Wing symmetry and flight activity

We compared bilateral structures (wings) of flying versus non-flying insects in two lines of #P. megistus$ which differed only by their laboratory maintenance time : PM1 (more than five generations in insectarium) and PM2 (one or two generations under laboratory conditions). Insects were processed according to Schofield (1980) and observed through a period of 30 days. During this time the insects that had flight (gf, for "good" flyers) and their wings extracted for morphometry. At the end of this period the same number of insects that did not fly (bf, for "bad" flyers), were used as a control and submitted to the same analysis. Fluctuating asymmetry (FA) was estimated at nine distances (A, B, C, D, E, H, 1, 2 and 3). FA occurs as a result of random deviations in the developement of bilaterally symmetric traits, and is considered as a useful trait for monitoring stress in the laboratory and in natural environments (Parsons, 1990). For each sample, FA values were calculated for each character as the sum of the squared signed differences between sides divided by the number of individuals sampled, i.e., ((Li-Ri)2)/N). This is equivalent to index 5 of Palmer and Strobek (1986) which they state is best able to discriminate true differences in FA. As the index to estimate asymmetry is a variance, differences between samples were tested for significance using tests of homogeneity of variances (Ho : s1=s2). Due to low sample size, statistical analysis was not applied to PM2 females (only two individuals). The PM1 bf females (6 insects) were more asymmetric than their gf counterparts (5 insects) at four wings traits (2,3 in PM1 and 2 in PM2) (gf=7 insects and bf=7 insects). Conversely, one character out of nine was found more asymmetric in gf either from PM1 (character 3 for PM1 females and E for PM1 males) or PM2 males (character D). (Résumé d'auteur

Permeability, Roughness And Topography Of Enamel After Bleaching: Tracking Channels Of Penetration With Silver Nitrate

Aim: This study evaluated the surface roughness, topography and permeability of bovine enamel by profilometry and scanning electron microscopy (SEM) with and without silver nitrate solution, after exposure to different bleaching agents. Methods: Fifty-two enamel samples were randomly divided into four groups (n=13): CP16% -16% carbamide peroxide - Whiteness Perfect; HP6% - 6% hydrogen peroxide - White Class; HP35% - 35% hydrogen peroxide Whiteness HP Maxx; and Control - not bleached and kept in artificial saliva. For roughness analysis, average surface roughness (Ra) and flatness coefficient (Rku) parameters were used. The topography and permeability were examined by SEM. For permeability evaluation, the samples were immersed in a 50% silver nitrate solution and analyzed using a backscattered electron and secondary electron mode. Results: For the roughness (Ra) evaluation, Kruskal-Wallis and Wilcoxon Signed Ranks Test were used, showing an increase on the surface roughness in all bleached groups. The Rku parameter suggested changes on enamel integrity. The SEM micrographs indicated changes on enamel topography and different levels of silver nitrate penetration in the samples of the bleached groups. In the overall analysis, the bleaching agents promoted surface changes and higher silver nitrate penetration when compared to the control group. Conclusions: It may be concluded that different bleaching agents might alter the topography and roughness of enamel surface. Moreover, the higher infiltration of silver nitrate suggests an easier penetration path for the oxygen molecules into the dentin substrate.10116Nathoo, S.A., The chemistry and mechanisms of extrinsic and intrinsic discoloration (1997) J Am Dent Assoc, 128 (SUPPL.), pp. 6S-10SMcEvoy, S.A., Chemical agents for removing intrinsic stains from vital teeth. II. Current techniques and their clinical application (1989) Quintessence Int, 20, pp. 379-384Ben-Amar, A., Liberman, R., Gorfil, C., Bernstein, Y., Effect of mouthguard bleaching on enamel surface (1995) Am J Dent, 8, pp. 29-32Lynch, E., Sheerin, A., Samarawickrama, D.Y., Atherton, M.A., Claxson, A.W., Hawkes, J., Molecular mechanisms of the bleaching actions associated with commercially-available whitening oral health care products (1995) J Ir Dent Assoc, 41, pp. 94-102Bowles, W.H., Ugwuneri, Z., Pulp chamber penetration by hydrogen peroxide following vital bleaching procedures (1987) J Endod, 13, pp. 375-377Sun, G., The role of lasers in cosmetic dentistry (2000) Dent Clin North Am, 44, pp. 831-850Hegedus, C., Bistey, T., Flora-Nagy, E., Keszthelyi, G., Jenei, A., An atomic force microscopy study on the effect of bleaching agents on enamel surface (1999) J Dent, 27, pp. 509-515Park, H.J., Kwon, T.Y., Nam, S.H., Kim, H.J., Kim, K.H., Kim, Y.J., Changes in bovine enamel after treatment with a 30% hydrogen peroxide bleaching agent (2004) Dent Mater J, 23, pp. 517-521Iwamoto, N., Shimada, Y., Tagami, J., Penetration of silver nitrate into bleached enamel, dentin, and cementum (2007) Quintessence Int, 38, pp. e183-e188Cavalli, V., Arrais, C.A., Giannini, M., Ambrosano, G.M., High-concentrated carbamide peroxide bleaching agents effects on enamel surface (2004) J Oral Rehabil, 31, pp. 155-159Hosoya, N., Honda, K., Iino, F., Arai, T., Changes in enamel surface roughness and adhesion of Streptococcus mutans to enamel after vital bleaching (2003) J Dent, 31, pp. 543-548Josey, A.L., Meyers, I.A., Romaniuk, K., Symons, A.L., The effect of a vital bleaching technique on enamel surface morphology and the bonding of composite resin to enamel (1996) J Oral Rehabil, 23, pp. 244-250Lee, C.Q., Cobb, C.M., Zargartalebi, F., Hu, N., Effect of bleaching on microhardness, morphology, and color of enamel (1995) Gen Dent, 43, pp. 158-160McGuckin, R.S., Babin, J.F., Meyer, B.J., Alterations in human enamel surface morphology following vital bleaching (1992) J Prosthet Dent, 68, pp. 754-760Pinto, C.F., Oliveira, R., Cavalli, V., Giannini, M., Peroxide bleaching agent effects on enamel surface microhardness, roughness and morphology (2004) Braz Oral Res, 18, pp. 306-311Shannon, H., Spencer, P., Gross, K., Tira, D., Characterization of enamel exposed to 10% carbamide peroxide bleaching agents (1993) Quintessence Int, 24, pp. 39-44Zalkind, M., Arwaz, J.R., Goldman, A., Rotstein, I., Surface morphology changes in human enamel, dentin and cementum following bleaching: a scanning electron microscopy study (1996) Endod Dent Traumatol, 12, pp. 82-88Ernst, C.P., Marroquin, B.B., Willershausen-Zonnchen, B., Effects of hydrogen peroxide-containing bleaching agents on the morphology of human enamel (1996) Quintessence Int, 27, pp. 53-56Gultz, J., Kaim, J., Scherer, W., Gupta, H., Two in-office bleaching systems: a scanning electron microscope study (1999) Compend Contin Educ Dent, 20, pp. 965-968. , 70quiz 72Haywood, V.B., Heymann, H.O., Nightguard vital bleaching: how safe is it? (1991) Quintessence Int, 22, pp. 515-523Haywood, V.B., Leech, T., Heymann, H.O., Crumpler, D., Bruggers, K., Nightguard vital bleaching: effects on enamel surface texture and diffusion (1990) Quintessence Int, 21, pp. 801-804Oltu, U., Gurgan, S., Effects of three concentrations of carbamide peroxide on the structure of enamel (2000) J Oral Rehabil, 27, pp. 332-340Spalding, M., Taveira, L.A., de Assis, G.F., Scanning electron microscopy study of dental enamel surface exposed to 35% hydrogen peroxide: alone, with saliva, and with 10% carbamide peroxide (2003) J Esthet Restor Dent, 15, pp. 154-165Sulieman, M., Addy, M., Macdonald, E., Rees, J.S., A safety study in vitro for the effects of an in-office bleaching system on the integrity of enamel and dentine (2004) J Dent, 32, pp. 581-590Tong, L.S., Pang, M.K., Mok, N.Y., King, N.M., Wei, S.H., The effects of etching, micro-abrasion, and bleaching on surface enamel (1993) J Dent Res, 72, pp. 67-71Bagheri, R., Tyas, M.J., Burrow, M.F., Subsurface degradation of resin-based composites (2007) Dent Mater, 23, pp. 944-951Reis, A., Grande, R.H., Oliveira, G.M., Lopes, G.C., Loguercio, A.D., A 2-year evaluation of moisture on microtensile bond strength and nanoleakage (2007) Dent Mater, 23, pp. 862-870Ritter, A.V., Ghaname, E., Leonard, R.H., The influence of dental unit waterline cleaners on composite-to-dentin bond strengths (2007) J Am Dent Assoc, 138, pp. 985-991. , quiz 1022-3Sano, H., Shono, T., Takatsu, T., Hosoda, H., Microporous dentin zone beneath resin-impregnated layer (1994) Oper Dent, 19, pp. 59-64Nanci, A., (2007) Ten Cate's oral histology: development, structure, and function, , 7th ed. Saint Louis: Mosby-ElsevierCeliberti, P., Pazera, P., Lussi, A., The impact of ozone treatment on enamel physical properties (2006) Am J Dent, 19, pp. 67-72Chen, J.H., Xu, J.W., Shing, C.X., Decomposition rate of hydrogen peroxide bleaching agents under various chemical and physical conditions (1993) J Prosthet Dent, 69, pp. 46-48Reyto, R., Laser tooth whitening (1998) Dent Clin North Am., 42, pp. 755-762. , xiBitter, N.C., Sanders, J.L., The effects of four bleaching agents on the enamel surface: a scanning electron microscopic study (1993) Quintessence Int, 24, pp. 817-824Leonard Jr., R.H., Austin, S.M., Haywood, V.B., Bentley, C.D., Change in pH of plaque and 10% carbamide peroxide solution during nightguard vital bleaching treatment (1994) Quintessence Int, 25, pp. 819-823Leonard Jr., R.H., Bentley, C.D., Haywood, V.B., Salivary pH changes during 10% carbamide peroxide bleaching (1994) Quintessence Int, 25, pp. 547-550Li, Y., Biological properties of peroxide-containing tooth whiteners (1996) Food Chem Toxicol, 34, pp. 887-904Price, R.B., Sedarous, M., Hiltz, G.S., The pH of tooth-whitening products (2000) J Can Dent Assoc, 66, pp. 421-426Yeh, S.T., Su, Y., Lu, Y.C., Lee, S.Y., Surface changes and acid dissolution of enamel after carbamide peroxide bleach treatment (2005) Oper Dent, 30, pp. 507-515Justino, L.M., Tames, D.R., Demarco, F.F., In situ and in vitro effects of bleaching with carbamide peroxide on human enamel (2004) Oper Dent, 29, pp. 219-22

Effect Of Post Type And Restorative Techniques On The Strain And Fracture Resistance Of Flared Incisor Roots

Restoring flared endodontically treated teeth continues to be a challenge for clinicians. This study evaluated the effect of post types and restorative techniques on the strain, fracture resistance, and fracture mode of incisors with weakened roots. One hundred five endodontically treated bovine incisors roots (15 mm) were divided into 7 groups (n=15). The two control groups were (C) intact roots restored with Cpc (cast posts and core) or Gfp (glass fiber posts). The five experimental groups were (F) flared roots restored with GfpAp (Gfp associated with accessory glass fiber posts), GfpRc (anatomic Gfp, relined with composite resin), and GfpRcAp (anatomized Gfp with resin and accessory glass fiber posts). All teeth were restored with metal crowns. Mechanical fatigue was performed with 3x10 5/50 N. Specimens were loaded at 45°, and the strain values (μS) were obtained on root buccal and proximal surfaces. Following that, the fracture resistance (N) was measured. One-way ANOVA and Tukey's HSD tests (α=0.05) were applied, and failure mode was checked. No significant difference in strain values among the groups was found. Cpc presented lower fracture resistance and more catastrophic failures in flared roots. Gfp associated with composite resin or accessory glass fiber posts seems to be an effective method to improve the biomechanical behavior of flared roots.223230237Coelho, C.S., Biffi, J.C., Silva, G.R., Abrahão, A., Campos, R.E., Soares, C.J., Finite element analysis of weakened roots restored with composite resin and posts (2009) Dent Mater J, 28, pp. 671-678Teixeira, C.S., Silva-Sousa, Y.T., Sousa-Neto, M.D., Bond strength of fiber posts to weakened roots after resin restoration with different light-curing times (2009) J Endod, 35, pp. 1034-1039Zogheib, L.V., Pereira, J.R., do Valle, A.L., de Oliveira, J.A., Pegoraro, L.F., Fracture resistance of weakened roots restored with composite resin and glass fiber post (2008) Braz Dent J, 19, pp. 329-333Marchi, G.M., Mitsui, F.H., Cavalcanti, A.N., Effect of remaining dentine structure and thermal-mechanical aging on the fracture resistance of bovine roots with different post and core systems (2008) Int Endod J, 41, pp. 969-976da Silveira, T.C., Santos, F.M.C., Silva-Sousa, Y.T., de Sousa-Neto, M.D., Interfacial evaluation of experimentally weakened roots restored with adhesive materials and fibre posts: An SEM analysis (2008) J Dent, 36, pp. 672-682Moosavi, H., Maleknejad, F., Kimyai, S., Fracture resistance of endodontically-treated teeth restored using three root- reinforcement methods (2008) J Contemp Dent Pract, 9, pp. 30-37Bonfante, G., Kaizer, O.B., Pegoraro, L.F., do Valle, A.L., Fracture strength of teeth with flared root canals restored with glass fibre posts (2007) Int Dent J, 57, pp. 153-160Santos, A.F., Meira, J.B., Tanaka, C.B., Xavier, T.A., Ballester, R.Y., Lima, R.G., Can fiber posts increase root stresses and reduce fracture? (2010) J Dent Res, 89, pp. 587-591da Silva, N.R., Raposo, L.H., Versluis, A., Fernandes-Neto, A.J., Soares, C.J., The effect of post, core, crown type, and ferrule presence on the biomechanical behavior of endodontically treated bovine anterior teeth (2010) J Prosthet Dent, 104, pp. 306-317Silva, N.R., Castro, C.G., Santos-Filho, P.C., Silva, G.R., Campos, R.E., Soares, P.V., Influence of different post design and composition on stress distribution in maxillary central incisor: Finite element analysis (2009) Indian J Dent Res, 20, pp. 153-158Santos-Filho, P.C., Castro, C.G., Silva, G.R., Campos, R.E., Soares, C.J., Effects of post system and length on the strain and fracture resistance of root filled bovine teeth (2008) Int Endod J, 41, pp. 493-501Soares, C.J., Castro, C.G., Santos, F.P.C., Soares, P.V., Magalhaes, D., Martins, L.R., Two-dimensional FEA of dowels of different compositions and external surface configurations (2009) J Prosthodont, 18, pp. 36-42Macedo, V.C., de Faria, S.A.L., Martins, L.R., Effect of cement type, relining procedure, and length of cementation on pull-out bond strength of fiber posts (2010) J Endod, 36, pp. 1543-1546Leitune, V.C., Collares, F.M., Werner, S.S.M., Influence of chlorhexidine application at longitudinal push-out bond strength of fiber posts (2010) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 110, pp. 77-81Novais, V.R., Quagliatto, P.S., Bona, A.D., Correr-Sobrinho, L., Soares, C.J., Flexural modulus, flexural strength, and stiffness of fiber-reinforced posts (2009) Indian J Dent Res, 20, pp. 277-281Marchi, G.M., Paulillo, L.A., Pimenta, L.A., de Lima, F.A., Effect of different filling materials in combination with intraradicular posts on the resistance to fracture of weakened roots (2003) J Oral Rehabil, 30, pp. 623-629Soares, C.J., Pizi, E.C., Fonseca, R.B., Martins, L.R., Influence of root embedment material and periodontal ligament simulation on fracture resistance tests (2005) Braz Oral Res, 19, pp. 11-16Huysmans, M.C., Peters, M.C., van der Varst, P.G., Plasschaert, A.J., Failure behaviour of fatigue-tested post and cores (1993) Int Endod J, 26, pp. 294-300Soares, P.V., Santos-Filho, P.C., Gomide, H.A., Araujo, C.A., Martins, L.R., Soares, C.J., Influence of restorative technique on the biomechanical behavior of endodontically treated maxillary premolars. Part II: Strain measurement and stress distribution (2008) J Prosthet Dent, 99, pp. 114-122Kishen, A., Kumar, G.V., Chen, N.N., Stress-strain response in human dentine: Rethinking fracture predilection in post-core restored teeth (2004) Dent Traumatol, 20, pp. 90-10

Flocculation onset in Saccharomyces cerevisiae: effect of ethanol, heat and osmotic stress

Aims: To examine the effect of different stress conditions on the onset of flocculation in an ale-brewing strain, Saccharomyces cerevisiae NCYC 1195. Methods and Results: Flocculation was evaluated using the method of Soares, E.V. and Vroman, A. [Journal of Applied Microbiology (2003) 95, 325]; plasma membrane integrity was accessed using propidium iodide and the staining of the yeast cell wall was performed using calcofluor white M2R. Cells in exponential phase of growth were subjected to different stress conditions. The addition of 1%, 3% and 5% (v/v) ethanol, 1% and 3% (v/v) isopropanol or a brief heat shock (52ºC, 5 min), did not induce an early flocculation phenotype when compared with control cells. The addition of 10% (v/v) ethanol, a continuous mild heat-stress (37ºC) or an osmotic stress (0.5 or 1 mol l-1 of NaCl) did not induce a flocculent phenotype. Conclusions: Flocculation seems not to be induced as a response to different chemical (ethanol and isopropanol) and physical (heat and osmotic) stress conditions. Conversely, osmotic and ethanol [10% (v/v)] stress, as well as a continuous mild heat shock (37ºC), have a negative impact on the phenotype expression of flocculation. Significance and Impact of the Study: The findings reported here contribute to the elucidation of the control of yeast flocculation. This information might be useful to the brewing industry, as the time when the onset of flocculation occurs can determine the fermentation performance and the beer quality, as well as in other biotechnological industries where flocculation can be used as a cell separation process.ERASMUS; ISEP (Portugal)

A feasibility cachaca type recognition using computer vision and pattern recognition

Brazilian rum (also known as cachaça) is the third most commonly consumed distilled alcoholic drink in the world, with approximately 2.5 billion liters produced each year. It is a traditional drink with refined features and a delicate aroma that is produced mainly in Brazil but consumed in many countries. It can be aged in various types of wood for 1-3 years, which adds aroma and a distinctive flavor with different characteristics that affect the price. A research challenge is to develop a cheap automatic recognition system that inspects the finished product for the wood type and the aging time of its production. Some classical methods use chemical analysis, but this approach requires relatively expensive laboratory equipment. By contrast, the system proposed in this paper captures image signals from samples and uses an intelligent classification technique to recognize the wood type and the aging time. The classification system uses an ensemble of classifiers obtained from different wavelet decompositions. Each classifier is obtained with different wavelet transform settings. We compared the proposed approach with classical methods based on chemical features. We analyzed 105 samples that had been aged for 3 years and we showed that the proposed solution could automatically recognize wood types and the aging time with an accuracy up to 100.00% and 85.71% respectively, and our method is also cheaper.info:eu-repo/semantics/publishedVersio

A universal vaccine candidate against Plasmodium vivax malaria confers protective immunity against the three PvCSP alleles

Malaria is a highly prevalent parasitic disease in regions with tropical and subtropical climates worldwide. Among the species of Plasmodium causing human malaria, P. vivax is the second most prevalent and the most geographically widespread species. A major target of a pre-erythrocytic vaccine is the P. vivax circumsporozoite protein (PvCSP). In previous studies, we fused two recombinant proteins representing three allelic variants of PvCSP (VK210, VK247 and P. vivax-like) to the mumps virus nucleocapsid protein to enhance immune responses against PvCSP. The objective of the present study was to evaluate the protective efficacy of these recombinants in mice challenged with transgenic P. berghei parasites expressing PvCSP allelic variants. Formulations containing Poly (I:C) or Montanide ISA720 as adjuvants elicited high and long-lasting IgG antibody titers specific to each PvCSP allelic variant. Immunized mice were challenged with two existing chimeric P. berghei parasite lines expressing PvCSP-VK210 and PvCSP-VK247. We also developed a novel chimeric line expressing the third allelic variant, PvCSP-P. vivax-like, as a new murine immunization-challenge model. Our formulations conferred partial protection (significant delay in the time to reach 1% parasitemia) against challenge with the three chimeric parasites. Our results provide insights into the development of a vaccine targeting multiple strains of P. vivax.Host-parasite interactio

The Role of Depressive Symptomatology in Peri- and Post-Menopause

Objectives: There is evidence that menopausal symptoms manifested at peri-menopause occur less fre- quently when compared to the symptoms experienced at post-menopause. The aim of this study was to investigate this and to test the hypothesis that depressive symptomatology mediates the relationship between menopausal stage and symptom frequency. Methods: This cross-sectional study included 213 women (M age = 52 years), of whom 125 were peri- and 88 post-menopausal. Measures comprised the Center for Epidemiologic Studies-Depression scale (CES-D) and the Women’s Health Questionnaire (WHQ) vasomotor symptoms and somatic symptoms subscales. Results: Multiple mediated regression analyses provided evidence that somatic symptoms and vasomotor symptoms were less frequent at post- compared to peri-menopause, and that these differences were mediated by depressive symptomatology. Multivariate effect sizes ranged from small to moderate, and univariate effect sizes were uniformly small with wide confidence intervals. Conclusions: The frequency of vasomotor and somatic symptoms appears to increase with depressed affect. The management of symptoms could include interventions of a psychotherapeutic nature, which may offset this effect, particularly in women for whom depressive symptoms are a feature of the climac- teric syndrome. The extent to which depression and the climacteric syndrome may be causally related to one another remains unclear and longitudinal research should further examine the mechanisms of this association

Thoracic Electrical Impedance Tomography—The 2022 Veterinary Consensus Statement

Electrical impedance tomography (EIT) is a non-invasive real-time non-ionising imaging modality that has many applications. Since the first recorded use in 1978, the technology has become more widely used especially in human adult and neonatal critical care monitoring. Recently, there has been an increase in research on thoracic EIT in veterinary medicine. Real-time imaging of the thorax allows evaluation of ventilation distribution in anesthetised and conscious animals. As the technology becomes recognised in the veterinary community there is a need to standardize approaches to data collection, analysis, interpretation and nomenclature, ensuring comparison and repeatability between researchers and studies. A group of nineteen veterinarians and two biomedical engineers experienced in veterinary EIT were consulted and contributed to the preparation of this statement. The aim of this consensus is to provide an introduction to this imaging modality, to highlight clinical relevance and to include recommendations on how to effectively use thoracic EIT in veterinary species. Based on this, the consensus statement aims to address the need for a streamlined approach to veterinary thoracic EIT and includes: an introduction to the use of EIT in veterinary species, the technical background to creation of the functional images, a consensus from all contributing authors on the practical application and use of the technology, descriptions and interpretation of current available variables including appropriate statistical analysis, nomenclature recommended for consistency and future developments in thoracic EIT. The information provided in this consensus statement may benefit researchers and clinicians working within the field of veterinary thoracic EIT. We endeavor to inform future users of the benefits of this imaging modality and provide opportunities to further explore applications of this technology with regards to perfusion imaging and pathology diagnosis

Pharmacotherapy review: a proposal to improve medication adherence among hypertensive patients

Abstract Pharmacotherapy review is a structured assessment of medicines, which aims to obtain a partnership with patients to achieve drug treatment goals and agreement about drug dosage, as well as when and how the drugs should be administered. The objective was to analyze the influence of pharmacotherapy review, by scheduling drug administration to improve medication adherence among antihypertensive patients. This study was an uncontrolled intervention developed in three distinct stages. The first stage included data collection on the profile of patients and their medications, and a preliminary assessment of medication adherence. In the second stage, the review report was delivered to patients. In the third stage, the results of blood pressure and medication adherence were assessed. The influence of the revision was measured through statistical tests (p<0.05). The study included 40 patients with a mean age of 58.0 (SD:11.3) years; 72.5% were women. Thirty-three (82.5 %) patients required some intervention, after when there was a significant increase in the number of daily doses (p=0.039) and drug intakes (p=0.025). There was a significant increase in the adherence rate, according to both the Morisky-Green test (p<0.001) and self-reported assessment (p=0.004). There was also an improvement in the levels of systolic (p<0.001) and diastolic (p=0.002) blood pressure and in the number of patients with controlled hypertension (p=0.006). The pharmaceutical service enhanced medication adherence and control of systemic blood pressure; however, it increased the complexity of treatment

On the role of the upper part of words in lexical access : evidence with masked priming

More than 100 years ago, Huey (1908) indicated that the upper part of words was more relevant for perception than the lower part. Here we examined whether mutilated words, in their upper/lower portions (e.g., , , , ), can automatically access their word units in the mental lexicon. To that end, we conducted four masked repetition priming experiments with the lexical decision task. Results showed that mutilated primes produced a sizeable masked repetition priming effect. Furthermore, the magnitude of the masked repetition priming effect was greater when the upper part of the primes was preserved than when the lower portion was preserved –this was the case not only when the mutilated words were presented in lowercase but also when the mutilated words were presented in uppercase. Taken together, these findings suggest that the front-end of computational models of visual-word recognition should be modified to provide a more realistic account at the level of letter features.The research reported in this article has been partially supported by Grant PSI2008-04069/PSIC and CONSOLIDER-INGENIO2010 CSD2008-00048 from the Spanish Ministry of Science and Innovation and by Grant PTDC/PSI-PCO/104671/2008 from the Portuguese Foundation for Science and Technology