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Coordinated changes of cellular plasticity and identity are critical for pluripotent reprogramming and oncogenic transformation. However, the sequences of events that orchestrate these intermingled modifications have never been comparatively dissected. Here, we deconvolute the cellular trajectories of reprogramming (via Oct4/Sox2/Klf4/c-Myc) and transformation (via Ras/c-Myc) at the single-cell resolution and reveal how the two processes intersect before they bifurcate. This approach led us to identify the transcription factor Bcl11b as a broad-range regulator of cell fate changes, as well as a pertinent marker to capture early cellular intermediates that emerge simultaneously during reprogramming and transformation. Multiomics characterization of these intermediates unveiled a c-Myc/Atoh8/Sfrp1 regulatory axis that constrains reprogramming, transformation and transdifferentiation. Mechanistically, we found that Atoh8 restrains cellular plasticity, independent of cellular identity, by binding a specific enhancer network. This study provides insights into the partitioned control of cellular plasticity and identity for both regenerative and cancer biology.

Since their discovery as pluripotent cytokines extractable from bone matrix, it has been speculated how bone morphogenetic proteins (BMPs) become released and activated from the extracellular matrix (ECM). In contrast to TGF-βs, most investigated BMPs are secreted as bioactive prodomain (PD)-growth factor (GF) complexes (CPLXs). Recently, we demonstrated that PD-dependent targeting of BMP-7 CPLXs to the extracellular fibrillin microfibril (FMF) components fibrillin-1 and -2 represents a BMP sequestration mechanism by rendering the GF latent. Understanding how BMPs become activated from ECM scaffolds such as FMF is crucial to elucidate pathomechanisms characterized by aberrant BMP activation and ECM destruction. Here, we describe a new MMP-dependent BMP-7 activation mechanism from ECM-targeted pools via specific PD degradation. Using Edman sequencing and mutagenesis, we identified a new and conserved MMP-13 cleavage site within the BMP-7 PD. A degradation screen with different BMP family PDs and representative MMP family members suggested utilization of the identified site in a general MMP-driven BMP activation mechanism. Furthermore, sandwich ELISA and solid phase cleavage studies in combination with bioactivity assays, single particle TEM, and in silico molecular docking experiments provided evidence that PD cleavage by MMP-13 leads to BMP-7 CPLX disintegration and bioactive GF release.

Coordinated changes of cellular identity and plasticity are critical for pluripotent reprogramming (PR) and malignant transformation (MT). However, the molecular circuitries orchestrating these modifications, as well as their degree of analogy during reprogramming and transformation, remain unknown. To address this question, we generated “repro-transformable” mice models and dissected comparatively the early events underpinning PR - mediated by Oct4, Sox2, Klf4, c-Myc - and MT - triggered by oncogenic Ras and c-Myc. Transcriptomic analyses allowed the identification of a unique set of markers - the cell surface glycoprotein Thy1 and the transcription factor (TF) Bcl11b - that are commonly downregulated during PR and MT and delineate cellular intermediates (CI) highly amenable to generate pluripotent or malignant derivatives. Comprehensive transcriptomic, epigenomic and functional analyses of different CI, prone or refractory to PR/MT, unveiled that cellular plasticity acquisition precedes the broad extinction of cellular identity. It also demonstrated the existence of specific and shared molecular features of PR and MT while ensuring the identification of broad-range regulators of cellular plasticity. As a proof-of-concept, we revealed that the basic helix-loop-helix (bHLH) class A TF Atoh8 constrains rodent and human iPS cells generation as well as MT and direct neuron conversion. Mechanistically, this TF hampers the reactivation of the pluripotent network during PR and limits the acquisition of phenotypic plasticity during MT. Furthermore, an integrated analysis of Atoh8 genome-wide binding, alongside the other bHLH TFs c-Myc, Ascl1 and MyoD promoting reprogramming/transdifferentiation, unveiled how Atoh8 constrains cellular plasticity by occupying a specific subset of MEF enhancers and by finetuning WNT signalling activity. Collectively, by deconvoluting the early steps of the reprogramming and transformation roadmaps, this integrated study uncoupled changes of cellular plasticity and identity to shed light on novel insights into reprogramming and cancer biology.Graphical abstractOne-sentence summaryComparative roadmaps of cellular plasticity acquisition during pluripotent reprogramming and malignant transformation.

RESUMO Atrazine é um herbicida recomendado para a cultura do milho, porém há poucas informações sobre seu efeito residual em hortaliças que eventualmente poderão ser cultivadas em sucessão. O objetivo dessa pesquisa foi avaliar a simulação do residual de subdoses de atrazine no substrato sobre o desenvolvimento e produção de cenoura 'Brasília'. Os tratamentos constituíram-se de oito doses decrescentes de atrazine (250, 25,0, 2,5, 0,25, 0,025, 0,0025, 0,00025 e 0 g i.a./ha) partindo da concentração de 1/10 da dose recomendada comercialmente para a cultura do milho doce (2500 g i.a./ha). O delineamento experimental foi inteiramente casualizado com quatro repetições. As unidades experimentais foram constituídas de vasos de plástico com capacidade de 20 L. As plantas de cenoura foram avaliadas quanto à porcentagem e índice de velocidade de emergência (aos 7, 14 e 21 dias após a aplicação), taxa de mortalidade, perímetro e comprimento de raiz, massa fresca de raiz e massa seca de parte aérea aos 29 e 90 dias após a aplicação (DAA). Concluiu-se que residual de até 250 g i.a/ha de atrazine pode causar redução na biomassa inicial da cenoura (29 DAA), sem, no entanto, prejudicar sua produção de raízes. ABSTRACT Atrazine is an herbicide recommended for the corn crop, but little information is available on its residual effect on vegetables that could be grown in succession. The objective of this research was to evaluate the residual simulation of atrazine doses in the substrate on the development and production of 'Brasília' carrot. Treatments consisted of eight decreasing doses of atrazine (250, 25.0, 2.5, 0.25, 0.025, 0.0025, 0.00025 and 0 g a.i./ha) starting on 1/10 of the concentration dose commercially recommended for sweet corn (2500 g a.i./ha). Experimental design was completely randomized with four replications. Experimental units consisted of plastic pots with a capacity of 20 L. The carrot plants were evaluated for percentage and emergence speed index (at 7, 14 and 21 days after application), mortality, length and perimeter of roots, root fresh weight and dry weight of aboveground part at 29 and 90 days after application (DAA). We concluded that residual up to 250 g a.i./ha atrazine might cause initial biomass reduction in carrot (29 DAA), without, however, damaging its production of roots.

Linear low density polyethylene (LLDPE) with different branching contents were prepared from ethylene, without the addition of α-olefin comonomer, using a combination of catalyst precursors {TpMs}NiCl (1) (TpMs = hydridotris(3-mesitylpyrazol-1-yl)) and Cp2ZrCl2 (2) activated with MAO/TMA (1:1) in toluene at 0 °C and by varying the nickel loading mole fraction (xNi). The polymerization results showed that the turnover frequencies are strongly dependent on the xNi varying from 6.6×103 to 32.1×103 mol[C2H4]/mol[Zr] h. The 13 C NMR spectra of the copolymers showed that the branch contents of the polymers increase as the xNi increase in the medium promoting the production of polymers with a wide range of melting point (Tm).

Objective: The objective of this study was to assess the results of completion pneumonectomy performed for non-small cell lung cancer, classified as second primary or recurrence/metastasis. Methods: From 1982 to 2000, 59 patients underwent completion pneumonectomy for lung cancer, classified second primary or recurrence/metastasis according to a modified form of Martini's criteria, after a mean interval from first resection of 60 months for second primary lung cancers and 19 months for recurrences/metastases. Results: Operative mortality was 3.4% and complications occurred in 30% of patients. Five-year survival rate for completely resected patients was 25% (median 20 months). No significant difference in long-term survival was detected between second primary and recurrent tumors; survival was not adversely affected by a resection interval of less than 2 years or less than 12 months. Conclusions: Completion pneumonectomy for non-small cell lung cancer is a safe surgical procedure in experienced hands; long-term survival is acceptable and the best results are obtained for stage I lung cancer. Distinction between second primary lung cancer and recurrence failed to demonstrate a prognostic value.

Branched polyethylene/high-density polyethylene blends (BPE/HDPE) were prepared using the combined [NiCl2(alpha-diimine)] (1) (alpha-diimine = 1,4-bis(2,6-diisopropylphenyl)-acenaphthenediimine) and [TpMs*VCl2(NtBu)] (2) (TpMs* = hydridobis(3-mesitylpyrazol-1-yl)(5-mesitylpyrazol-1-yl)) catalysts. The polymerization reactions were performed in hexane or toluene at three different polymerization temperatures (0, 30 and 50 °C) and several nickel molar fractions (xNi), using MAO as cocatalyst. At all temperatures, the activities show an approximate linear correlation with xNi, indicating a non-synergistic effect between the nickel and the vanadium species. Higher activities were found in toluene at 0 °C. The melting temperatures for the polyethylene blends produced at 0 °C decrease as xNi increases in the medium indicating good miscibility between the polyethylene phases made by both catalysts. The surface morphology of the BPE/HDPE blends studied by scanning electron microscopy (SEM) revealed low miscibility between the PE phases mainly in the case of the polymer blends produced at high temperature (50 ºC). Blendas de polietileno ramificado/polietileno de alta densidade (BPE/HDPE) foram preparadas usando uma combinação de catalisadores [NiCl2(diimina-alfa)] (1) (diimina-alfa = 1,4-bis(2,6-diisopropilfenila)-acenafeteno) e [TpMs*VCl2(NtBu)] (2) (TpMs* = hidridobis(3-mesitilapirazol-1-il)(5-mesitilapirazol-1-il)). As reações de polimerização foram realizadas em hexano ou tolueno em três diferentes temperaturas (0, 30 e 50 °C), utilizando várias razões molares de níquel (xNi), na presença de metilaluminoxano (MAO) como cocatalisador. Em todas as temperaturas, as atividades mostraram uma correlação aproximadamente linear com xNi, indicando o não aparecimento de um efeito sinérgico entre as espécies de níquel e vanádio. Altas atividades foram obtidas a 0 °C. As temperaturas de fusão (Tm) das blendas de polietileno produzidas a 0 °C diminuem conforme a xNi aumenta no meio reacional, indicando uma boa miscibilidade entre as fases de polietileno produzidas por ambos catalisadores. A morfologia da superfície das blendas de BPE/HDPE estudadas por microscopia eletrônica de varredura (MEV) revelou uma baixa miscibilidade entre as fases de PE, principalmente no caso das blendas poliméricas produzidas a alta temperatura (50 ºC).

Objective: To assess operative mortality (OM), morbidity and long-term results of sleeve lobectomies performed for non-small cell lung cancer (NSCLC) and carcinoids during a 35-year period. Methods: A retrospective review of patients who underwent a sleeve lobectomy for NSCLC and carcinoids was undertaken, univariate and multivariate analyses of factors influencing early mortality in NSCLC were performed and for this purpose the series was split into an early and a contemporary phase, the Kaplan‐Meier method was used to calculate the cumulative survival rate, and statistical significance was calculated with the log‐rank test. Causes of death were evaluated in relation to the stage of the disease. Results: OM for NSCLC was 14.6% in the early phase and 6% in the contemporary one; late stenosis occurred in 7.7% of NSCLC patients in the early phase and in 2% in the contemporary one. No OM or late stenosis occurred in carcinoid patients. Three, 5 and 10-year survival rates excluding carcinoids were 77, 62 and 31% for stage I(A‐B), 45, 34 and 27% for stage II(A‐B), 33, 22 and 0% for stage III(A‐B). The 10-year survival rate for carcinoids was 100%. There was no significant difference in long-term survival between stages II and III, while the difference between stage I and stages II and III was significant ðP , 0:001Þ: When survival was analyzed in relation to nodal status, 3, 5 and 10year survival rates were 71, 57 and 33% for N0 disease, 42, 33 and 22% for N1 disease, and 34 and 19% with the last observation at 82 months of 19% for N2 disease; there was no significant difference in survival between N1 and N2 disease. A second primary lung cancer occurred in six patients (3.7%) who underwent resection. Late mortality was not related to cancer in most stage I patients while in stages II and III patients it was related to local and distant recurrences. Conclusions: Sleeve lobectomy is a valid alternative to pneumonectomy: careful patient selection and surgical technique make it possible to achieve a mortality rate comparable to or lower than that for pneumonectomy along with a better quality of life. In addition, it allows further lung resection, if necessary. q 2002 Elsevier Science B.V. All rights reserved.

In this paper a new supersymmetric extension of conformal mechanics is put forward. The beauty of this extension is that all variables have a clear geometrical meaning and the super-Hamiltonian turns out to be the Lie-derivative of the Hamiltonian flow of standard conformal mechanics. In this paper we also provide a supersymmetric extension of the other conformal generators of the theory and find their "square-roots". The whole superalgebra of these charges is then analyzed in details. We conclude the paper by showing that, using superfields, a constraint can be built which provides the exact solution of the system., 11 pages, no figures

This work aimed to evaluate the Deladenus siricidicola, Bedding (Neotylenchidae)parasitism in adults Sirex noctilio, Fabricius, 1793 (Hymenoptera: Siricidae). Timber was sampled by cutting out pieces of 0.80 m in length in Sirex noctilio attacked and Deladenus siricidicola inoculated Pinus taeda. Longs were 15-20 cm in diameter, according to the tree age. Samples were packed in gauze-cages, for daily observations, till S. noctilio adults emergence. The emerged insects were transported, in plastic containers to the laboratory, where they were sectioned and dissected under stereoscopic microscopy to observ the nematode occurrence. From the initially proposed ten units, nine of them were evaluated in a total of 1,810 emerged adult insects, being 1,441 males and 369 females. Nematode parasitism was shown in 267 males and 74 females, in a total of 341 infected insects (18.84%). O objetivo do presente trabalho foi avaliar o parasitismo do nematóide Deladenus siricidicola,Bedding (Neotylenchidae)em adultos de Sirex noctilio, Fabricius, 1793 (Hymenoptera: Siricidae). Foram utilizados toretes de 0,80 cm de comprimento, retirados do terço médio de árvores de Pinus taeda atacadas por Sirex noctilio e inoculadas com Deladenus siricidicola. Os toretes possuíam diâmetro entre 15-20 cm, de acordo com a idade das árvores. As amostras foram acondicionadas em gaiolas ou tonéis vedados com tela de nylon e seguros por cintas de borracha, permanecendo em observação diária até a emergência dos insetos adultos. Os insetos foram trasportados em recipientes plásticos para o laboratório, onde foram seccionados e dissecados sob microscópio estereoscópico, para a verificação da ocorrência ou não do nematóide. Foram avaliadas nove das dez unidades inicialmente propostas. Nestas, foram analisados 1.810 insetos adultos, sendo 1.441 machos e 369 fêmeas. O parasitismo pelo nematóide foi verificado em 267 machos e 74 fêmeas, em um total de 341 insetos parasitados, com uma porcentagem de parasitismo de 18,84%.

In this paper we propose a new supersymmetric extension of conformal mechanics. The Grassmannian variables that we introduce are the basis of the forms and of the vector-fields built over the symplectic space of the original system. Our supersymmetric Hamiltonian itself turns out to have a clear geometrical meaning being the Lie-derivative of the Hamiltonian flow of conformal mechanics. Using superfields we derive a constraint which gives the exact solution of the supersymmetric system in a way analogous to the constraint in configuration space which solved the original non-supersymmetric model. Besides the supersymmetric extension of the original Hamiltonian, we also provide the extension of the other conformal generators present in the original system. These extensions have also a supersymmetric character being the square of some Grassmannian charge. We build the whole superalgebra of these charges and analyze their closure. The representation of the even part of this superalgebra on the odd part turns out to be integer and not spinorial in character., Comment: Superfield re-defined

Vancomycin penetration into lung tissue was evaluated in thirty patients following the administration of 1 g of vancomycin as a 1 h i.v. infusion. Mean concentrations (range) of vancomycin in lung tissue were 9.6 (6.3-12.1) mg/kg at 1h, 5.7 (4.7-7.4) mg/kg at 2 h, 4.2 (0.8-6.5) mg/kg at 3-4 h, 2.4 (1.4-4.7) mg/kg at 6 h, and 2.8 (0.9-7.8) mg/kg at 12 h after the end of infusion. Ratios of lung tissue to serum concentration ranged 0.24 to 0.41 at 1 and 12 h, respectively. One of six patients observed at 6 h, and 3 of 7 patients at 12 h did not have detectable levels of vancomycin in lung tissue. A 1 h iv infusion of a 1 g dose of vancomycin does not achieve sustained lung concentrations above the MIC for susceptible staphylococci over a dosing interval of 12 h. Therefore, a more appropriate modality of administration, such as continuous infusion, should be considered.

We investigate supersymmetric quantum mechanics in curved space. In particular we discuss, in the framework of the canonical formulation, the role of supersymmetry (SUSY) and of invariance under general coordinate transformations (GCT) in solving the operator ordering ambiguity. It is shown that GCT invariance is instrumental to achieve such result. We also examine the connection with the Weyl ordering of operators and the relevance of our results for the path integral approach.

A new class of multimeron solutions is obtained in the framework of a generally invariant gauge theory.

A new formulation of the euclidean functional approach to quantum field theory is proposed. It is based on functional integration over a Gibbs ensemble. This automatically ensures invariance with respect to general field transformations. The new momenta conjugate to the field variables perform naturally the role of the ghost fields required by the general consistency of the theory.

We show that the combined use of N=1 supersymmetry and general coordinate invariance allows to completely fix the operator ordering ambiguity for a non-relativistic interacting spinning particle.

We discuss some consequences of applying a procedure developed in a previous paper, to implement the conformal and general invariance of the functional integral. It is shown that spontaneous breaking of those symmetries is unavoidable; we consider in particular the linear σ-model, in the conformal limit, and the Einstein gravitation and derive some simple relations among the vacuum expectation value, a phenomenological cut-off and the Lagrangian constants.

This paper describes a functional formulation of Euclidean quantum field theory, based on a complete equivalence with classical statistical mechanics. One introduces an extra time variable and sets up a canonical scheme with new Lagrangian and Hamiltonian functions. The generating functional is then defined as the Gibbs average over the ensemble. This allows us, in particular, to control in a simple way the invariance properties of the integration measure. In several cases of physical interest it is seen that the invariance requirement leads to extra determinantal factors in the integration volume and, therefore, to a set of improved Feynman rules. In particular, enforcing dilatation invariance for the generating functional is shown to lead to a nonzero background,i.e. to spontaneous breaking of the symmetry. The application of the method to constrained systems is discussed in detail and in the case of Yang-Mills theories the Faddeev-Popov prescription for quantization is reproduced with remarkable simplicity. A discussion of the functional quantization of gravity is also offered.

In this paper it is shown how to get, through the use of suitable commutation relations, sum rules for the renormalization ratios between bare and dressed coupling constants. The method is completely general and it can be applied to any broken symmetry. As an illustration we have considered the cases of the weak vector current, both strangeness-conserving and strangeness-changing.

The properties of the bound-state solutions of the BetheSalpeter equation in the ladder approximation are investigated in the case of potentials strongly singular at the origin. The analogy with potential scattering and the connexion to field theory are discussed. A method is given which allows the reduction of the singular problem to a regular one and explicit solutions for eigenvalue and eigenfunctions are presented in a particular case.

We consider different examples of field theories, superrenormalizable, renormalizable and nonrenormalizable ones, in order to evaluate the renormalization constantZ of the vertex between a bound state and the component particles. In ladder approximation, some properties of theZ’s are examined, with particular regard to the possibility of the cut-off factorization.

Some characteristic features of the scattering by singular potentials are investigated both in the low- and the high-energy limit.

It is shown that the derivation of the standard sum rules requires more than the null plane structure of the commutators. The usual form is obtained only for a definite smooth behaviour of the current commutator near the light cone, which corresponds to the hypothesis of superconvergence for strong and and semistrong amplitudes.

The total cross section to e/sup 6/ is calculated for annihilation of an electron-positron pair into photons. Comparison with experiments at CERN is discussed and some consideration about the behavior of cross section for electrodynamical processes at high energy is outlined. Some details of calculation are sketched in an appendix. (auth)

We study classical solutions of the meron type in the framework of N = 3 and N = 4 extended supergravity.

We offer a systematic treatment of the connection between stochastic quantization and supersymmetry. This is done in the original Nicolai-Parisi-Sourlas approach and by use of the “stochastic identities” which can be derived as a consequence of the supersymmetry invariance both of the action and of the vacuum. We deal extensively with the cases of quantum mechanics, scalar field theory and gauge theory. One of the main results is the presence of a reduced set of stochastic identities even when a local Nicolai transformation does not exist.

The properties of a field theory in one over-all time dimension, invariant under the full conformal group, are studied in detail. A compact operator, which is not the Hamiltonian, is diagonalized and used to solve the problem of motion, providing a discrete spectrum and normalizable eigenstates. The role of the physical parameters present in the model is discussed, mainly in connection with a semi-classical approximation.

The correspondence between stochastic quantization and supersymmetry is extended to N =1 gauge supersymmetry coupled with matter. This applies to N =2 extended gauge supersymmetry and also to N =1 SUSY in six dimensions. The special role of the light plane gauge is emphasized.

A case of primary ependymoma of the mediastinum is reported. The tumor was adherent to the lung and metastasized to adjacent mediastinal lymph nodes. An autopsy showed no evidence of tumor in the central nervous system. The diagnosis of ependymoma was confirmed by the immunohistochemical positivity for glialfibrillary acidic protein. To the best of our knowledge, this is the first reported example of an ependymoma in this location.

The correspondence between stochastic quantization and supersymmetry is reobtained for the quantum mechanics case by use of “stochastic identities”. The method is easily generalized to N =1 super Yang-Mills theory in the light cone gauge.

We present a preliminary discussion of some consequences of a fully dilatational invariant formulation of the Einstein theory of gravitation. Arguments are given to show that the small distance behaviour of the theory can be greatly improved, leading to a situation very similar to usual renormalizable theories.

The authors discuss in detail the classical solutions of two field theoretical models invariant under general variable transformations. In particular they examine the case of a Yang-Mills theory and of a four-dimensional nonlinear sigma model, both coupled to 'strong gravitation'. Instanton, meron and multimeron configurations are obtained and their properties discussed. (25 refs).

We discuss the role of the Newton constant in gravity theory. We show that the natural way to deal with the general covariance of the theory is to notice that the action is independent of any dimensional constant. The Newton constant is introduced in gravity through the classical constant solutionγμν=(1/l2)δμν which displays the dilatation breaking of this Poincare invariant solution. Nothing changes for the usual results of classical gravity since the Newton constant is responsible for the low-energy limit. However, it is easy to realize that there are other solutions of gravity coupled to matter (Yang-Mills and sigma-model) where both fields have the same intensity and the Newton constant does not appear. These «non-Newtonian» solutions are due to the specific nonlinear character of general gravitation. They can be relevant to the hadron structure. The above observations give a hint that the asymptotically small-distance behaviour of the gravity theory is independent of Newton's constant and should reflect the general invariance of the theory, provided that infinite classes of quantum diagrams are summed up.

In the last two decades improvements in immunosuppression, surgical technique and graft preservation has impressively enhanced transplantation late results. In the present paper we wonder whether this surgical procedure has a role in the treatment of patients with end-stage respiratory disease as cystic fibrosis (CF). We also try to relate on the main clinical, histological development, present status and the real therapeutic value of cardiopulmonary and double-lung transplantation for end-stage CF. We believe lung transplant may well extend the patient life and give a better quality of life to CF patients who would otherwise die, although functional time is presently unknown. Next years challenge ought to be to go critically through clinical results, to focus on existing problems, together with developing appropriate solutions so to allow a better surgical indication of pulmonary transplantation.

We discuss, both in potential scattering and in quantum field theory, the connection between the bound state problem and the renormalizability of the theory. In particular, it is shown that a meaning can be given to the bound-state condition also in the framework of perturbation theory, also if all the terms of the series are cut-off-dependent.

We study the solutions of the Bethe-Salpeter equation for bound states, in the ladder approximation, in the case of potentials both regular and singular near the origin. Two methods are presented, one in momentum space, the other in co-ordinate space, which allow the complete determination of eigenvalues and eigenfunctions, in the case where both the total energyE of the state and the mass of the exchanged particle are zero.

A new relativistic approach to the problem of broken symmetries is proposed. This is the covariant generalization of the non-relativistic sum rules obtained in previous investigations. The result is in the form of dispersion sum rules where the pole term represents the group-theoretical answer and the cut the breaking correction. The method is applied toSU3 and chiralSU3×SU3 leading to very satisfactory results and predictions.

We study the short-wavelength approximation to the Schrodinger equation in the presence of one and two turning points. Two methods are presented which allow the evaluation of the higher corrections to the elementary W.K.B. approximation. The first method, the « real method », employs higher transcendental functions, the second one uses complex integration techniques.

A general method for calculating the renormalization of partially conserved vector currents due to symmetry breaking is discussed. As an application, the renormalization of the strangeness-changing weak vector current is calculated in the pole approximation and its effect on universality is discussed.

The validity of the renormalization group equations used to obtain Regge pole behavior is discussed. It is shown that the renormalization group equations contain a certain amount of arbitrariness when a perturbation theory amplitude is used as input. (C.E.S.)