Pressure Sensing Based on Nonconventional Air-Guiding Transmission Windows in Hollow-Core Photonic Crystal Fibers

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Non-conventional core-guided transmission windows within the visible spectral range are identified in commercial hollow-core photonic crystal fibers designed to operate at 1550 nm. These windows are likely to be related to higher-order cladding photonic bandgaps and are found to be highly dependent on the cladding microstructure, thus being affected by pressure-induced stress/deformation. 20-cm-long fiber samples are then used to demonstrate simple and temperature-independent hydrostatic pressure sensing with two different setups. While in the first setup pressure is externally applied to the fiber and results in operation in the hundreds of kgf/cm(2) (or tens of MPa) range, the second setup applies pressure directly to fiber internal microstructure and is sensitive to pressures down to a fraction of kgf/cm(2) (hundredths of MPa). The fact that pressure is directly transduced into transmitted power greatly simplifies the required sensor interrogation setup.271116051609Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CAPES [0156/05-1

Polymeric additives to enhance the functional properties of calcium phosphate cements

The vast majority of materials used in bone tissue engineering and regenerative medicine are based on calcium phosphates due to their similarity with the mineral phase of natural bone. Among them, calcium phosphate cements, which are composed of a powder and a liquid that are mixed to obtain a moldable paste, are widely used. These calcium phosphate cement pastes can be injected using minimally invasive surgery and adapt to the shape of the defect, resulting in an entangled network of calcium phosphate crystals. Adding an organic phase to the calcium phosphate cement formulation is a very powerful strategy to enhance some of the properties of these materials. Adding some water-soluble biocompatible polymers in the calcium phosphate cement liquid or powder phase improves physicochemical and mechanical properties, such as injectability, cohesion, and toughness. Moreover, adding specific polymers can enhance the biological response and the resorption rate of the material. The goal of this study is to overview the most relevant advances in this field, focusing on the different types of polymers that have been used to enhance specific calcium phosphate cement properties

Acinic Cell Carcinoma with Extensive Neuroendocrine Differentiation: A Diagnostic Challenge

Primary salivary gland carcinoma with neuroendocrine differentiation is of rare occurrence, especially so in the parotid gland. Amongst the various reported primary tumors with neuroendocrine differentiation, acinic cell carcinoma (ACC) one such tumor. A 48 year old lady presented with a gradually increasing right infra-auricular swelling for a period of 1 year which enlarged suddenly in a short period. Contrast Enhanced Computed Tomography (CECT) suggested diagnosis of Pleomorphic Adenoma. Fine Needle Aspiration Cytology (FANC) yielded a cystic fluid suggesting a possibility of Warthin’s tumor or Oncocytic lesion. Intraoperative findings were suggestive of a Warthin’s tumor. Initial histopathological examination of the tumor was suggestive of neuroendocrine carcinoma. However, extensive sectioning revealed peripheral islands of ACC. Immunoexpression of S-100, Neuron specific Enolase (NSE), Chromogranin A and Synaptophysin confirmed the diagnosis. The possibility of neuroendocrine differentiation in a primary salivary gland tumor should be kept in mind whenever a salivary gland tumor shows only neuroendocrine histology

Intercomparison of the northern hemisphere winter mid-latitude atmospheric variability of the IPCC models

We compare, for the overlapping time frame 1962-2000, the estimate of the northern hemisphere (NH) mid-latitude winter atmospheric variability within the XX century simulations of 17 global climate models (GCMs) included in the IPCC-4AR with the NCEP and ECMWF reanalyses. We compute the Hayashi spectra of the 500hPa geopotential height fields and introduce an integral measure of the variability observed in the NH on different spectral sub-domains. Only two high-resolution GCMs have a good agreement with reanalyses. Large biases, in most cases larger than 20%, are found between the wave climatologies of most GCMs and the reanalyses, with a relative span of around 50%. The travelling baroclinic waves are usually overestimated, while the planetary waves are usually underestimated, in agreement with previous studies performed on global weather forecasting models. When comparing the results of various versions of similar GCMs, it is clear that in some cases the vertical resolution of the atmosphere and, somewhat unexpectedly, of the adopted ocean model seem to be critical in determining the agreement with the reanalyses. The GCMs ensemble is biased with respect to the reanalyses but is comparable to the best 5 GCMs. This study suggests serious caveats with respect to the ability of most of the presently available GCMs in representing the statistics of the global scale atmospheric dynamics of the present climate and, a fortiori, in the perspective of modelling climate change.Comment: 39 pages, 8 figures, 2 table

Congenital cystic eye with multiple dermal appendages: a case report

BACKGROUND: A partial or complete failure in the involution of the primary optic vesicle resulting in the formation of a cyst is an extremely rare anomaly known as congenital cystic eye. The primary optic vesicle is formed but instead of the anterior part of the vesicle involuting to lie in apposition with the posterior part, a cyst persists at birth and replaces the eye. CASE PRESENTATION: We report a case of congenital cystic eye associated with multiple dermal appendages in a 1-day-old female child. This condition presented at birth as a large orbital mass in the left orbit that bulged forwards and stretched the eyelids. No globe or any other ocular structures were identified in the orbit. Multiple dermal appendages were present in the adjacent part of the face below the left orbit and on the upper part of the neck. CONCLUSIONS: Congenital cystic eye is an extremely rare condition and with only 28 previous cases reported in the literature. We present the second case of congenital cystic eye with multiple dermal appendages of the face and neck

Adenocarcinoma arising in a heterotopic pancreas (Heinrich type III): a case report

<p>Abstract</p> <p>Introduction</p> <p>Heterotopic pancreatic cancer in the duodenum is a very rare disease. Only twelve cases have been reported worldwide to date. We report a rare case of malignant transformation of heterotopic pancreas (Heinrich type III) in the duodenum with long-term survival of the patient, and review the 12 cases in the literature.</p> <p>Case presentation</p> <p>A 75-year-old Japanese man was admitted to our hospital complaining of nausea and vomiting. Endoscopy and upper gastrointestinal contrast study showed marked duodenal stenosis. A pylorus-preserving pancreaticoduodenectomy was performed. Histopathological examination of the surgically resected specimen showed malignant transformation of heterotopic pancreas (Heinrich type III) in the duodenum. The postoperative course was uneventful, and the patient was discharged from the hospital on postoperative day 30. He is well and shows no signs of recurrence at the time of writing, six years after the surgery.</p> <p>Conclusion</p> <p>Adenocarcinoma arising within the heterotopic pancreas appears to be rare. It is difficult to obtain a correct diagnosis preoperatively. The management of heterotopic pancreas depends on the presence or absence of symptoms. If the patient is asymptomatic or benign, conservative treatment with regular follow-up is recommended. When the patient is symptomatic or there is a suspicion of malignancy, surgical management with intra-operative frozen section diagnosis is indicated.</p

Ferromagnetic Semiconductors: Moving Beyond (Ga,Mn)As

The recent development of MBE techniques for growth of III-V ferromagnetic semiconductors has created materials with exceptional promise in spintronics, i.e. electronics that exploit carrier spin polarization. Among the most carefully studied of these materials is (Ga,Mn)As, in which meticulous optimization of growth techniques has led to reproducible materials properties and ferromagnetic transition temperatures well above 150 K. We review progress in the understanding of this particular material and efforts to address ferromagnetic semiconductors as a class. We then discuss proposals for how these materials might find applications in spintronics. Finally, we propose criteria that can be used to judge the potential utility of newly discovered ferromagnetic semiconductors, and we suggest guidelines that may be helpful in shaping the search for the ideal material.Comment: 37 pages, 4 figure

PAK1 Protein Expression in the Auditory Cortex of Schizophrenia Subjects

Deficits in auditory processing are among the best documented endophenotypes in schizophrenia, possibly due to loss of excitatory synaptic connections. Dendritic spines, the principal post-synaptic target of excitatory projections, are reduced in schizophrenia. p21-activated kinase 1 (PAK1) regulates both the actin cytoskeleton and dendritic spine density, and is a downstream effector of both kalirin and CDC42, both of which have altered expression in schizophrenia. This study sought to determine if there is decreased auditory cortex PAK1 protein expression in schizophrenia through the use of quantitative western blots of 25 schizophrenia subjects and matched controls. There was no significant change in PAK1 level detected in the schizophrenia subjects in our cohort. PAK1 protein levels within subject pairs correlated positively with prior measures of total kalirin protein in the same pairs. PAK1 level also correlated with levels of a marker of dendritic spines, spinophilin. These latter two findings suggest that the lack of change in PAK1 level in schizophrenia is not due to limited sensitivity of our assay to detect meaningful differences in PAK1 protein expression. Future studies are needed to evaluate whether alterations in PAK1 phosphorylation states, or alterations in protein expression of other members of the PAK family, are present in schizophrenia

Effect of Oxidative Stress on Homer Scaffolding Proteins

Homer proteins are a family of multifaceted scaffolding proteins that participate in the organization of signaling complexes at the post-synaptic density and in a variety of tissues including striated muscle. Homer isoforms form multimers via their C-terminal coiled coil domains, which allows for the formation of a polymeric network in combination with other scaffolding proteins. We hypothesized that the ability of Homer isoforms to serve as scaffolds would be influenced by oxidative stress. We have found by standard SDS-PAGE of lysates from adult mouse skeletal muscle exposed to air oxidation that Homer migrates as both a dimer and monomer in the absence of reducing agents and solely as a monomer in the presence of a reducing agent, suggesting that Homer dimers exposed to oxidation could be modified by the presence of an inter-molecular disulfide bond. Analysis of the peptide sequence of Homer 1b revealed the presence of only two cysteine residues located adjacent to the C-terminal coiled-coil domain. HEK 293 cells were transfected with wild-type and cysteine mutant forms of Homer 1b and exposed to oxidative stress by addition of menadione, which resulted in the formation of disulfide bonds except in the double mutant (C246G, C365G). Exposure of myofibers from adult mice to oxidative stress resulted in decreased solubility of endogenous Homer isoforms. This change in solubility was dependent on disulfide bond formation. In vitro binding assays revealed that cross-linking of Homer dimers enhanced the ability of Homer 1b to bind Drebrin, a known interacting partner. Our results show that oxidative stress results in disulfide cross-linking of Homer isoforms and loss of solubility of Homer scaffolds. This suggests that disulfide cross-linking of a Homer polymeric network may contribute to the pathophysiology seen in neurodegenerative diseases and myopathies characterized by oxidative stress