Opto-Mechanics of deformable Fabry-Perot Cavities

We investigated the opto-mechanical properties of a Fabry-Perot cavity with a mirror mounted on a spring. Such a structure allows the cavity length to change elastically under the effect of light induced forces. This opto-mechanical coupling is exploited to control the amplitude of mechanical fluctuation of the mirror. We present a model developed in the classical limit and discuss data obtained in the particular case for which photo-thermal forces are dominant.Comment: 26 pages, 7 figure

Bilateral reconstruction of the mandibular body with symphyseal preservation using a single fibula free flap: operative technique

Background: Mandibular osteonecrosis may occur in 5% of the patients who undergo radiotherapy for the treatment of head and neck malignancies. Resection and microvascular reconstruction is the treatment of choice in complicated osteoradionecrosis, however multifocal presentation may complicate the management of the disease given the poor quality and limited availability of adequate recipient vessels. Operative technique: A 74-year-old man affected by multifocal severe osteoradionecrosis of the mandible underwent bilateral resection of the mandibular bodies while preserving the symphysis. The defects were reconstructed with a single fibula flap composed by two bony segments connected by a central segment, corresponding to the symphyseal region, in which the bone was dissected and removed. The anastomosis was performed on a single side of the neck. Healing was uneventful and the adopted technique allowed for a quick functional and esthetic recovery. Conclusion: The presented technique provided a safe and efficacious, although technically challenging, solution in a case presenting multifocal osteonecrosis of the jaw. The morbidity of the procedure was limited because the tissue resection and reconstruction processes were minimized. Graphical Abstract: [Figure not available: see fulltext.

Folded Radial Forearm Free Flap for the Reconstruction of Total Soft Palate Defects: Operative Technique

Background: The surgical plan to reconstruct the palate must be carefully prepared given the morphological peculiarity of the soft palate forming both the roof of the mouth and the floor of the nasal cavity. This article focuses on the use of folded radial forearm free flaps to manage isolated defects of the soft palate in the absence of tonsillar pillar involvement. Methods: Three patients affected by squamous cell carcinoma of the palate underwent resection of the soft palate and immediate reconstruction with a folded radial forearm free flap. Results: All three patients showed good short-term morphological-functional outcomes as far as swallowing, breathing, and phonation were concerned. Conclusions: The folded radial forearm free flap seems to be an efficacious way to manage localized defects of the soft palate, given the positive outcomes of the three patients treated, and in accordance with other authors. In general, the radial forearm free flap was confirmed to be a versatile solution for those intraoral defects of the soft tissue requiring a limited quantity of volume as in the case of the soft palate

Jacobsen syndrome and neonatal bleeding: report on two unrelated patients

Introduction: In 1973, Petrea Jacobsen described the first patient showing dysmorphic features, developmental delay and congenital heart disease (atrial and ventricular septal defect) associated to a 11q deletion, inherited from the father. Since then, more than 200 patients have been reported, and the chromosomal critical region responsible for this contiguous gene disorder has been identified. Patients’ presentation: We report on two unrelated newborns observed in Italy affected by Jacobsen syndrome (JBS, also known as 11q23 deletion). Both patients presented prenatal and postnatal bleeding, growth and developmental delay, craniofacial dysmorphisms, multiple congenital anomalies, and pancytopenia of variable degree. Array comparative genomic hybridization (aCGH) identified a terminal deletion at 11q24.1-q25 of 12.5 Mb and 11 Mb, in Patient 1 and 2, respectively. Fluorescent in situ hybridization (FISH) analysis of the parents documented a de novo origin of the deletion for Patient 1; parents of Patient 2 refused further genetic investigations. Conclusions: Present newborns show the full phenotype of JBS including thrombocytopenia, according to their wide 11q deletion size. Bleeding was particularly severe in one of them, leading to a cerebral hemorrhage. Our report highlights the relevance of early diagnosis, genetic counselling and careful management and follow-up of JBS patients, which may avoid severe clinical consequences and lower the mortality risk. It may provide further insights and a better characterization of JBS, suggesting new elements of the genotype-phenotype correlations

Efeito de diferentes temperaturas na sobrevivência e no crescimento de mudas de guanandi (Calophyllum brasiliense Cambess.).

São muitas as necessidades e as justificativas para o reflorestamento utilizando essências florestais nativas, especialmente com árvores de uso múltiplo em monocultivo ou em sistemas agroflorestais, visando, entre outros, à produção de madeiras nobres. O guanandi, uma espécie nativa, que fornece madeira de boa qualidade e ótimo valor econômico, tem sido muito utilizado neste sentido e, por muitas vezes, cultivado em condições climáticas desfavoráveis e/ou prejudiciais ao desenvolvimento da espécie. Neste trabalho objetivou-se avaliar as conseqüências de diferentes temperaturas na sobrevivência e no crescimento de mudas de guanandi (Calophyllum brasiliense Cambess.). O experimento foi conduzido no laboratório de Fisiologia Vegetal da Embrapa Gado de Corte, em Campo Grande, MS, de março até maio de 2009. Utilizaram-se mudas de guanandi, com seis meses de idade, que foram transplantadas para recipientes plásticos de 500 mL, contendo substrato comercial e solução nutritiva completa. Após aclimatação em temperatura constante de 27ºC, as mudas foram submetidas a três regimes de temperatura: 27/17ºC, 17/10ºC e 10/6ºC, durante 50 dias, em câmara climática do tipo B.O.D., com fotoperíodo de 12 horas. O delineamento experimental foi de blocos casualizados, com quatro tratamentos e cinco repetições, sendo que cada repetição foi constituída de cinco plantas. Avaliou-se a sobrevivência das plantas (%), a altura (cm) e o diâmetro do colo (mm), as taxas de fotossíntese (μmol/m²/s) e a condutância estomática (μmol/m²/s). Os melhores resultados, para todas as variáveis mensuradas, foram obtidos para as plantas submetidas à temperatura entre 27/17ºC. Para as plantas submetidas às temperaturas 27/17ºC e 17/10ºC obteve-se 100% de sobrevivência. Pode-se concluir que a temperatura afeta a sobrevivência e o crescimento do guanandi, porque a espécie se mostrou intolerante ao regime de temperatura 10/6ºC, de modo que ao final do experimento houve morte das plantas

Decoration of nanovesicles with pH (low) insertion peptide (pHLIP) for targeted delivery

Acidity at surface of cancer cells is a hallmark of tumor microenvironments, which does not depend on tumor perfusion, thus it may serve as a general biomarker for targeting tumor cells. We used the pH (low) insertion peptide (pHLIP) for decoration of liposomes and niosomes. pHLIP senses pH at the surface of cancer cells and inserts into the membrane of targeted cells, and brings nanomaterial to close proximity of cellular membrane. DMPC liposomes and Tween 20 or Span 20 niosomes with and without pHLIP in their coating were fully characterized in order to obtain fundamental understanding on nanocarrier features and facilitate the rational design of acidity sensitive nanovectors. The samples stability over time and in presence of serum was demonstrated. The size, ζ-potential, and morphology of nanovectors, as well as their ability to entrap a hydrophilic probe and modulate its release were investigated. pHLIP decorated vesicles could be useful to obtain a prolonged (modified) release of biological active substances for targeting tumors and other acidic diseased tissues

Uso de produtos naturais para proteção de mudas na arborização de pastagens.

Os sistemas de produção convencional têm esgotado os recursos ambientais, o que torna o agroecossistema frágil e insustentável. Sistemas silvipastoris podem ser alternativas viáveis na recuperação de pastagens degradadas. Este estudo foi desenvolvido com o objetivo de avaliar produtos naturais na implantação de espécies arbóreas em pastagens com presença constante de bovinos, sem proteção física das mudas. O experimento foi conduzido na Embrapa Gado de Corte, Campo Grande, MS, no período de 02/02/2005 a 28/03/2005. O delineamento utilizado foi de parcelas subdivididas inteiramente ao acaso, com dez repetições. As parcelas foram: 1) fezes bovinas ao redor da muda, 2) sangue bovino seco, 3) ovo sem casca e 4) testemunha sem proteção. As subparcelas foram cinco especies arbóreas: Myroxylon peruiferum (Bálsamo), Dipteryx alata (Cumbaru), Schizolobium parahyba (Guapuruvu), Genipa americana (Jenipapo) e Mimosa caesalpineaefolia (Sansão do campo). A herbivoria foi intensa em todos os tratamentos. A S. parahyba apresentou taxa de sobrevivência de 72,5%, enquanto 100% das plantas da M. caesalpineafolia morreram. Há indícios de que a maior proteção, embora parcial, foi dada pela aplicação de fezes ao redor da muda. As aspersões de sangue ou de ovo não ofereceram proteção às árvores jovens. A concentração e a freqüência de aplicação das fezes é uma alternativa que merece maiores estudos

Carba-D,L-allal- and -D,L-galactal-derived vinyl N-nosyl aziridines as useful tools for the synthesis of 4-deoxy-4-(N-nosylamino)-2,3-unsaturated-5a-carbasugars

The novel carba-D,L-allal- and carba-D,L-galactal-derived vinyl N-nosyl aziridines were prepared and the regio- and stereoselective behavior in opening reactions with O- and N-nucleophiles examined. The carbaglycosylating ability of the novel aziridines, as deduced by the amount of 1,4-addition products (1,4-regioselectivity) obtained in the acid-catalyzed methanolysis taken as a model reaction, is similar or superior to that observed with the corresponding carba-D,L-allal- and -D,L-galactal-derived vinyl epoxides, respectively. In all 1,2- and 1,4-addition products obtained, a –(N-nosylamino) group is regio- and stereoselectively introduced at the C(4) carbon of a 1,2- or 2,3-unsaturated carbasugar, susceptible to further elaborations toward aminocyclitol derivatives. The stereoselective synthesis of the corresponding, enantiomerically pure carba-D,L-allal- and -D,L-galactal-derived vinyl N-acetyl aziridines is also described

Building a biomimetic membrane for neutron reflectivity investigation : complexity, asymmetry and contrast

The preparation and investigation of model membranes is deserving growing interest both for the physics of complex systems, and for biology. The need of simplified models should preserve mimicking the qualifying characteristics of biological membranes, and keep non-invasive and detailed description. As a main feature, biological membranes are non-homogeneous in the disposition of components, both in the lateral and in the transverse direction. We prepared asymmetric supported membranes containing GM1 ganglioside in biomimetic proportion according to different protocols. Then, we studied their internal structure by neutron reflectometry, providing few-Angstrom sensitivity in the cross direction meanwhile avoiding radiation damage. This technique can also be profitably applied to study interactions at the membrane surface. The best protocol has proven to be the Langmuir-Blodgett/Langmuir-Schaefer depositions. Notably, also the simpler and most accessible protocol of vesicle fusion was found to be suitable for straightforward and good quality deposition of compositionally asymmetric membranes

Uso da espectroscopia de refletância no infravermelho próximo visando uma análise discriminatória de diferentes cultivares do gênero Paspalum.

Editado por Ana Rita de Araújo Nogueira, Simone Cristina Méo Niciur