11 resultados para valuation of new technology-based start ups
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
The article aims to analyze the process of knowledge creation in Brazilian technology-based companies, using as a background the driving and restrictive factors found in this process. As the pillars of discussion, four main modes of knowledge conversion were used, according to the Japanese model: socialization, externalization, combination and internalization. The comparative case method through qualitative research was carried out in nine technology-based enterprises that had been incubated or have recently passed through the stage of incubation (so-called graduated companies) in the Technology Park of Sao Carlos, state of Sao Paulo, Brazil. Among the main results, the combination of knowledge was identified as more conscious and structured in graduated companies, in relation to incubated companies. In contrast, it was noted that incubated companies have an environment with greater opportunities for socialization, internalization and externalization of knowledge.
Resumo:
Background/purpose: Gallstones and cholelithiasis are being increasingly diagnosed in children owing to the widespread use of ultrasonography. The treatment of choice is cholecystectomy, and routine intraoperative cholangiography is recommended to explore the common bile duct. The objectives of this study were to describe our experience with the management of gallstone disease in childhood over the last 18 years and to propose an algorithm to guide the approach to cholelithiasis in children based on clinical and ultrasonographic findings. Methods: The data for this study were obtained by reviewing the records of all patients with gallstone disease treated between January 1994 and October 2011. The patients were divided into the following 5 groups based on their symptoms: group 1, asymptomatic; group 2, nonbiliary obstructive symptoms; group 3, acute cholecystitis symptoms; group 4, a history of biliary obstructive symptoms that were completely resolved by the time of surgery; and group 5, ongoing biliary obstructive symptoms. Patients were treated according to an algorithm based on their clinical, ultrasonographic, and endoscopic retrograde cholangiopancreatography (ERCP) findings. Results: A total of 223 patients were diagnosed with cholelithiasis, and comorbidities were present in 177 patients (79.3%). The most common comorbidities were hemolytic disorders in 139 patients (62.3%) and previous bariatric surgery in 16 (7.1%). Although symptoms were present in 134 patients (60.0%), cholecystectomy was performed for all patients with cholelithiasis, even if they were asymptomatic; the surgery was laparoscopic in 204 patients and open in 19. Fifty-six patients (25.1%) presented with complications as the first sign of cholelithiasis (eg, pancreatitis, choledocolithiasis, or acute calculous cholecystitis). Intraoperative cholangiography was indicated in 15 children, and it was positive in only 1 (0.4%) for whom ERCP was necessary to extract the stone after a laparoscopic cholecystectomy (LC). Preoperative ERCP was performed in 11 patients to extract the stones, and a hepaticojejunostomy was indicated in 2 patients. There were no injuries to the hepatic artery or common bile duct in our series. Conclusions: Based on our experience, we can propose an algorithm to guide the approach to cholelithiasis in the pediatric population. The final conclusion is that LC results in limited postoperative complications in children with gallstones. When a diagnosis of choledocolithiasis or dilation of the choledocus is made, ERCP is necessary if obstructive symptoms persist either before or after an LC. Intraoperative cholangiography and laparoscopic common bile duct exploration are not mandatory. Published by Elsevier Inc.
Resumo:
Nowadays, competitiveness introduces new behaviors and leads companies to a discomforting situation and often to non adaptation to environmental requirements. A growing number of challenges associated with control of information in organizations with engineering activities can be seen, particularly, the growing amount of information subject to continuous changes. The innovative performance of an organization is directly proportional to its ability to manage information. Thus, the importance of information management is recognized by the search for more competent ways to face current demands. The purpose of this article was to analyze informationdependent processes in technology-based companies, through the four major stages of information management. The comparative method of cases and qualitative research were used. The research was conducted in nine technology-based companies which were incubated or recently went through the incubating process at the Technological Park of Sao Carlos, in the state of Sao Paulo. Among the main results, it was found that in graduated companies information management and its procedures were identified as more conscious and structured in contrast to those of the incubated companies.
Resumo:
The novel coumarin-based 'turn-on' fluorescent probe (E)-3-(2,5-dimethoxybenzylideneamino)-7-hydroxy-2H-chromen-2-one (MGM) was designed, synthesized, and characterized. This compound shows high selectivity for Cu+2, combined with a large fluorescence enhancement upon binding to Cu2+. Benesi-Hildebrand and Job plots demonstrate that the stoichiometry of the Cu+2 complex formed is 2:1. Preliminary studies employing epifluorescence microscopy demonstrated that Cu+2 could be imaged in human neuroblastoma SH-SY5Y cells treated with MGM. (c) 2012 Elsevier Ltd. All rights reserved.
Resumo:
A new series of donor acceptor copolymers were synthesized via the Witting route and applied as an active layer in organic thin-films solar cells. These copolymers are composed of fluorene thiophene and phenylene thiophene units. The ratio between those was systematically varied, and copolymers containing 0%, 50%, and 75% of phenylene thiophene were characterized and evaluated when used in photovoltaic devices. The copolymers' composition, photophysical, electrical, and morphological properties are addressed and correlated with device performance. The 50% copolymer ratio was found to be the best copolymer of the series, yielding a power conversion efficiency (PCE) under air mass (AM) 1.5 conditions of 2.4% in the bilayer heterojunction with the C-60 molecule. Aiming at flexible electronics applications, solutions based on the heterojunction of this copolymer with PCBM (6,6-phenyl-C-61-butyric acid methyl ester) were also successfully deposited using an inkjet printing method and used as an active layer in solar cells.
Resumo:
The circumscription of genera belonging to tribe Bignonieae (Bignoniaceae) has traditionally been complex, with only a few genera having stable circumscriptions in the various classification systems proposed for the tribe. The genus Lundia, for instance, is well characterized by a series of morphological synapomorphies and its circumscription has remained quite stable throughout its history. Despite the stable circumscription of Lundia, the circumscription of species within the genus has remained problematic. This study aims to reconstruct the phylogeny of Lundia in order to refine species circumscriptions, gain a better understanding of relationships between taxa, and identify potential morphological synapomorphies for species and major clades. We sampled 26 accessions representing 13 species of Lundia, and 5 outgroups, and reconstructed the phylogeny of the genus using a chloroplast (ndhF) and a nuclear marker (PepC). Data derived from sequences of the individual loci were analyzed using parsimony and Bayesian inference, and the combined molecular dataset was analyzed with Bayesian methods. The monophyly of Lundia nitidula, a species with a particularly complex circumscription, was tested using Shimodaira-Hasegawa (SH) test and the approximately unbiased test for phylogenetic tree selection (AU test). In addition, 40 morphological characters were mapped onto the tree that resulted from the analysis of the combined molecular dataset in order to identify morphological synapomorphies of individual species and major clades. Lundia and most species currently recognized within the genus were strongly supported as monophyletic in all analyses. One species, Lundia nitidula, was not resolved as monophyletic, but the monophyly of this species was not rejected by the AU and SH tests. Lundia sect. Eriolundia is resolved as paraphyletic in all analyses, while Lundia sect. Eulundia is monophyletic and supported by the same morphological characters traditionally used to circumscribe this section. The phylogeny of Lundia contributed important information for a better circumscription of species and served as basis the taxonomic revision of the genus.
Resumo:
The use of nanoscale low-dimensional systems could boost the sensitivity of gas sensors. In this work we simulate a nanoscopic sensor based on carbon nanotubes with a large number of binding sites using ab initio density functional electronic structure calculations coupled to the Non-Equilibrium Green's Function formalism. We present a recipe where the adsorption process is studied followed by conductance calculations of a single defect system and of more realistic disordered system considering different coverages of molecules as one would expect experimentally. We found that the sensitivity of the disordered system is enhanced by a factor of 5 when compared to the single defect one. Finally, our results from the atomistic electronic transport are used as input to a simple model that connects them to experimental parameters such as temperature and partial gas pressure, providing a procedure for simulating a realistic nanoscopic gas sensor. Using this methodology we show that nitrogen-rich carbon nanotubes could work at room temperature with extremely high sensitivity. Copyright 2012 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License. [http://dx.doi.org/10.1063/1.4739280]
Resumo:
Nano-biocomposites based on a biodegradable bacterial copolyester, poly(hydroxybutyrate-co-hydroxyvalerate), have been elaborated with an organo-modified montmorillonite (OMMT) clay as nanofiller, and acetyl tributyl citrate as plasticizer. The corresponding (nano)structures, thermal and mechanical properties, permeability, and biodegradability have been determined. Polyhydroxyalkanoates are very thermal sensitive then to follow the degradation the corresponding matrices have been analyzed by size exclusion chromatography. The results indicate that the addition of the plasticizer decreases the thermo-mechanical degradation, during the extrusion. These nano-biocomposites show an intercalated/exfoliated structure with good mechanical and barrier properties, and an appropriated biodegradation kinetic. Intending to understand the changes in the thermal properties, the nano-biocomposites were characterized by thermal gravimetric analysis and differential scanning calorimetry. The presence of the OMMT clay did not influence significantly the transition temperatures. However, the filler not only acted as a nucleating agent which enhanced the crystallization, but also as a thermal barrier, improving the thermal stability of the biopolymer. The results indicated that the addition of the plasticizer reduces the glass transition temperature and the crystalline melting temperature. The plasticizer acts as a processing aid and increases the processing temperature range (lower melting temperature).
Resumo:
Introduction: The objective of this study was to investigate correlations between pulp oxygenation rates (%SpO(2)) and clinical diagnoses of reversible pulpitis (RP), irreversible pulpitis (IP), or pulp necrosis (PN). Methods: Sixty patients who presented with a tooth with endodontic pathology were grouped according to a clinical diagnosis of either RP (n = 20), IP (n = 20), or PN (n = 20). The clinical diagnosis was based on the patient's dental history, periapical radiographs, clinical inspection, and percussion and thermal sensitivity testing. Pulse oximetry (PO) was used to determine pulp oxygenation rates. For every patient, one additional endodontically treated tooth (negative control [NC], n = 60) and one additional healthy tooth with healthy pulp status (positive control [PC], n = 60) were evaluated. Analysis of variance, the Tukey HSD test, and the Student's t test were used for statistical analysis. Results: The mean % SpO(2) levels were as follows: RP: 87.4% (standard deviation [SD] +/- 2.46), IP: 83.1% (SD +/- 2.29), PN: 74.6% (SD +/- 1.96), PC: 92.2% (SD +/- 1.84), and NC: 0% (SD +/- 0.0). There were statistically significant differences between RP, IP, and PM compared with NC and PC and between RP, IP, and PN (all P <= .01). Conclusions: The evaluation of pulp oxygenation rates by PO may be a useful tool to determine the different inflammatory stages of the pulp to aid in endodontic diagnosis. (JEndod 2012;38:880-883)
Resumo:
The President of Brazil established an Interministerial Work Group in order to “evaluate the model of classification and valuation of disabilities used in Brazil and to define the elaboration and adoption of a unique model for all the country”. Eight Ministries and/or Secretaries participated in the discussion over a period of 10 months, concluding that a proposed model should be based on the United Nations Convention on the Rights of Person with Disabilities, the International Classification of Functioning, Disability and Health, and the ‘support theory’, and organizing a list of recommendations and necessary actions for a Classification, Evaluation and Certification Network with national coverage.
Resumo:
The aim of the present study was to evaluate the efficacy of QMiX, SmearClear, and 17% EDTA for the debris and smear layer removal from the root canal and its effects on the push-out bond strength of an epoxy-based sealer by scanning electron microscopy (SEM). Forty extracted human canines (n = 10) were assigned to the following final rinse protocols: G1-distilled water (control), G2–17% EDTA, G3-SmearClear, and G4-QMiX. The specimens were submitted to a SEM analysis to evaluate the presence of debris and smear layer, respectively, in the apical or cervical segments. In sequence, forty extracted human maxillary canines with the root canals instrumented were divided into four groups (n = 10) similar to the SEM analysis study. After the filling with AH Plus, the roots were transversally sectioned to obtain dentinal slices. The specimens were submitted to a push-out bond strength test using an electromechanical testing machine. The statistical analysis for the SEM and push-out bond strength studies were performed using the Kruskal–Wallis and Dunn tests (α = 5%). There was no difference among the G2, G3, and G4 efficacy in removing the debris and smear layer (P > 0.05). The efficacy of these groups was superior to the control group. The push-out bond strength values of G2, G3, and G4 were superior to the control group. The ability to remove the debris and smear layer by SmearClear and QMiX was as effective as the 17% EDTA. The final rinse with these solutions promoted similar push-out bond strength values.