Weak dipole moment of τ\tau in e+e−e^+e^- collisions with longitudinally polarized electrons

It is pointed out that certain CP-odd momentum correlations in the production and subsequent decay of tau pairs in $e^+e^-$ collisions get enhanced when the $e^-$ is longitudinally polarized. Analytic expressions for these correlations are obtained for the single-pion decay mode of $\tau$ when $\tau^+\tau^-$ have a ``weak" dipole form factor (WDFF) coupling to $Z$ . For $e^+e^-$ collisions at the $Z$ peak, a sensitivity of about 1-5$\times 10^{-17}$\mbox{$e$ cm} for the $\tau$ WDFF can be reached using a {\em single} $\tau^+\tau^-$ decay channel, with $10^6\, Z$'s likely to be available at the SLC at Stanford with $e^-$ polarization of 62\%-75\%.Comment: 9 pages, Latex, PRL-TH-93/17 (Revised

A trait‐based approach to plant species selection to increase functionality of farmland vegetative strips

Farmland vegetative strips are a proven source of support for ecosystem services and are globally used to mitigate effects of agricultural intensification. However, increasing pressures on agricultural land require increases in their functionality, such as supporting multiple ecosystem services concurrently. The plant species sown in a vegetative strip seed mix determine the establishment, plant community, and ecosystem services that are supported. Currently, there is no clearly defined or structured method to select plant species for multifunctional vegetative strips. Plant traits determine how plants support ecosystem services. Also, the establishment and persistence of plant communities is influenced by key internal and external factors. We propose a novel, evidence‐informed method of multifunctional vegetative strip design based on these essential traits and factors. This study had three distinct stages. The first identified plant traits that support water quality protection, pollinators and/or crop pest natural enemies, using existing research evidence. We then identified key factors affecting plant community establishment and persistence. Finally, we applied these standardized methods to design a multifunctional vegetative strip for a specific case study (UK lowland farmland). Key plant traits identified, included floral display size, flower color, nectar content, leaf surface area, leaf trichome density, percentage fine roots, root length, rooting depth, and root density. Key internal and external establishment factors included life history, native status, distribution, established competitive strategy, associated floristic diversity, flowering time and duration, and preferred soil type and pH. In the United Kingdom case study, we used five different plant traits and all of the identified factors to design a seed mix for a multifunctional vegetative strip. We present a transferable method of vegetative strip design that can be adapted for other ecosystem services and climates. It provides landowners and advisors with an evidence‐informed approach to increase field margin functionality while supporting farmland biodiversity

Analysis of averaged multichannel delay times

The physical significances and the pros and cons involved in the usage of different time delay formalisms are discussed. The delay time matrix introduced by Eisenbud, where only s-waves participate in a reaction, is in general related to the definition of an angular time delay which is shown not to be equivalent to the so-called phase time delay of Eisenbud and Wigner even for single channel scattering. Whereas the expression due to Smith which is derived from a time delayed radial wave packet is consistent with a lifetime matrix which is Hermitian, this is not true for any Eisenbud-type lifetime matrix which violates time reversal invariance. Extending the angular time delay of Nussenzveig to multiple channels, we show that if one performs an average over the directions and subtracts the forward angle contribution containing an interference of the incident and scattered waves, the multichannel angle dependent average time delay reduces to the one given by Smith. The present work also rectifies a recently misinterpreted misnomer of the relation due to Smith.Comment: 15 pages, LaTe

191. Biopsja węzła wartowniczego w operacyjnym raku gruczołu piersiowego – doświadczenia własne

Do chwili obecnej w przypadku raka piersi usunięcie układu chłonnego pachy jest obowiązkowym elementem postępowania chirurgicznego. Zajęcie węzłów chłonnych w przypadku raka piersi jest jednym z czynników rokowniczych jak i wpływa na podjęcie dalszego leczenia uzupełniającego i dlatego usunięcie pachowych węzłów chłonnych jest bardzo ważnym elementem leczenia operacyjnego raka piersi. Technika biopsji węzła wartowniczego (WW) rozwinęła się w przypadkach czerniaka złośliwego skóry i ma na celu precyzyjną ocenę stanu całego dorzecza węzłów chłonnych przy użyciu barwnika Paten Blau V, radioizotopu Tc99 ręcznej sóndy gamma kamery oraz małoinwazyjnej techniki chirurgicznej.Materiał i metodaW okresie od sierpnia 1998 roku do września 2003 roku w I Oddziale Chirurgii Onkologicznej Wielkopolskiego Centrum Onkologii w Poznaniu poddano biopsji WW 400 pacjentek z operacyjnym rakiem piersi. U wszystkich chorych klinicznie nie stwierdzano powiększonych węzłów chłonnych. Wiek pacjentek wahał się od 35 do 70 lat ze średnią wieku 55,2 lat. W przeddzień operacji podawano podskórnie w okolicę guza z czterech wkłuć Nannocoloid znaczony Tc99 w stężeniu 1 mCi zawarty w 4 mililitrach roztworu. Dnia następnego rano wykonywano limfoscyntygrafię celem wykonania mappingu węzła/węzłów wartowniczych. Następnie na sali operacyjnej podawano 1 do 2 mililitrów barwnika Patent Blau V w ten sam sposób, co radiokoloid. Przy użyciu ręcznej sondy gamma kamery identyfikowano miejsce największego wychwytu znacznika w pasze (tzw. Hot, Spot), które zaznaczano. Po odsłonięciu tkanki tłuszczowej pachy uwidaczniano wybarwione drogi chłonne, wzdłuż których dokonywano identyfikację wybarwionego węzła chłonnego. Następnie przy użyciu ręcznej sondy Navigator potwierdzano największy wychwyt promieniowania nad wybarwionym węzłem, w takim przypadku powyższy węzeł chłonny uważany był jako WW i przesyłany do pracowni patologicznej. Po identyfikacji WW chora poddawana była standardowej operacji (mastectomia lub BCT) wraz z limfadenektomią pachową jako nieodłącznym elementem procedury chirurgicznej.WynikiWW udało się zidentyfikować w 97% chorych. W przypadku 7 pacjentek nie udało się odnależć WW. Z pośród chorych z definiowanym WW przerzuty stwierdzono w 20% przypadków, w pozostałej części badanej grupy WW nie zawierał komórek nowotworowych, co stanowi 80% badanej populacji. W badanej grupie chorych stwierdzono 2 przypadki wyniku fałszywie ujemnego. W większoścr przypadków (87,1%) WW występował jako pojedynczy tylko u 2 pacjentów stwierdzono podwójny węzeł chłonny a u jednej chorej WW występował jako potrójny, ogółem mnogie WW wynosiły 2,88% populacji.WnioskiBiopsja WW jest bezpieczną metodą pozwalającą na ocenę dorzecza pachowych węzłów chłonnych w operacyjnym raku piersi. Wyniki nasze potwierdzają w pełni wyniki innych badaczy w Europie i na Świecie

Simple test for quantum channel capacity

Basing on states and channels isomorphism we point out that semidefinite programming can be used as a quick test for nonzero one-way quantum channel capacity. This can be achieved by search of symmetric extensions of states isomorphic to a given quantum channel. With this method we provide examples of quantum channels that can lead to high entanglement transmission but still have zero one-way capacity, in particular, regions of symmetric extendibility for isotropic states in arbitrary dimensions are presented. Further we derive {\it a new entanglement parameter} based on (normalised) relative entropy distance to the set of states that have symmetric extensions and show explicitly the symmetric extension of isotropic states being the nearest to singlets in the set of symmetrically extendible states. The suitable regularisation of the parameter provides a new upper bound on one-way distillable entanglement.Comment: 6 pages, no figures, RevTeX4. Signifficantly corrected version. Claim on continuity of channel capacities removed due to flaw in the corresponding proof. Changes and corrections performed in the part proposing a new upper bound on one-way distillable etanglement which happens to be not one-way entanglement monoton

Constraints on R-parity violating couplings from LEP/SLD hadronic observables

We analyze the one loop corrections to hadronic Z decays in an R-parity violating extension to the Minimal Supersymmetric Standard Model (MSSM). Performing a global fit to all the hadronic observables at the Z-peak, we obtain stringent constraints on the R-violating couplings constants lambda' and lambda''. As a result of the strong constraints from the b asymmetry parameters A_b and A_FB(b), we find that the couplings lambda'{i31}, lambda'{i32}, and lambda''{321} are ruled out at the 1 sigma level, and that lambda'{i33} and lambda''{33i} are ruled out at the 2 sigma level. We also obtain Bayesian confidence limits for the R-violating couplings.Comment: 30 pages, 19 postscript figures, REVTeX, new section 8 on Bayesian confidence limits adde

Charged Dual String Vacua from Interacting Rotating Black Holes Via Discrete and Nonlinear Symmetries

Using the stationary formulation of the toroidally compactified heterotic string theory in terms of a pair of matrix Ernst potentials we consider the four-dimensional truncation of this theory with no U(1) vector fields excited. Imposing one time-like Killing vector permits us to express the stationary effective action as a model in which gravity is coupled to a matrix Ernst potential which, under certain parametrization, allows us to interpret the matter sector of this theory as a double Ernst system. We generate a web of string vacua which are related to each other via a set of discrete symmetries of the effective action (some of them involve S-duality transformations and possess non-perturbative character). Some physical implications of these discrete symmetries are analyzed and we find that, in some particular cases, they relate rotating black holes coupled to a dilaton with no Kalb--Ramond field, static black holes with non-trivial dilaton and antisymmetric tensor fields, and rotating and static naked singularities. Further, by applying a nonlinear symmetry, namely, the so-called normalized Harrison transformation, on the seed field configurations corresponding to these neutral backgrounds, we recover the U(1)^n Abelian vector sector of the four-dimensional action of the heterotic string, charging in this way the double Ernst system which corresponds to each one of the neutral string vacua, i.e., the stationary and the static black holes and the naked singularities.Comment: 19 pages in latex, added referenc

QCD corrections to electroweak l nu_l jj and l^+ l^- jj production

The production of W or Z bosons in association with two jets is an important background to the Higgs boson search in vector-boson fusion at the LHC. The purely electroweak component of this background is dominated by vector-boson fusion, which exhibits kinematic distributions very similar to the Higgs boson signal. We consider the next-to-leading order QCD corrections to the electroweak production of l nu_l jj and l^+ l^- jj events at the LHC, within typical vector-boson fusion cuts. We show that the QCD corrections are modest, increasing the total cross sections by about 10%. Remaining scale uncertainties are below 2%. A fully-flexible next-to-leading order partonic Monte Carlo program allows to demonstrate these features for cross sections within typical vector-boson-fusion acceptance cuts. Modest corrections are also found for distributions.Comment: 26 pages, 10 figures. PRD final version. One reference corrected, introduction expande

On the bound states of the Dirac equation in the extreme Kerr metric

We study the eigenvalues of the angular equation arising after the separation of the Dirac equation in the extreme Kerr metric. To this purpose a self-adjoint holomorphic operator family associated to this eigenvalue problem is considered. We show that the eigenvalues satisfy a first order nonlinear differential equation with respect to the black hole mass and we solve it. Finally, we prove that there exist no bound states for the Dirac equation in the aforementioned metric.Comment: 13 page