Extremal curves in nilpotent Lie groups

We classify extremal curves in free nilpotent Lie groups. The classification is obtained via an explicit integration of the adjoint equation in Pontryagin Maximum Principle. It turns out that abnormal extremals are precisely the horizontal curves contained in algebraic varieties of a specific type. We also extend the results to the nonfree case.Comment: 30 pages, final versio

Non-minimality of corners in subriemannian geometry

We give a short solution to one of the main open problems in subriemannian geometry. Namely, we prove that length minimizers do not have corner-type singularities. With this result we solve Problem II of Agrachev's list, and provide the first general result toward the 30-year-old open problem of regularity of subriemannian geodesics.Comment: 11 pages, final versio

Influence of Light Stress on the Accumulation of Xanthophylls and Lipids in Haematococcus pluvialis CCALA 1081 Grown under Autotrophic or Mixotrophic Conditions

The influence of light stress and trophic environmental conditions on the production of astaxanthin, other xanthophylls and lipids from an Argentinian strain of Haematococcus pluvialis was investigated. Microalgae cultures were incubated for two weeks in autotrophic or mixotrophic conditions (with sodium acetate in the culture medium) and subjected to two different light stresses. HPLC analyses showed that: 1) regardless of the growth conditions, microalgal cells accumulated most of the astaxanthin (about 90%) in esterified form; 2) maximal increase of astaxanthin level was observed in the culture grown in autotrophic conditions subjected to moderate light stress (90 μmol photons m-2 s-1), while the same light regime in mixotrophic conditions led to a lower increase (only 25.8 fold); 3) in the case of high light stress (350 μmol photons m-2 s-1), the adaptive response of microalgae also led to a significant increase in the amount of astaxanthin both in autotrophic (22 fold increase) and in mixotrophic (16 fold increase) conditions; 4) an inverse correlation (R2 = 0.977) exists between the amount of lipids and that of astaxanthin accumulated by Haematococcus grown under different growth conditions; 5) lutein was found to be the most accumulated pigment in microalgae not subjected to light stress.Fil: Doria, Enrico. University of Pavia. Department of Biology and Biotechnology; ItaliaFil: Temporiti, Marta Elisabetta E.. University of Pavia. Department of Biology and Biotechnology; ItaliaFil: Damiani, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Popovich, Cecilia Angelines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Leonardi, Patricia Ines. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Nielsen, Erik. University of Pavia. Department of Biology and Biotechnology; Itali

Type III pleuropulmonary blastoma in a 7-month-old female baby with impending respiratory failure: a case report

INTRODUCTION: Pleuropulmonary blastoma is a very rare, aggressive, embryonal pulmonary neoplasm which mostly affects children under the age of 5. According to the histopathological features, three subtypes of pleuropulmonary blastoma have been recognized: type I (purely cystic), type II (grossly visible cystic and solid elements) and type III (purely solid). Characteristics of type I and type II blastoma allow an earlier diagnosis compared with type III. Here we present a case report of an unusual presentation of type III pleuropulmonary blastoma. CASE PRESENTATION: We describe the case of a 7-month-old female baby of Italian mother and Kurdish father who was diagnosed with type III pleuropulmonary blastoma, which entirely occupied her right hemithorax. CONCLUSIONS: The reported case is an unusual presentation because type III pleuropulmonary blastoma typically occurs in older children. The complete re-expansion of her residual, previously totally compressed, right lung observed immediately after the resection of the lesion suggests an atypical rapid growth of this embryonal tumor in the late phase of gestation or after delivery. This case report suggests that, in addition to other childhood tumors, type III pleuropulmonary blastoma should be included in the differential diagnosis of solid nonhomogeneous thoracic large masses, compressing the mediastinal and chest wall structures in infants. This is an original case report of interest for several specialities such us pediatrics, radiology, surgery and oncology

Relapses of traumatic peroneal tendons subluxation already treated surgically: a new surgical approach

Aim To illustrate the surgical treatment of relapses of traumatic peroneal tendons subluxation. Methods We came across a young woman, who sustained a sprain in her dominant ankle after a trauma; we noticed subluxation of the peroneal tendons during eversion and extension of the foot. She referred to a previous accident some years before with peroneal tendon subluxation treated by superior peroneal retinaculum (SPR) sutures with a synthetic braided absorbable material. We prescribed conventional radiography, magnetic resonance imaging (MRI) and performed surgery: we removed scar tissue, reattached the retinaculum using suture anchors strengthening it with an acellular dermal matrix allograft patch. Results Periodic clinical follow-ups until 24 months were performed evaluating the stability of the ankle, checking the range of movement, and the Visual Analogic Scale (VAS) and American Orthopedic Foot and Ankle Society Score (AOFAS) was administered. At the first check the subluxation was resolved and the ankle was stable. The VAS scale had the value of 0 at the 3-month follow-up maintained until the final check. Conclusion Relapsing traumatic peroneal tendons subluxation is rare, as well as the possibility of a re-intervention years later. This technique seems to guarantee an excellent result even in the long term, allowing resolution of pain and joint stability. In fact, the use of acellular dermal patch is an already commonly described technique for the augmentation in rotator cuff and hip capsular repair; no reports are available in literature in relation to the use of graft for the repair of the superior peroneal retinaculum

MMR vaccine in the postpartum does not expose seronegative women to untoward effects.

Contesto : Lo scopo di questo studio è stato quello di valutare se la vaccinazione rosolia immediatamente dopo il parto potrebbe esporre le donne sieronegative per effetti indesiderati specifici.Metodi : 163 donne rosolia-sieronegativi hanno ricevuto il vaccino MMR nel periodo post-partum; sono stati valutati a 1 mese a 3 mesi successivi attraverso interviste telefoniche. Come controlli, abbiamo confrontato 163 donne rosolia-sieropositivi, che potrebbe avere sintomi simili per qualsiasi motivo, nello stesso arco di tempo.Risultati : A un mese di follow-up, 161 donne nel gruppo dei casi e 162 controlli hanno risposto alla nostra intervista telefonica; alle tre mesi di follow-up, 154 casi e 159 controlli. Eruzione cutanea, faringite, artralgia, linfoadenopatia cervicale, mialgia e parestesia sono state le lamentele più frequentemente riportati in entrambi i gruppi. Una differenza statisticamente significativa nella frequenza di linfoadenopatia cervicale e rash cutaneo a un mese (p = 0.028 ep = 0.005, rispettivamente) è stata osservata tra i casi ei controlli; Tuttavia, nessuna differenza significativa è stata ancora osservata nella frequenza delle manifestazioni muscoloscheletriche acute e croniche a tre mesi.Conclusioni : Non sono sostanziali differenze sono stati segnalati tra casi e controlli per quanto riguarda la frequenza di artralgia e conseguente mialgia al MMR vaccinazione in post-partum . Postpartum rosolia la vaccinazione è sicura e consigliabile in caso di necessità per evitare la circolazione del virus e la sindrome da rosolia congenita

Human beta-defensin 4 expression in Gianotti-Crosti Syndrome

The Gianotti-Crosti syndrome is a relatively common children dermatosis characterized by a monomorphus erythematous papular rash limited to the face and extensor surface of the arms and legs. Although the pathogenesis is still unclear, infections are considered as the most important factor. Human b-defensins are cationic antimicrobial peptides closely related to bacterial and viral infections of many epithelia. We herein report a case of Gianotti-Crosti syndrome in a 7 year-old Caucasian girl presented with a prominent eruption, consisting of dome-shaped lichenoid papules on her upper and lower extremities, with a spontaneous resolution. Skin biopsy revealed a dense lichenoid lymphohistiocytic infiltrate and showed strong cytoplasmic immunopositivity for human b-defensin-4 in the stratum corneum, stratum granulosum, and stratum spinosum. Considering that b-defensins have been described to be induced by infections, we investigated the expression of human b-defensin-4 by immunohistochemistry in a case of Gianotti-Crosti syndrome, in order to demonstrate that it represents a cutaneous response to skin infections. </p

In-flight calibration and verification of the Planck-LFI instrument

In this paper we discuss the Planck-LFI in-flight calibration campaign. After a brief overview of the ground test campaigns, we describe in detail the calibration and performance verification (CPV) phase, carried out in space during and just after the cool-down of LFI. We discuss in detail the functionality verification, the tuning of the front-end and warm electronics, the preliminary performance assessment and the thermal susceptibility tests. The logic, sequence, goals and results of the in-flight tests are discussed. All the calibration activities were successfully carried out and the instrument response was comparable to the one observed on ground. For some channels the in-flight tuning activity allowed us to improve significantly the noise performance.Comment: Long technical paper on Planck LFI in flight calibration campaign: 109 pages in this (not final) version, 100 page in the final JINST versio