnitude estimate for f_NL. We reconsider the problem of computing f_NL in nonlocal inflation models, showing that a particular choice of field basis and recent progress in cosmological perturbation theory makes an exact computation possible. We provide the first quantitatively accurate computation of the bispectrum in nonlocal inflation, confirming our previous claim that it can be observably large. We show that the shape of the bispectrum in this class of models makes it observationally distinguishable from Dirac-Born-Infeld inflation models.Comment: 26 pages, 5 figures; references added, sign convention for f_NL clarified, minor correction

The treatment of pectus excavatum: Results of a mininvasive surgical technique on the first 50 patients

Aim. Pectus excavatum is the commonest thoracic congenital malformation, but its treatment remains not well known. The authors present the results of the mini-invasive repair at G. Gaslini Institute of Genoa, Italy. Methods. Nuss mini-invasive repair avoids anterior scars. The correction is achieved by the introduction under thoracoscopy of a retrosternal curve bar that is rotated by 180°. Postoperatory pain is managed by an epidural catheter. In all the operated patients we evaluated the clinical pre-operatory parameters (Spirometrie, radiological and cardiological data), the surgical details and the results. Results. Fifty patients were operated, 43 of them males, ranging from 7 and 22 years of age, with an average of 17 years of age. Only 8 of them were asymptomatic and required surgery for psychological reasons. The 74% presented some stress dyspnea. Some impairment in spirometric parameters were observed in 28% and mitral valve prolapse in 30%. The only significant intraoperative complication was a bleeding from a thoracic wall vessel that required a left emergency minimal thoracotomy. Postoperative complications were: 2 pneumothorax (drained for 24 hours), 2 transitory pulmonary atelectasis, 1 hemothorax in a patient with coagulation deficit, 3 wound problems (1 infection and 2 hematomas). The esthetical score after surgery, according to the patients, was 9.15 on average, in a scale from 1 to 10. None rated less than 7. The pain score with the same scale was rated 6.8 on average. Conclusion. The Nuss technique is safe and guarantees very satisfactory esthetical results

Lymphatic damage in venous surgery

Purpose: Before a lower limb surgical operation due to venous disease, it is necessary to immediately evaluate the presence and seriousness of the concurrent lymphatic deficiency. Methods: Besides objective test that can reveal a clinically evident lymphatic deficiency, it is helpful to investigate family and remote pathological anamnesis to identify possible risk factors or specific family propensities. As far as instrumental tests are concerned, it is advisable to perform both a doppler ultrasonographic examination and a limb segmentary Lymphoscintigraphy. The most risky area is the inguinal one, where lymphatic collector vessels join main lymph-nodal structures. Obviously, lesions of these structures may start a lymphatic deficiency, but it is also important to underline that scar reactions and relevant fibrosis, that may characterize an even normal post-operation period, may create a further obstacle to normal lymphatic drain. Results and Conclusions: Special attention has to be paid to precise indications and venous surgery technique in mixed clinical situations, when both venous and lymphatic systems are involved, to avoid potential clinical state worsening. Finally, diagnostic and therapeutical prevention modalities for possible lymphatic injuries in CVI affected limbs have to be kept into consideration, up to microsurgical technique application. Hopefully therefore, with the purpose of a correct preventive and not invasive surgical operation, more an more attention will be paid regarding potential lymphatic impairment derived from venous surgery

Intersecting kinematic encoding and readout of intention in autism

Observers with autism spectrum disorders (ASDs) find it difficult to read intentions from movements. However, the computational bases of these difficulties are unknown. Do these difficulties reflect an intention readout deficit, or are they more likely rooted in kinematic (dis-)similarities between typical and ASD kinematics? We combined motion tracking, psychophysics, and computational analyses to uncover single-trial intention readout computations in typically developing (TD) children (n = 35) and children with ASD (n = 35) who observed actions performed by TD children and children with ASD. Average intention discrimination performance was above chance for TD observers but not for ASD observers. However, single-trial analysis showed that both TD and ASD observers read single-trial variations in movement kinematics. TD readers were better able to identify intention-informative kinematic features during observation of TD actions; conversely, ASD readers were better able to identify intention-informative features during observation of ASD actions. Crucially, while TD observers were generally able to extract the intention information encoded in movement kinematics, those with autism were unable to do so. These results extend existing conceptions of mind reading in ASD by suggesting that intention reading difficulties reflect both an interaction failure, rooted in kinematic dissimilarity between TD and ASD kinematics (at the level of feature identification), and an individual readout deficit (at the level of information extraction), accompanied by an overall reduced sensitivity of intention readout to single-trial variations in movement kinematics