Instituto de Ciência e Tecnologia (ICT)

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Crystallisation of melt-spun Al-Fe-Nd-Cu alloys
(Trans Tech Publications Ltd, 2000-01-01) Espinosa, José Waldo Martínez; Cardoso, Kátia Regina [UNIFESP]; Yavari, Alain Reza; Botta, Walter Jose; Eckert, Jurgen; Schlorb, Heike; Schultz, Ludwig; Universidade Federal de São Paulo (UNIFESP); Inst Natl Polytech Grenoble
Many high-strength Al-based alloys have been developed recently after it was found that for certain composition range, crystallisation from amorphous alloys could lead to a composite structure consisting of primary nanocrystals embedded in an amorphous matrix. However, even better values of mechanical strength,vas reported for Al-bused fully crystallised alloys with a composite structure formed by a mixture of primary nanocrystals and quasicrystalline phases therefore, the development of new compositions continues to be of interest. In the present work we report on the crystallisation behaviour of amorphous melt-spun Al-Fc-Nd-Cu alloys. Crystallisation was studied by differential scanning calorimetry and the characterisation of samples partially and fully crystallised was performed by X-ray diffraction and transmission electron microscopy. For the alloy Al85Fe4Nd6Cu5 crystallisation occurred by multiple stage with the first peak being associated with primary Al and two DSC peaks observed at higher temperatures have been associated with metastable phases. These results are discussed in association with the effect of the Cu content ill the crystallisation behaviour as compared with Al-Fe-Nd alloys.
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Vasoplegic syndrome after off-pump coronary artery bypass surgery
(Elsevier B.V., 2003-02-01) Gomes, Walter José [UNIFESP]; Erlichman, Manes R. [UNIFESP]; Batista, Mario L.; Knobel, Marcos; Almeida, Dirceu Rodrigues de [UNIFESP]; Carvalho, Antonio Carlos [UNIFESP]; Catani, Roberto [UNIFESP]; Buffolo, Enio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Objective: the vasoplegic syndrome (VS) has been implicated in life-threatening complications after open heart surgery, where the whole-body inflammatory reaction is attributed to the cardiopulmonary bypass (CPB). Off-pump coronary artery bypass grafting (OPCAB) has been recently achieving growing enthusiasm mainly due avoiding the side effects of CPB. However herein the occurrence of VS in OPCAB is reported. Methods: the vasoplegic syndrome usual findings occurring in the early postoperative period include severe hypotension, tachycardia, normal or elevated cardiac output and low systemic vascular resistance. Four patients underwent to OPCAB presented all the signs of VS intraoperatively or within the first 6 postoperative h. Results: the patients needed aggressive vasoactive drug support for hemodynamic stabilization and all of them developed complications. These patients also had tendency to require administration of blood and blood derivatives due to diffuse and oozing type bleeding. Mean intensive care unit stay of surviving patients was 70 h and mean period of postoperative hospitalization was 9 days. Tumor necrosis factor-ot blood levels in one patient were elevated postoperatively though no signs of infection were observed. One patient died. Conclusions: Although vasoplegic syndrome can complicate OPCAB surgery, the rationale for avoiding CPB remains valid considering the benefits provided by OPCAB. (C) 2002 Elsevier Science B.V. All fights reserved.
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Nitrolinoleate activates PPAR gamma signaling in THP-1 cells: the importance of the p21Ras-MAP kinases signaling pathway
(Blackwell Publishing, 2006-06-01) Ferderbar, S.; Monteiro, Hugo Pequeno [UNIFESP]; Abdalla, Dulcineia Saes Parra [UNIFESP]; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
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A new strategy for direct measurement of sinus atrial conduction time by sinus node threshold determination in a rat-isolated atrium
(Iop Publishing Ltd, 2007-01-01) Magalhaes Galvao, Kleber de; Godoy, Carlos Marcelo Gurjao de [UNIFESP]; Univ Mogi Cruzes; Universidade Federal de São Paulo (UNIFESP)
In this work we have searched for experimental evidence that would corroborate the idea that nodal threshold (NT) is the minimum electric field strength able to promote direct sinus node reset that, in turn, can be verified by a decrease in corrected sinus node recovery time (CSNRT). We have performed direct measurements of sinus node conduction time (SACT) and estimation of atrium sinus conduction time (ASCT). Stimulating pulses (pulse and train methods) generated a uniform electric field, with strength ranging from 1.5-fold to 5-fold the atrial threshold (AT), in the center of the perfusion chamber where isolated right atria were placed. the AT and NT were 67.4 and 192.7 mV cm(-1), respectively. the CSNRT values, obtained with stimulation strength below or above NT, were, respectively (ms; mean +/- standard error of mean) 38.1 +/- 0.42 and 25.2 +/- 0.30. in addition, we verified that NT corresponds to approximately 3-fold the AT; SACT was 1.34-fold ASCT and the overdrive suppression decreases with the increment of stimulation pulse strength. Therefore, by using a new and accurate approach for SNRT determination, we have provided additional experimental evidence for the development of alternative sinus node evaluation methods.
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Digital television broadcasting in Brazil
(Ieee Computer Soc, 2008-04-01) Farias, Mylene Christine Queiroz de [UNIFESP]; Carvalho, Marcelo Menezes de [UNIFESP]; Alencar, Marcelo S.; Universidade Federal de São Paulo (UNIFESP)
Acesso aberto (Open Access)
A genetic symbiotic algorithm applied to the one-dimensional cutting stock problem
(Sociedade Brasileira de Pesquisa Operacional, 2009-08-01) Golfeto, Rodrigo Rabello; Moretti, Antonio Carlos; Salles Neto, Luiz Leduino de [UNIFESP]; Universidade Federal Fluminense Escola de Engenharia Industrial Metalúrgica; Universidade Estadual de Campinas (UNICAMP); Universidade Federal de São Paulo (UNIFESP)
This work presents a genetic symbiotic algorithm to minimize the number of objects and the setup in a one-dimensional cutting stock problem. The algorithm implemented can generate combinations of ordered lengths of stock (the cutting pattern) and, at the same time, the frequency of the cutting patterns, through a symbiotic process between two distinct populations, solutions and cutting patterns. Working with two objectives in the fitness function and with a symbiotic relationship between the two populations, we obtained positive results when compared with other methods described in the literature.
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Label Propagation Through Neuronal Synchrony
(Ieee, 2010-01-01) Quiles, Marcos Gonçalves [UNIFESP]; Zhao, Liang; Breve, Fabricio A.; Rocha, Anderson; Universidade Federal de São Paulo (UNIFESP)
Semi-Supervised Learning (SSL) is a machine learning research area aiming the development of techniques which are able to take advantage from both labeled and unlabeled samples. Additionally, most of the times where SSL techniques can be deployed, only a small portion of samples in the data set is labeled. To deal with such situations in a straightforward fashion, in this paper we introduce a semi-supervised learning approach based on neuronal synchrony in a network of coupled integrate-and-fire neurons. For that, we represent the input data set as a graph and model each of its nodes by an integrate-and-fire neuron. Thereafter, we propagate the class labels from the seed samples to unlabeled samples through the graph by means of the emerging synchronization dynamics. Experimentations on synthetic and real data show that the introduced technique achieves good classification results regardless the feature space distribution or geometrical shape.
Acesso aberto (Open Access)
O problema de corte de estoque unidimensional multiperíodo
(Sociedade Brasileira de Pesquisa Operacional, 2010-04-01) Poldi, Kelly Cristina [UNIFESP]; Arenales, Marcos Nereu; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
The Multiperiod Cutting Stock Problem arises embedded in the production planning and programming in many industries which have a cutting process as an important stage. Ordered items have different due date over a finite planning horizon. A large scale integer linear optimization model is proposed. The model makes possible to anticipate or not the production of items. Unused objects in inventory in a period become available to the next period, added to new inventory, which are acquired or produced by the own company. The mathematical model's objective considers the waste in the cutting process, and costs for holding objects and final items. The simplex method with column generation was specialized to solve the linear relaxation. Some preliminary computational experiments showed that the multiperiod model could obtain effective gains when compared with the lot-for-lot solution, which is typically used in practice. However, in real world problems, the fractional solution is useless. So, additionally, two rounding procedures are developed to determine integer solutions for multiperiod cutting stock problems. Such procedures are based on a rolling horizon scheme, which roughly means, find an integer solution only for the first period, since this is the solution to be, in fact, carried out. Finally, we conclude that the proposed model for multiperiod cutting stock problems allows flexibility on analyzing a solution to be put in practice. The multiperiod cutting problem can be a tool that provides the decision maker a wide view of the problem and it may help him/her on making decisions.
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Visualization and simulation of 3D artificial neural structures generated by L-system
(Springer, 2010-06-01) Coelho, Regina Celia [UNIFESP]; Calonego, Nivaldi; Consularo, Luis Augusto; Universidade Federal de São Paulo (UNIFESP); UNEMAT Univ Estado Mato Grosso; TSE Tribunal Super Eleitoral STI CLOGI SEAD
This paper presents the visualization and simulation environment of 3D artificial neural structures. A stochastic L-system has been employed to generate neural structures based on features extracted from natural cells and it takes into account an hierarchical description of each neurite to allow interactions of the users in the virtual environment built. the implemented distributed virtual reality environment has its architecture explained, as well as its user interaction features to handle virtual neural structures. Furthermore, attraction/repulsion trophic fields had their effects simulated into these virtual neural structures. This approach illustrates aspects related to the neurogenesis and neural reorganization processes regarding attractive, repulsive or both interaction fields.
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Low-Level Laser Therapy Associated to N-Acetylcysteine Lowers Macrophage Inflammatory Protein-2 (MIP-2) mRNA Expression and Generation of Intracellular Reactive Oxygen Species in Alveolar Macrophages
(Mary Ann Liebert Inc, 2010-12-01) Mafra de Lima, Flavia; Villaverde, Antonio Balbin; Albertini, Regiane; Ligeiro de Oliveira, Ana Paula; Castro-Faria-Neto, Hugo Caire; Aimbire, Flavio [UNIFESP]; UNIVAP; Univ Camilo Castelo Branco UNICASTELO; Ctr Univ Nove de Julho UNINOVE; Inst Biomed Sci; IOC; Universidade Federal de São Paulo (UNIFESP)
Objective: the aim of this work was to investigate the low-level laser therapy (LLLT) effect on alveolar macrophages (AM) activated by oxidative stress and lipopolysaccharide (LPS). Background data: LLLT has been reported to actuate positively relieving the late and early symptoms of airway and lung inflammation. It is not known if the increased MIP-2mRNA expression and intracellular reactive oxygen species (ROS) generation observed in acute lung inflammation (ALI) can be influenced by LLLT. Materials and Methods: Rat AM cell line (AMJ2-C11) was cultured with LPS or H(2)O(2) and laser irradiated. MIP-2mRNA and ROS production in the AM were evaluated by Real Time-PCR and the 2',7'-dichlorofluorescin diacetate (DCFH-DA) respectively. the NF-kappa B protein in the AM was measured by the enzyme linked immunoassay method. To investigate the antioxidant effect of laser, the AM were prebathed with N-acetylcysteine (NAC) and then irradiated with laser. LLLT was also studied in the presence of an inhibitor of NF-kappa B (BMS 205820). in addition, the effect of LLLT on NF-kappa B protein was investigated. Results: LLLT attenuated the MIP-2mRNA expression and intracellular ROS generation after LPS or H(2)O(2). When the AM were pretreated with NAC, the laser effect was potentiated. BMS 205820 suppresses the effect of LLLT on MIP-2mRNA expression and ROS generation, stimulated by LPS or H(2)O(2). On NF-kappa B transcription factor, both the LLLT and NAC reduced this protein in the AM exposed to LPS or H(2)O(2). the synergistic effect between LLLT and NAC on the reduction the NF-kappa B was also evidenced. Conclusion: Results indicate that there is a synergistic action of LLLT with NAC on MIP-2mRNA expression from LPS-or H(2)O(2)-stimulated AM, and that both ROS intracellular generation and NF-kB signaling seem to be involved.
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Magnetoelectric Contribution to Magnetoelastic Coupling in Pb(Fe1/2Nb1/2)O-3 Multiferroics Ceramics
(Taylor & Francis Ltd, 2011-01-01) Fraygola, B.; Frizon, N.; Lente, M. H. [UNIFESP]; Coelho, Adelino A.; Garcia, D.; Eiras, J. A.; Universidade Federal de São Carlos (UFSCar); Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)
In this work, electrical permittivity, magnetic and anelastic measurements in lead iron niobate ceramics (PFN) were performed in the frequency and temperature range from 1 kHz to 10 MHz and from 15 K to 400 K, respectively. Anelastic results characterized unambiguously the magnetoelectric effect in the PFN, demonstrating that ME coupling arises indirectly via strain contribution rather than a direct coupling between electrical and magnetic order parameters.
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AUTOMATIC SUBCORTICAL TISSUE SEGMENTATION OF MR IMAGES USING OPTIMUM-PATH FOREST CLUSTERING
(Ieee, 2011-01-01) Cappabianco, Fabio Augusto Menocci [UNIFESP]; Ide, Jaime Shinsuke [UNIFESP]; Falcao, Alexandre; Li, Chiang-shan R.; Universidade Federal de São Paulo (UNIFESP)
Automatic MR-image segmentation of brain tissues is an important issue in neuroimaging. For instance, it is a key methodological component of a popular technique denominated voxel-based morphometry (VBM), which quantifies gray-matter (GM) volumes from MR images. However, segmentation accuracy in some subcortical regions on the basis of extant methods is not satisfactory, compromising VBM results. We combine a probabilistic atlas and a fast clustering approach based on optimum connectivity between voxels in their feature space. The algorithm exploits local image properties and global information from the atlas as features to group GM and white-matter (WM) voxels in distinct clusters, and uses the total probability values inside the clusters to label them as GM or WM. This new method is validated in the region of the thalamus and outperformed two widely used methods packaged in SPM and FSL.
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Influence of Domain Switching and Domain Wall Bending on the Electrical Permittivity of PZT Thin Films
(Taylor & Francis Ltd, 2011-01-01) Lente, Manuel Henrique [UNIFESP]; Bacichetti, Antonio Leondino; Mendes, Renata Gonçalves; Eiras, Jose Antonio; Universidade Federal de São Paulo (UNIFESP); Universidade Federal de São Carlos (UFSCar)
The electrical permittivity dependence on the electric bias field was investigated in Pb(Zr-0.53, Ti-0.47)O-3 films. the results revealed the existence of two mechanisms contributing to the permittivity. the first one was related to the domain switching, which was responsible for a strong nonlinear dielectric response. the second mechanism was associated with the non-180 degrees domain wall vibrations, which presented a reasonable linear electrical behavior with the applied field, contributing always to the permittivity independently of the poling state of the sample. the reduction of the electrical permittivity with increasing the bias field was related to the bending of non-180 degrees domain walls.
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Selecting salient objects in real scenes: An oscillatory correlation model
(Elsevier B.V., 2011-01-01) Quiles, Marcos G. [UNIFESP]; Wang, DeLiang; Zhao, Liang; Romero, Roseli A. F.; Huang, De-Shuang; Ohio State Univ; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Chinese Acad Sci
Attention is a critical mechanism for visual scene analysis. By means of attention, it is possible to break down the analysis of a complex scene to the analysis of its parts through a selection process. Empirical studies demonstrate that attentional selection is conducted on visual objects as a whole. We present a neurocomputational model of object-based selection in the framework of oscillatory correlation. By segmenting an input scene and integrating the segments with their conspicuity obtained from a saliency map, the model selects salient objects rather than salient locations. the proposed system is composed of three modules: a saliency map providing saliency values of image locations, image segmentation for breaking the input scene into a set of objects, and object selection which allows one of the objects of the scene to be selected at a time. This object selection system has been applied to real gray-level and color images and the simulation results show the effectiveness of the system. (C) 2010 Elsevier B.V. All rights reserved.
Acesso aberto (Open Access)
Porous stainless steel for biomedical applications
(ABM, ABC, ABPol, 2011-01-01) Mariotto, Sabrina de Fátima Ferreira; Guido, Vanessa; Yao Cho, Liu; Soares, Cristina Pacheco; Cardoso, Kátia Regina [UNIFESP]; Universidade do Vale do Paraíba Instituto de Pesquisa e Desenvolvimento; Universidade Federal de São Paulo (UNIFESP)
Porous 316L austenitic stainless steel was synthesized by powder metallurgy with relative density of 0.50 and 0.30 using 15 and 30 wt. (%) respectively of ammonium carbonate and ammonium bicarbonate as foaming agents. The powders were mixed in a planetary ball mill at 60 rpm for 10 minutes. The samples were uniaxially pressed at 287 MPa and subsequently vacuum heat treated in two stages, the first one at 200 ºC for 5 hours to decompose the carbonate and the second one at 1150 ºC for 2 hours to sinter the steel. The sintered samples had a close porous structure and a multimodal pore size distribution that varied with the foaming agent and its concentration. The samples obtained by addition of 30 wt. (%) of foaming agents had a more homogeneous porous structure than that obtained with 15 wt. (%). The MTT cytotoxicity test (3-[4,5-dimethylthiazol]-2,5-diphenyltetrazolium bromide) was used to evaluate the mitochondrial activity of L929 cells with samples for periods of 24, 48, and 72 hours. The cytotoxicity test showed that the steel foams were not toxic to fibroblast culture. The sample with the best cellular growth, therefore the most suitable for biomedical applications among those studied in this work, was produced with 30 wt. (%) ammonium carbonate. In this sample, cell development was observed after 48 hours of incubation, and there was adhesion and spreading on the material after 72 hours. Electrochemical experiments using a chloride-containing medium were performed on steel foams and compared to massive steel. The massive steel had a better corrosion performance than the foams as the porosity contributes to increase the surface area exposed to the corrosive medium.
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Evolutionary model trees for handling continuous classes in machine learning
(Elsevier B.V., 2011-03-01) Barros, Rodrigo C.; Ruiz, Duncan D.; Basgalupp, Marcio P. [UNIFESP]; Universidade de São Paulo (USP); Pontificia Univ Catolica Rio Grande do Sul; Universidade Federal de São Paulo (UNIFESP)
Model trees are a particular case of decision trees employed to solve regression problems. They have the advantage of presenting an interpretable output, helping the end-user to get more confidence in the prediction and providing the basis for the end-user to have new insight about the data, confirming or rejecting hypotheses previously formed. Moreover, model trees present an acceptable level of predictive performance in comparison to most techniques used for solving regression problems. Since generating the optimal model tree is an NP-Complete problem, traditional model tree induction algorithms make use of a greedy top-down divide-and-conquer strategy, which may not converge to the global optimal solution. in this paper, we propose a novel algorithm based on the use of the evolutionary algorithms paradigm as an alternate heuristic to generate model trees in order to improve the convergence to globally near-optimal solutions. We call our new approach evolutionary model tree induction (E-Motion). We test its predictive performance using public UCI data sets, and we compare the results to traditional greedy regression/model trees induction algorithms, as well as to other evolutionary approaches. Results show that our method presents a good trade-off between predictive performance and model comprehensibility, which may be crucial in many machine learning applications. (C) 2010 Elsevier Inc. All rights reserved.
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Low-level laser therapy (LLLT) acts as cAMP-elevating agent in acute respiratory distress syndrome
(Springer, 2011-05-01) Lima, Flavia Mafra de; Moreira, Leonardo M.; Villaverde, A. B.; Albertini, Regiane; Castro-Faria-Neto, Hugo C.; Aimbire, Flavio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Res & Dev Inst IP&D; Dept Biosyst Engn; Unicastelo; Ctr Univ Nove Julho Uninove; Fiocruz MS
The aim of this work was to investigate if the low-level laser therapy (LLLT) on acute lung inflammation (ALI) induced by lipopolysaccharide (LPS) is linked to tumor necrosis factor (TNF) in alveolar macrophages (AM) from bronchoalveolar lavage fluid (BALF) of mice. LLLT has been reported to actuate positively for relieving the late and early symptoms of airway and lung inflammation. It is not known if the increased TNF mRNA expression and dysfunction of cAMP generation observed in ALI can be influenced by LLLT. for in vivo studies, Balb/c mice (n = 5 for group) received LPS inhalation or TNF intra nasal instillation and 3 h after LPS or TNF-alpha, leukocytes in BALF were analyzed. LLLT administered perpendicularly to a point in the middle of the dissected bronchi with a wavelength of 660 nm and a dose of 4.5 J/cm(2). the mice were irradiated 15 min after ALI induction. in vitro AM from mice were cultured for analyses of TNF mRNA expression and protein and adenosine3':5'-cyclic monophosphate (cAMP) levels. One hour after LPS, the TNF and cAMP levels in AM were measured by ELISA. RT-PCR was used to measure TNF mRNA in AM. the LLLT was inefficient in potentiating the rolipram effect in presence of a TNF synthesis inhibitor. LLLT attenuated the neutrophil influx and TNF in BALF. in AM, the laser increased the cAMP and reduced the TNF-alpha mRNA. LLLT increases indirectly the cAMP in AM by a TNF-dependent mechanism.
Acesso aberto (Open Access)
Assessing the solvation mechanism of C-60(OH)(24) in aqueous solution
(Elsevier B.V., 2011-05-09) Maciel, Cleiton; Fileti, Eudes Eterno [UNIFESP]; Rivelino, Roberto; Universidade Federal de São Paulo (UNIFESP); Universidade Federal do ABC (UFABC); Universidade Federal da Bahia (UFBA)
Using molecular dynamics simulations, combined with the thermodynamic integration algorithm, we examine the hydration mechanism of C-60(OH)(24) under ambient conditions. We analyze its structural features, dynamics, and hydration free energy. Our results have been compared with a pristine fullerene aqueous system. Despite the number of hydroxyl groups in the fullerenol, its hydration entropy is rather similar to that calculated for C-60. On the other hand, we have calculated a dramatically negative free energy of about -354 kJ/mol for the fullerenol, whereas pure fullerene presents a positive value of about 59 kJ/mol. On this basis, our study indicates that the hydration of C-60(OH)(24) is guided by an enthalpy-driven process. (C) 2011 Elsevier B.V. All rights reserved.
Acesso aberto (Open Access)
Biochemical characterization of a protein tyrosine phosphatase from Trypanosoma cruzi involved in metacyclogenesis and cell invasion
(Elsevier B.V., 2011-05-13) Gallo, Gloria [UNIFESP]; Ramos, Thiago Cesar Prata [UNIFESP]; Tavares, Fernanda; Rocha, Antonio Augusto [UNIFESP]; Machi, Emerson; Schenkman, Sergio [UNIFESP]; Bahia, Diana [UNIFESP]; Pesquero, João Bosco [UNIFESP]; Wuertele, Martin [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Ctr Biol Mol Estrutural
Protein tyrosine phosphatases (PTPs) form a large family of enzymes involved in the regulation of numerous cellular functions in eukaryotes. Several protein tyrosine phosphatases have been recently identified in trypanosomatides. Here we report the purification and biochemical characterization of TcPTP1, a protein tyrosine phosphatase from Trypanosoma cruzi, the causing agent of Chagas' disease. the enzyme was cloned and expressed recombinantly in Escherichia coli and purified by Ni-affinity chromatography. Biochemical characterization of recombinant TcPTP1 with the PTP pseudo-substrate pNPP allowed the estimation of a Michaelis-Menten constant K-m of 4.5 mM and a k(cat) of 2.8 s(-1). We were able to demonstrate inhibition of the enzyme by the PTP1b inhibitor BZ3, which on its turn was able to accelerate the differentiation of epimastigotes into metacyclic forms of T. cruzi induced by nutritional stress. Additionally, this compound was able to inhibit by 50% the infectivity of T. cruzi trypomastigotes in a separate cellular assay. in conclusion our results indicate that TcPTP1 is of importance for cellular differentiation and invasivity of this parasite and thus is a valid target for the rational drug design of potential antibiotics directed against T. cruzi. (C) 2011 Elsevier Inc. All rights reserved.
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A minireview of cellulose nanocrystals and its potential integration as co-product in bioethanol production
(Soc Chilena Quimica, 2011-06-01) Duran, Nelson; Lemes, Ana Paula [UNIFESP]; Duran, Marcela; Freer, Juanita; Baeza, Jaime; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Univ Nacl Estadual Sao Paulo
Cellulose nanocrystals appeared as important bio-based products and the collected information in term of production, characterization and application suggest that this nanomaterial could be easily extrapolated to bioethanol production. This review describes recent published syntheses using chemical and enzymatic hydrolyses and different preparations such as high pressure homogenization. Their industrial and medical applications, such as controled of delivery carriers, suggest a large projection of this nanomaterial. The most important aspect in this collected data is the potential to decrease significantly the final cost of the enzymes or the hydrolysis pre-treatment of lignocellulosic materials of all bioethanol processes in such a way that it could be economically feasible from materials such as bagasse, straw or wood resources.

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