We investigate the coefficients generated by expressing the falling factorial (xy) as a linear combination of falling factorial products xy for l, m = 1, . . . , k. Algebraic and combinatoric properties are discussed, some in relation to Stirling numbers.

با توجه به رشد بالای جمعیت در جهان و نیاز اطمینان از امنیت غذایی، افزایش تولید واحد سطح محصولات زراعی به‌منزلة راهبردی اساسی حل مسئلة تأمین غذا به‌شمار می‌رود. سوی دیگر، وجود محدودیت زیرکشت پایین‌بودن میانگین عملکرد برخی کشاورزی مانند گندم کشور، محصول می‌تواند راهکاری عملی پاسخ کشور محسوب شود. یکی مهم‌ترین بیماری‌های فوزاریوم است که، نقش پیش‌بینی این بیماری جلوگیری کاهش بهره‌وری محصول، مدل‌هایی...

We extend the geometric study of the Wasserstein space W2(X) of a simply connected, negatively curved metric space X by investigating which pairs of boundary points can be linked by a geodesic, when X is a tree. Let X be a Hadamard space, by which we mean that X is a complete globally CAT(0), locally compact metric space. Mainly, X is a space where triangles are “thin”: points on the opposite s...

Let P := k [X,Y, Z] be a polynomial ring over an algebraic closed field k and (X, Y , Z, XY Z, XY Z ) · k [X,Y, Z] an (X,Y, Z)-primary ideal in P , (m, n, l, a, b, c, d, e, f are integers). The ideal Q=(X, Y , Z, XY Z, XY Z ) ·R is (X,Y, Z) · R-primary ideal in the local ring R = k [X,Y, Z](x,y,z). In this short note we give a formula for the calculation of Samuel multiplicity e0(Q,R) of the id...

Three different models of MF1 strain mice were studied to measure the effects of gonadal secretions and sex chromosome type and number on body weight and composition, and on related metabolic variables such as glucose homeostasis, feeding, and activity. The 3 genetic models varied sex chromosome complement in different ways, as follows: 1) "four core genotypes" mice, comprising XX and XY gonada...

The randomly diluted resistor network and XY model at low temperature T are studied near the d-dimensional percolation threshold using the ɛ expansion, where ɛ=6-d. The series expansion of the inverse susceptibility in powers of T for the XY model is identical to that of the appropriate resistive inverse susceptibility in powers of σ0−1, where σ0 is the conductance of a bond. However, the tempe...

A rare form of the 46,XY disorders of sex development (DSD), 5a-reductase deficiency was first described in patients with pseudovaginal perineoscrotal hypospadias, microphallus, and cryptorchid testes in 1974 by Imperato. This undervirilization in the male is due to an alteration in the 5a-reductase type 2 gene (SRD5A2), which encodes for 5areductase activity. Our registry of 750 patients with ...

The Y chromosome from certain populations of M. m. domesticus is incapable of normal testis determination in the B6 inbred strain resulting in XY hermaphrodites or XY females (XY(DOM) sex reversal). B6 consomic strains have been developed with either transient (B6-Y(AKR)) or severe (B6-Y(TIR)) XY(DOM) sex reversal. We report that a point mutation, the dominant white spotting oncogene allele, Ki...

In Drosophila, the sex of germ cells is determined by cell-autonomous and inductive signals. XY germ cells autonomously enter spermatogenesis when developing in a female host. In contrast, XX germ cells non-autonomously become spermatogenic when developing in a male host. In first instar larvae with two X chromosomes, XX germ cells enter the female or the male pathway depending on the presence ...