McGill University Thèses et mémoires publiés en 1996

This thesis investigates the economic and military policies hegemons pursue while experiencing relative decline. Based upon the rising costs of leadership associated with hegemony, this thesis establishes that both systemic and domestic environments equally influence the hegemon's policy-making. Furthermore, the paper contends that hegemons do practice strategic planning during relative decline, in an effort to adjust its commitments and resources to the environment. Relative success or failure in maintaining the international system and thus adjusting for decline depends on how decision-makers compensate for two prevailing variables: threat of challengers and availability of allies. This study offers a predictive theoretical model …  Lire la suite

The United Nations Convention on International Multimodal Transport of Goods of 24th May 1980 is an appropriate answer to the legal and political problems raised by through carriage and containerisation. Traditionally, when goods were transferred from one mode to another they were also transferred to a new legal regime. There was no coherent legal regime governing carrier liability for goods moving in multimodal transport. The Convention creates a new liability system and confer international legal sanction on the responsibilities and immunities flowing from the multimodal transport contract. The Convention compromises between the needs of developing countries--who called for provisions on …  Lire la suite

This thesis is an attempt to assess the importance of the satirical photo essay Deutschland, Deutschland uber alles in the life and literary development of the German author Kurt Tucholsky, and to help establish the significance of the work in the German literary canon. The work appeared in 1929, and marked a complete departure from his previous output in many respects. He experimented with the genre of photo essay and photomontage in collaboration with renowned montage artist and dedicated Communist John Heartfield, attempted to reach a new reading audience in the German working classes, and published the book in a …  Lire la suite

This research is one of a group of studies which aims to evaluate the feasibility of disinfection using ultraviolet radiation (UV) at the Montreal Urban Community Wastewater Treatment Plant (MUCWTP), and to provide information to evaluate the level of disinfection required. The physico-chemically treated effluent is discharged into the St. Lawrence River. The downstream river is used for recreational purposes, particularly at Ile Evers (4 km downstream), which is occasionally used as a beach. The distributions of fecal coliforms (FCs) in the river relative to their distribution in the effluent were assessed in terms of those that were particle-associated FCs …  Lire la suite

The Wilms' tumor suppressor gene 1 (wt1) encodes a transcription factor belonging to the Early Growth Response (EGR) family of proteins. The gene produces an mRNA that is alternatively spliced to yield four different species. In this thesis, it is shown that the wt1 gene has two sites of translational initiation, an AUG codon and a CUG codon that is upstream of and in frame with the AUG codon. The combination of alternative initiation sites and alternatively spliced exons allows the gene to encode eight different isoforms. It was previously shown that heterozygous mutations of wt1, predicted to result in …  Lire la suite

A study was undertaken from 1993 to 1994 to determine the effects of intercropping (with Glycine max L Merr., Lupinus sp., Trifolium pratense L.-Lolium multiflorum Lam., or Secale cereale L.) and mechanical weeding (with a rigid tines cultivator, Danish tines cultivator or ridge cultivator) on the population dynamics of insect pests (Diabrotica longicornis Say, Lygus lineolaris Palisot de Beauvois, Ostrinia nubilalis Hubner, and Pseudaletia unipuncta Haworth) on corn (Zea mays L.) in L'Assomption and Sainte-Anne-de-Bellevue, Quebec, Canada. D. longicornis or P. unipuncta populations did not increase. In 1994, intercropping with T. pratense-L. multiflorum (Sainte-Anne-de-Bellevue) or weeding with the Danish tines …  Lire la suite

Gallium arsenide, a compound semiconductor commonly used in optoelectronic devices, is often subjected to wet etching techniques during microelectronic device manufacture. In this work, the wet chemical etching of gallium arsenide in $ rm H sb2O sb2$-$ rm NH sb4OH$-H$ sb2$O solutions was studied using a batch stirred-tank reactor. A kinetic control regime was established and the influence of each component's concentration on the intrinsic etch rate was determined. The reaction rate was found, in the presence of excess NH$ sb4$OH, to fit a rate equation, r = k (H$ rm sb2O sb2 rbrack sp{0.75}$ at 15, 25, and 40$ …  Lire la suite

Horseradish peroxidase (HRP) catalyzes the polymerization of aromatic compounds. These polymers precipitate from solution and may be removed by filtration or sedimentation. The useful lifetime of the enzyme is limited by inactivation which occurs during the removal process; however, the rate of enzyme inactivation is significantly lower in the presence of high molecular mass polyethylene glycol (PEG). An empirical model has been developed to relate phenol concentration after complete batch reaction to the initial concentrations of phenol and HRP, both in the presence and the absence of PEG. A kinetic model has been developed for the removal process. Enzyme inactivation …  Lire la suite

This study was designed to determine the potential biological effects of electric and magnetic fields (EMF), generated by 735 kV alternating current (AC) high tension lines upon the hormonal profile, some health-related parameters, stress response and productivity in dairy cattle. An EMF exposure chamber to house eight animals at one time was constructed. Forty-nine cows were divided according to their production stage; 8 pregnant non-lactating cows, 16 pregnant lactating cows, 16 non-pregnant lactating cows and 9 non-lactating non-pregnant heifers. They were exposed to an EMF of 10 kilovolts per meter (kV/m) and 30 micro-Tesla $( mu T)$ in two different …  Lire la suite

Daneshmend, L. (Supervisor)  Lire la suite

Hagiography occupies a central place in the history of European culture, and yet despite this centrality, its reception as a significant cultural achievement has at times been undermined by a narrow critical hermeneutic, one that focuses largely on the debilitating flaws of the genre. The goal of this critical practice can be described as at once diagnostic and prescriptive, as scholars attempt to rid the canon of specious documents through rigorous textual and contextual analyses. It is my contention, however, that this critical winnowing, rather than rescuing some hagiographic documents from disrepute, is in fact limited by its failure to …  Lire la suite

$ alpha$1,2-Mannosidases are a family of enzymes with similar amino acid sequences that are required for the formation of complex and hybrid asparagine-linked oligosaccharides in mammalian cells. We have determined the genomic structure of one member of this enzyme family, the murine $ alpha$1,2-mannosidase IB gene. Two BALB/c cosmid genomic clones (Cos.31.1 and Cos.25.1) and three overlapping 129/sv P1 genomic clones were isolated. Analysis of Cos.31.1 and the P1 clones showed that the $ alpha$1,2-mannosidase IB gene spans 180kb of the genome, and consists of 13 exons representing the complete open reading frame of the enzyme. Comparison of the intron/exon …  Lire la suite

Moslowe (Supervisor)  Lire la suite

Because they occur in the contentious public arena that surrounds abortion, the development, introduction, and use of RU486, also known as "the abortion pill," provide a valuable opportunity for understanding how sociotechnical analysis can contribute ta the study of communication phenomena. The essay presents a preliminary case study of RU486 in Canada, drawing on an earlier U.S. study performed by Adele Clarke and Therese Montini (1993), supplemented by Bruno Latour's actor network theory and Ruth Schwartz Cowan's framework for linking gender, technology and public policy. [...]  Lire la suite

Schistosoma mansoni and Fasciola hepatica are parasitic trematodes which contain cytochrome c peroxidase (CcP) in their mitochondria, an enzyme that is absent in mammalian tissues. CcP reduces hydrogen peroxide to H2O using cytochrome c as the electron donor. Both parasites are catalase deficient; thus, cytochrome c peroxidase and glutathione peroxidase are the enzymes involved in the detoxification of H2O 2 in these organisms. The enzymatic activity of these two peroxidases may enable S. mansoni and F. hepatica to survive oxidative stress. The main objective of this study was to characterize cytochrome c peroxidase from S. mansoni and F. hepatica . …  Lire la suite

With the improvement of working conditions in asbestos industries and the recognition that asbestos exposure is widespread, the asbestos controversy has shifted in the 1980s to the general environment. To assess lung cancer risks due to environmental asbestos exposure, risks in past asbestos workers have been extrapolated linearly to exposures 100,000 times smaller than historical occupational levels. Despite their enormous health and economic impact, such risk assessments have not been validated to this day. This is the first study to compare the risk of lung cancer in a population non-occupationally exposed to asbestos with those predicted by the U.S. Environmental …  Lire la suite

On-line ultrasonic monitoring of injection molding of polyethylene and die casting of aluminum is studied using pulse-echo techniques. The flow front of molten materials including the polymers and aluminum inside the mold has been probed by a multiple-channel probing system with a time resolution of about 1 ms. This information can be used to control the plunger movements. The gap development which is important for the understanding of the thermal contact between the mold and the part due to the shrinkage is also monitored. Gap formation time periods versus different packing pressure and at different part locations with different part …  Lire la suite

Three studies were conducted in which Quebec French, first grade children's ability to categorize vowels was examined. The children were tested on several aspects of vowel phoneme representation before they had any literacy skills, at the beginning of the school year, and again sis months later, after they had learned all of the spelling-sound correspondences for vowels. In Study 1, the focus was on children's phonemic and orthographic representation of nasal vowels. Performance on an AXB categorization task revealed that six-year-olds have considerable difficulty in discriminating the nasal feature on minimal and near-minimal oral-nasal vowel pairs. This ability did not …  Lire la suite

Van De Ven, T. G. M. (Supervisor)  Lire la suite

Zhang, Da-Lin (Supervisor)  Lire la suite

This study examined the effectiveness of an adaptation of Melodic Intonation Therapy (MIT) in increasing the communicative speech of young children with Down syndrome. Eight children were matched according to their mean length of utterance and divided into two groups, the melodic group and the spoken group. The same individual treatment was received by all during twelve weekly sessions, except for the manner in which target phrases were presented: spoken versus melodically intoned. Data was collected from language samples taken before and after treatment as well as from audiotapes of the children's verbal responses produced during the weekly sessions. Findings …  Lire la suite

The intercropping of corn with legumes is an alternative cropping strategy to corn monocropping which may help reduce inputs into the production of silage for livestock feed. The reduction of inputs will decrease costs to producers and potential damage to the environment. Two experiments were carried out at each of two sites in 1993 and 1994. The first experiment investigated the effects on silage yield and weed control of seeding soybean or lupin alone or in combination with one of three forages (annual ryegrass, Lolium multiflorum Lam.; perennial ryegrass, Lolium perenne L.; and red clover, Trifolium pratense L.). The second …  Lire la suite

Denaturing gradient gel electrophoresis (DGGE) and sequencing of the PAH locus has found 38 different mutations on 141 chromosomes in the PKU patients resident in Quebec; mutation analysis is now 92.5% complete. Two novel disease producing alleles (K421, R157N) and one silent allele (IVS6 nt-55) were discovered in this project; these mutations remain unique to the Quebec population. Three novel mutation-(haplotype) combinations were also found (S67P (H1), G218V (H2), V245A (H7)); they are not at hypermutable sites and are therefore compatible with a single homologous recombination event between two different haplotypes. Whereas mutation types (missense 64%, nonsense 6%, splice 9%, …  Lire la suite

Batch washing experiments were used to evaluate extractive decontamination of heavy metal polluted illite soils using ethylenediamine-tetraacetic acid (EDTA) and trans 1,2 cyclohexylenedinitrilo-tetraacetic acid (CDTA). Five series of contaminated illite soils were prepared through adsorption tests using four single-specie 5000 ppm heavy metal solutions of Pb, Cu, Zn, or Cd and one multi-species solution containing 1250 ppm of each heavy metal. The five contaminated illite soils that were prepared contained the following levels of heavy metals per kilogram of soil: (i) 5000 mg Pb, (ii) 3490 mg Cu, (iii) 1566 mg Zn, (iv) 700 mg Cd, (v) 1186 mg Pb; …  Lire la suite

This thesis elaborates on existing definitions and descriptions of simulation to develop an extended, inter-disciplinary concept of simulation that serves as an orienting model for the interpretation of culture. As cultural theory, simulation offers insights into the stabilization and propagation of cultural forms. Used descriptively, the metaphor of simulation throws into definition a cultural pattern of progressive formalization through increasingly sophisticated methods of abstraction. I find evidence of the pattern at many levels of analysis; metaphysical, social and micro-social, particularly at the level of the body. I use the speculative notion of the digital refiguring of culture to articulate this …  Lire la suite

The goals of the research work presented in this thesis were (i) to determine the accuracy of lateralization of temporal lobe epilepsy (TLE) by proton magnetic resonance spectroscopic imaging (MRSI) and magnetic resonance imaging (MRI) based volumetric measurements (MRIVol) in comparison with the current "gold standard" of clinical-EEG lateralization, (ii) to optimize the sensitivity of the MRSI and MRI methods (iii) to examine the surgical outcome in groups of patients undergoing surgical treatment, and (iv) to provide insights into the pathogenesis of partial epilepsies. Early on we confirmed the usefulness of measuring hippocampal formation (HF) volumes in the lateralization of …  Lire la suite

Several studies have shown that the retinoic acid (RA)-activated signaling pathway can interact with both the PKA and the PKC signaling pathways. The aim of this project was to investigate the mechanism of such an interaction in the differentiation of P19 and RAC65 murine embryonal carcinoma cells. Two activators and two inhibitors of both PKA and PKC were used in differentiation experiments. Of these eight modulators, only the PKA activator dibutyryl cyclic adenosine monophosphate (dbcAMP) and the PKC inhibitor sphingosine were found to significantly potentiate the effect of RA in the neuronal cell differentiation of these cells. However, neither of …  Lire la suite

The present thesis investigates the effects of lesions to several hypothesized learning and memory systems on the morphine conditioned cue preference on the radial maze. Lesions of the structures thought to be centered to learning systems: the lateral nucleus of amygdala, fornix/fimbria, anterior dorsal striatum and posterior dorsal striatum, were made, In Experiment One, each structure was lesioned separately. Only lesions of the lateral nucleus of amygdala blocked morphine CCP learning. In Experiment Two, rats with combined lesions of fornix/fimbria and dorsal striatum, the lateral nucleus of amygdala and fornix/fimbria, as well as the lateral nucleus of amygdala and dorsal …  Lire la suite

Bien qu ‘il y a beaucoup d’études sur le conflit à long-terme, i.e., ‘La Théorie de Rivalité de Longue Durée ‘ et ‘ La Théorie du Conflit Prolongé ‘, la littérature souffre d ‘une négligence d ‘une dimension décisionnelle dans un tel conflit. Cette dissertation porte sur la décision de la politique étrangère sur le conflit prolongé. La question centrale est: qu’est-ce qui crée, prolonge, et termine un tel conflit? Le conflit Coréen, 1948-1993, est une étude d’un tel cas. Cette étude présente les arguments qui tous deux: l’intérêt national et l’identité sont des sources de conflit prolongé, ainsi que …  Lire la suite

It is commonly assumed that the development of tourist attractions, the formulation of tourism policies and the marketing of destination areas are dictated by the needs and interests of foreign visitors. What is ignored is the role that local factors and agencies bring to bear upon the process. This thesis is devoted to exploring the ways that local and non-local factors are responsible for shaping the form and function of tourism development. Drawing upon the case of Singapore, the thesis examines the country's heritage tourism phenomena as the outcome of 'local' and 'global' forces. This argument is elaborated along four …  Lire la suite

Our search for protein tyrosine phosphatases (PTPases) that are involved in murine development led to the isolation of a novel PTPase called MPTP-PEST. To elucidate the function of MPTP-PEST, several biological aspects of the protein were investigated. It was determined that the MPTP-PEST enzyme is a stable cytosolic protein tyrosine phosphatase of 112 kDa that is ubiquitously expressed both in the adult and in the embryo. MPTP-PEST is composed of a single amino-terminus catalytic domain which is active against phosphorylated substrates in vitro. The gene structure and chromosomal localization of MPTP-PEST were determined using a series of $ lambda$ phage …  Lire la suite

Iron is recognized as a key element regulating primary production in large regions of the ocean, but nothing is known of its direct effect on higher trophic levels. Growth and metabolism of two species of heterotrophic protozoans fed iron-rich and iron-poor prey were thus examined. Maximum growth rates of Paraphysomonas imperforata and P. butcheri were observed only when Fe quotas of bacterial prey were greater than 70 $ mu$mol Fe:mol C. At lower Fe:C ratios, but at constant prey biomass (C/ml), both species grew significantly slower. Minimum Fe quotas of the flagellates at these slow growth rates ($ sim$10 $ …  Lire la suite

The Innuulisivik: maternity is a northern based service in Povungnituk, Quebec which serves the Inuit women of the Hudson Coast. Although most women stay in the north for childbirth, others are transferred south. This thesis will describe the experience of the Innuulisivik: maternity which uses committee based risk assessment for transfer decisions. Data for the three year period 1989 -1991 were examined. Descriptive statistics were used to compare the observed differences in the distribution of several variables according to birthplace. Data were available for 411 women. 350 (85.2%) of the births occurred at Innuulisivik, 44 (10.7 %) women were transferred …  Lire la suite

Cette thèse est une étude du cycle de romans apocalyptiques de Leopoldo Marechal, cycle qui se compose d'Adan Buenosayres (1948) et sa suite dialectique, El Banquete de Severo Arcangelo (1965). Ce dernier, qui reconte une apocalypse burlesque, se signale surtout grâce à la lumière qu'il fait sur le premier. En plus, est considérée ici, à titre de coda du cycle apocalyptique, la partie de l'œuvre posthume, Megafon, o la guerra (1970) qui s'y rapporte par son thème. […]  Lire la suite

Cette monographie porte sur l'analyse de l'influence d'une langue seconde; le français sur une langue premiére - l'arabe algérien. Cette influence est représentée par les emprunts du français en arabe algérien et le mélange des codes de ces deux_ langues. Nous constatons qu'il y a diverses assimilations et adaptations linguistiques qui s'opèrent lors des emprunts au niveau des emprunts et du mélange des codes.  Lire la suite

Association between albendazole anthelmintic resistance and a panel of life history traits in Heligmosomoides polygyrus was investigated both prior to and during drug-selection. Associations prior to anthelmintic application were studied in ten independent lines isolated without drug treatment from a susceptible stock population by random genetic drift. Variation among lines was detected in several life history traits (i.e., establishment, development and survival), and, despite lack of previous exposure to albendazole, lines also varied in their tolerance to the drug. No significant correlations were detected between drug-tolerance and any of the life history traits after 11 generations of isolation. The apparent …  Lire la suite

Travis, Lista (Supervisor)  Lire la suite

Enamel is produced by a layer of ectodermally derived cells called ameloblasts. These cells first create the entire thickness of enamel in the form of a protein-rich, partially mineralized extracellular layer. During the maturation stage, most of the proteins are degraded and replaced by mineral. At least three types of proteins--amelogenins, enamelins/non-amelogenins/tuftelins, and proteinases--are believed to be involved in enamel formation, but the exact number of secretory proteins produced by ameloblasts and the changes in molecular weight these proteins undergo in traversing the secretory pathway and following their release extracellularly are still very controversial. The purpose of this investigation was …  Lire la suite

Multiple Organ Dysfunction Syndrome (MODS) is associated with high mortality in patients admitted to the surgical intensive care unit (SICU). MODS begins with a systemic response described as Systemic Inflammatory Response Syndrome (SIRS). Studies on SIRS patients may provide an insight into the mechanisms by which SIRS progresses to MODS. In this thesis, the interactions between circulating polymorphonuclear neutrophils (PMNs) from patients with SIRS and endothelial cells (ECs) from human umbilical veins were measured in order to elucidate the mechanism for PMN adhesion and subsequent cytotoxicity of the ECs. PMNs from patients with SIRS were compared to PMNs from pre-operative …  Lire la suite

Following survey of the literature on the subject of internship, this study reports the findings on a Canadian-wide survey of organizations providing internship to cooperating educational institutions. The findings point clearly to the high degree of importance these organizations attach to internship and the high level of attention and resources that they commit to supervision of interns. They also point to an absence of full understanding of the role of internship and what it can potentially accomplish for both the interns and the participating organizations. In order to fully realize these potentials, the study proposes suggestions to coordinate internship amongst …  Lire la suite

Polyomavirus large T antigen binds to four adjacent sites on viral DNA, denoted 1/2, A, B and C. Binding to site 1/2 leads to the initiation of viral DNA replication. RNA polymerases transcribing the late strand of the circular, 5.3 kb viral DNA are blocked just upstream of the replication origin and stalled RNA polymerases accumulate in that region (Skarnes et al., J. Mol. Biol. 203: 153-171, 1988). This accumulation of stalled RNA polymerases depends on binding of large T antigen to site A but not B or C (Bertin et al., J. Virol. 67:5766-5775, 1993). To investigate whether this …  Lire la suite

The reactivities of two dinuclear metals complexes with bridging hydroxides for hydrolyzing phosphrite diesters have been examined. The second-order rate constants ($ rm k sp prime sb{hyd}/M sp{-1} s sp{-1}$) for the hydroxidecatalysed hydrolysis of bridging aryl methyl phosphates in di-$ mu$-hydroxodinuclear cobalt(III) complex ($ rm Co sb2( lbrack 9 rbrack aneN sb3) sb2(OH) sb2(OP(O)(OMe)(OAr) rbrack sp{3+}$ ( (9) aneN$ sb3$ = 1,4,7-triazacyclononane) and the corresponding free aryl methyl phosphates (25$ sp circ$C and 0.1 M ionic strength) obey the following Bronsted equations: eqalign{ rm log k sp prime sb{hyd} (free diester) = -0.70 pK sb{ rm a}-0.66 & quad …  Lire la suite

Advanced research in Controlled/Modified Atmosphere storage systems has shown that open channels of different lengths and cross sectional areas, connected to an air tight storage chamber, are able to maintain variable stable gas concentrations which could be near optimal concentrations for CA/MA storage of various commodities. This study was geared towards assessing the suitability of the diffusion channels in maintaining a desired gas concentration for CA storage of spinach. Initially, the respiratory behaviour of spinach was studied in gas sealed chambers (replicated four times) stored at four different temperatures, 2$ sp circ$C, 8$ sp circ$C, 15$ sp circ$C and 23$ …  Lire la suite

The sol-gel process is a low temperature solution route to amorphous and crystalline materials. Organic modification of the precursors allows the formation of organic-inorganic composite materials. We use the sol-gel process to produce an organically-modified ceramic for integrated optical applications. Photosensitive organic components allow the fabrication of passive integrated optical devices by photolithography. We demonstrate the fabrication and characterization of channel waveguides, waveguide devices and gratings in this material. Active devices based on the emission of erbium at 1.55 $ mu$m are under much investigation because of their potential use in telecommunications. Luminescence quenching is a major problem as an …  Lire la suite

A search of the Saccharomyces genome data base revealed an open reading frame of 2039 amino acids with homology to L-type calcium channels. Northern blots probed with a 540 bp PCR product of the ORF showed a transcript of 6.1 kb. Two procedures were used to disrupt the gene: the ORF was truncated by an integrative disruption after the third pore motif, or deleted in the first three pore domains using a one-step disruption construct. In most strains tested, the disruptions gave no apparent phenotype when tested under a variety of conditions. However, conspicuous phenotypes were seen in the strain …  Lire la suite

In the aeronautical applications, many problems involving boundaries of unspecified geometry are of interest, such as the indirect problems of determining the shape of an airfoil to generate a specified pressure distribution, supersonic nozzle design based on reflection-suppression condition, flexible-membrane airfoils or wings, jet-flapped airfoils, and others. In these cases, the utilization of the Eulerian formulations of the Euler equations of motion, may lead to long iterative computations for successive shapes of the boundaries, until the final geometry is reached. For this type of problems, the Lagrangian formulations using the streamline coordinates are more suitable, since the geometrically-unspecified boundaries are …  Lire la suite

An adaptive finite element method is developed to solve two dimensional unbounded electromagnetic radiation and scattering problems. Though there has been considerable research in adaption in electromagnetics, to date there have been few attempts to deal with adaptively reducing the error introduced by the boundary that artificially truncates the unbounded domain in a finite element analysis. The technique proposed here adapts on this boundary error, as well as on the usual finite element discretization error. It combines three techniques: (i) p-adaptive hierarchial triangular finite elements, (ii) wave-envelope elements and (iii) absorbing boundary conditions. Hierarchial finite elements allow the polynomial orders …  Lire la suite

A total of 853 milk samples with different phenotypes of $ kappa$-casein ($ kappa$-CN) and $ beta$-lactoglobulin ($ beta$-LG) and different preheating temperatures of 30, 70, 75 and 80$ sp circ$C were used for the making of individual laboratory scale Cheddar type cheese and for the determination of coagulating properties. Data obtained from milk input, cheese output and chemical analyses were used to calculate actual, 37% moisture adjusted and Van Slyke's theoretical yields and yield efficiency. Least squares analyses of data indicated that higher 37% moisture adjusted yields and yield efficiencies were obtained with milk types VII, VIII and IX, …  Lire la suite

Bray, Garth M. (Supervisor)  Lire la suite

Neurofibromatosis type 2 (NF2) is a dominantly inherited genetic disorder predisposing to the development of nervous system tumors such as bilateral vestibular schwannomas, cranial and spinal meningiomas, nerve root schwannomas and ependymomas. The majority of NF2 patients develop juvenile lens opacities often presenting prior to the development of tumors usually in early teens. The NF2 gene had been identified by positional cloning. It encodes a recessive tumor suppressor protein mutated in both sporadic and familial schwannomas and meningiomas. We have isolated the mouse homologue of the NF2 gene (Nf2) from an 18-day old mouse brain cDNA library. Nf2 encodes a …  Lire la suite