An Exact Bosonization Rule for c=1 Noncritical String Theory

We construct a string field theory for c=1 noncritical strings using the loop variables as the string field. We show how one can express the nonrelativistic free fermions which describes the theory, in terms of these string fields.Comment: 17 pages, to appear in JHE

Mutations in SRY and WT1 genes required for gonadal development are not responsible for XY partial gonadal dysgenesis

The WT1 transcription factor regulates SRY expression during the initial steps of the sex determination process in humans, activating a gene cascade leading to testis differentiation. In addition to causing Wilms' tumor, mutations in WT1 are often responsible for urogenital defects in men, while SRY mutations are mainly related to 46,XY pure gonadal dysgenesis. In order to evaluate their role in abnormal testicular organogenesis, we screened for SRY and WT1 gene mutations in 10 children with XY partial gonadal dysgenesis, 2 of whom with a history of Wilms' tumor. The open reading frame and 360 bp of the 5' flanking sequence of the SRY gene, and the ten exons and intron boundaries of the WT1 gene were amplified by PCR of genomic DNA. Single-strand conformation polymorphism was initially used for WT1 mutation screening. Since shifts in fragment migration were only observed for intron/exon 4, the ten WT1 exons from all patients were sequenced manually. No mutations were detected in the SRY 5' untranslated region or within SRY open-reading frame sequences. WT1 sequencing revealed one missense mutation (D396N) in the ninth exon of a patient who also had Wilms' tumor. In addition, two silent point mutations were found in the first exon including one described here for the first time. Some non-coding sequence variations were detected, representing one new (IVS4+85A>G) and two already described (-7ATG T>G, IVS9-49 T>C) single nucleotide polymorphisms. Therefore, mutations in two major genes required for gonadal development, SRY and WT1, are not responsible for XY partial gonadal dysgenesis.172

Self-energy and Self-force in the Space-time of a Thick Cosmic String

We calculate the self-energy and self-force for an electrically charged particle at rest in the background of Gott-Hiscock cosmic string space-time. We found the general expression for the self-energy which is expressed in terms of the $S$ matrix of the scattering problem. The self-energy continuously falls down outward from the string's center with maximum at the origin of the string. The self-force is repulsive for an arbitrary position of the particle. It tends to zero in the string's center and also far from the string and it has a maximum value at the string's surface. The plots of the numerical calculations of the self-energy and self-force are shown.Comment: 15 pages, 4 Postscript figures, ReVTe

Analytical approximation of the stress-energy tensor of a quantized scalar field in static spherically symmetric spacetimes

Analytical approximations for ${}$ and ${}$ of a quantized scalar field in static spherically symmetric spacetimes are obtained. The field is assumed to be both massive and massless, with an arbitrary coupling $\xi$ to the scalar curvature, and in a zero temperature vacuum state. The expressions for ${}$ and ${}$ are divided into low- and high-frequency parts. The contributions of the high-frequency modes to these quantities are calculated for an arbitrary quantum state. As an example, the low-frequency contributions to ${}$ and ${}$ are calculated in asymptotically flat spacetimes in a quantum state corresponding to the Minkowski vacuum (Boulware quantum state). The limits of the applicability of these approximations are discussed.Comment: revtex4, 17 pages; v2: three references adde

Emergent geometry from q-deformations of N=4 super Yang-Mills

We study BPS states in a marginal deformation of super Yang-Mills on R x S^3 using a quantum mechanical system of q-commuting matrices. We focus mainly on the case where the parameter q is a root of unity, so that the AdS dual of the field theory can be associated to an orbifold of AdS_5x S^5. We show that in the large N limit, BPS states are described by density distributions of eigenvalues and we assign to these distributions a geometrical spacetime interpretation. We go beyond BPS configurations by turning on perturbative non-q-commuting excitations. Considering states in an appropriate BMN limit, we use a saddle point approximation to compute the BMN energy to all perturbative orders in the 't Hooft coupling. We also examine some BMN like states that correspond to twisted sector string states in the orbifold and we show that our geometrical interpretation of the system is consistent with the quantum numbers of the corresponding states under the quantum symmetry of the orbifold.Comment: 22 pages, 1 figure. v2: added references. v3:final published versio

Conductance distribution in disordered quantum wires: Crossover between the metallic and insulating regimes

We calculate the distribution of the conductance P(g) for a quasi-one-dimensional system in the metal to insulator crossover regime, based on a recent analytical method valid for all strengths of disorder. We show the evolution of P(g) as a function of the disorder parameter from a insulator to a metal. Our results agree with numerical studies reported on this problem, and with analytical results for the average and variance of g.Comment: 8 pages, 5 figures. Final version (minor changes

Morphometry And Histology Of Gonads From 13 Children With Dysgenetic Male Pseudohermaphroditism

Background. - Dysgenetic male pseudohermaphroditism (DMP) is a sexual differentiation disorder characterized by bilateral dysgenetic testes, persistent müllerian structures, and cryptorchidism in individuals with a 46,XY karyotype. However, the histologic criteria for the diagnosis of DMP are poorly established. Objective. - To determine gonadal histology in children with DMP. Patients and Methods. - Between 1996 and 1998, 13 patients with DMP were evaluated on our service. The clinical diagnosis of DMP was based on a 46,XY karyotype, sex ambiguity, high levels of follicle-stimulating hormone and low levels Of antimüllerian hormone, a decreased testosterone response to human chorionic gonadotropin stimulation without accumulation of testosterone precursors, and the presence of müllerian structures. Molecular sequencing the HMGbox region of the SRY gene did not reveal any mutations. Biopsies were performed for 22 of 26 gonads (patient age at the time of biopsy, 16 months to 10 years). Conventional microscopy was used to evaluate mean tubular diameter, tubular fertility index, and number of Sertoli cells per tubular profile. Results. - All 26 gonads were located outside of the labioscrotal folds. Their histologic features varied from only a reduction in tubular size to features of a streak gonad. Five of the 22 gonads grossly resembled a streak gonad. The mean tubular diameter was severely reduced (>30% reduction relative to the normal tubular diameter for the patient's age) in 4 gonads, markedly reduced (10%-30%) in 11 gonads, slightly reduced (<10%) in one gonad, and normal in one gonad. The tubular fertililty index, expressed as the percentage of tubular profiles containing germ cells, was severely reduced (<30% of normal values) in 9 gonads, markedly reduced (50%-30%) in 2 gonads, and normal in 6 gonads. The number of Sertoli cells per tubular profile was elevated in 16 gonads and normal in one gonad. Thin tubules surrounded by fibrous tissue were occasionally observed. Conclusion. - The histologic findings confirmed the clinical diagnosis of DMP in every patient in the present series. However, gonadal histology was variable, and careful morphometric evaluation may be necessary to establish the diagnosis.1255652656Robboy, S.J., Miller, T., Donahoe, P.K., Dysgenesis of testicular and streak gonads in the syndrome of mixed gonadal dysgenesis: Perspective derived from clinicopathologic analysis of twenty-one cases (1982) Hum Pathol, 13, pp. 700-716Troche, V., Hernandez, E., Neoplasia arising in dysgenetic gonads (1986) Obstet Gynecol Surv, 41, pp. 74-79Krasna, I.H., Lee, M.L., Smilow, P., Sciorra, L., Eierman, L., Risk of malignancy in bilateral streak gonads: The role of the Y chromosome (1992) J Pediatr Surg, 27, pp. 1376-1380Rohatgi, M., Gupta, D.K., Menon, P.S., Verma, I.C., Mathur, M., Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism - A critical analysis (1992) Indian J Pediatr, 59, pp. 487-500Rey, R.A., Belville, C., Nhou-Fékété, C., Evaluation of gonadal function in 107 intersex patients by means of serum antimüllerian hormone measurement (1999) J Clin Endocrinol Metab, 84, pp. 627-631Stuchi-Perez, E.G., Lukas-Croisier, C., Castro, M., Evaluation of the tubular and interstitial functions of the testis in 46,XY patients with ambiguous genitalia (2000) J Pediatr Endocrinol Metab, 13, pp. 605-612Chang, H.J., Clark, R.D., Bachman, H., The phenotype of 45,X/46,XY mosaicism: An analysis of 92 prenatally diagnosed cases (1990) Am J Hum Genet, 46, pp. 156-167Rajfer, J., Walsh, P.C., Mixed gonadal dysgenesis: Dysgenetic male pseudoher-maphroditism (1981) The Intersex Child: Pediatric and Adolescent Endocrinology, pp. 103-115. , Josso N, ed. Basel, Switzerland: S. KargerBorer, J.G., Nitti, V.W., Glassberg, K.I., Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism (1995) J Urol, 153, pp. 1267-1273Donahoe, P.K., Crawford, J.D., Hendren, W.H., Mixed gonadal dysgenesis: Pathogenesis and management (1979) J Pediatr Surg, 14, pp. 287-300Pelletier, J., Bruening, W., Kashtan, C.E., Germline mutations in the Wilms' tumor supressor gene are associated with abnormal urogenital development in Denys-Drash syndrome (1991) Cell, 67, pp. 437-1147Carré-Éusebe, D., Imbeaud, S., Harbison, M., New, M.I., Josso, N., Picard, J.Y., Variants of the anti-Müllerian hormone gene in a compound heterozygote with the persistent Müllerian duct syndrome and his family (1992) Hum Genet, 90, pp. 389-394Nistal, M., Paniagua, R., Non-neoplastic diseases of the testis (1996) Urologic Surgical Pathology, pp. 458-565. , Bostiwick DG, Eble JN, eds. St Louis, Mo: MosbyLennox, B., Ahmad, K.M., Mack, W.S., A method for determining the relative total length of the tubules in the testis (1970) J Pathol, 102, pp. 229-238Jimenez, R., Sanchez, A., Burgos, M., Dias De La Guardia, R.C., Puzzling out the genetics of mammalian sex determination (1996) Trends Genet, 12, pp. 164-166Müller, J., Skakkebaek, N.F., Quantification of germ cells and seminiferous tubules by stereological examination of testicles from 50 boys who suffered from sudden death (1983) Int J Androl, 6, pp. 143-156Cortes, D., Müller, J., Skakkebaek, N.E., Proliferation of Sertoli cells during development of the human testis assessed by stereological methods (1987) Int J Androl, 10, pp. 589-596Nistal, M., Abaurrea, M.A., Paniagua, R., Morphological and histometric study on the human Sertoli cell from birth to the onset of puberty (1982) J Anat, 14, pp. 351-363Van Niekerk, W.A., Retief, A.E., The gonads of human true hermaphrodites (1981) Hum Genet, 58, pp. 117-122Guerra Jr., G., De Mello, M.P., Assumpção, J.G., True hermaphrodites in the southeastern region of Brazil: A different cytogenetic and gonadal profile (1998) J Pediatr Endocrinol Metab, 11, pp. 519-524Quigley, C.A., De Bellis, A., Marschke, K.B., El-Awady, M.K., Wilson, E.M., French, F.S., Androgen receptor defects: Historical, clinical and molecular perspectives (1995) Endocr Rev, 16, pp. 271-32

Monte Carlo approach to nonperturbative strings -- demonstration in noncritical string theory

We show how Monte Carlo approach can be used to study the double scaling limit in matrix models. As an example, we study a solvable hermitian one-matrix model with the double-well potential, which has been identified recently as a dual description of noncritical string theory with worldsheet supersymmetry. This identification utilizes the nonperturbatively stable vacuum unlike its bosonic counterparts, and therefore it provides a complete constructive formulation of string theory. Our data with the matrix size ranging from 8 to 512 show a clear scaling behavior, which enables us to extract the double scaling limit accurately. The ``specific heat'' obtained in this way agrees nicely with the known result obtained by solving the Painleve-II equation with appropriate boundary conditions.Comment: 15 pages, 10 figures, LaTeX, JHEP3.cls; references added, typos correcte

Two-dimensional superstrings and the supersymmetric matrix model

We present evidence that the supersymmetric matrix model of Marinari and Parisi represents the world-line theory of N unstable D-particles in type II superstring theory in two dimensions. This identification suggests that the matrix model gives a holographic description of superstrings in a two-dimensional black hole geometry.Comment: 22 pages, 2 figures; v2: corrected eqn 4.6; v3: corrected appendices and discussion of vacua, added ref

Clinical outcomes of patients with acute myeloid leukemia: evaluation of genetic and molecular findings in a real-life setting

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