Search

We study the decay of the $Z$ vector boson into a photon and a massless (invisible) dark photon in high-energy collisions. The photon can be used as trigger for the event, while the dark photon is detected indirectly as missing momentum in the event final state. We investigate the possibility of searching for such a dark photon at the LHC, HL-LHC and future lepton colliders, and compare the respective sensitivities. As expected, the best result is found for the lepton colliders running at the $Z$ mass, FCC-ee and CEPC, with a final sensitivity to branching ratios of order $O(10^{-11})$. We also discuss how to use the photon angular distribution of the events in lepton collisions to discriminate between the dark photon and a pseudo-scalar state like the axion., 12 pages, 8 figures, G. Panizzo corresponding author

To evaluate the local control (LC) and long term adverse effects in a series of patients with lung metastases who received 30 Gy in single dose with stereotactic technique.Between December 2008 and April 2016, a total of 166 lung metastases in 129 patients affected by oligometastatic disease were treated at our Institution with stereotactic body radiotherapy (SBRT). Mainly, the primary tumors were non small-cell lung cancer and colorectal cancer (45.2% and 28.8%, respectively). Prognostic factors were also assessed.The median follow-up was 38 months. Local progression occurred in 24 (14.4%) lesions in 21 patients. Intra-thoracic progression (new lung lesions or thoracic lymph node metastases) occurred in 59 (45.7%) patients. Forty-five (34.8%) patients had distant progression after a median time of 14 months. The 3- and 5-years local relapse-free survival (LPFS) were 80.1% and 79.2% (median not reached), respectively. One-hundred forty-eight patients were evaluated for late toxicity (follow-up6 months): 51 (34.4%) patients had grade ≤2 fibrosis, 11 (7.4%) patients experienced grade 3 fibrosis. Two (1.3%) cases of rib fracture occurred. One case of toxic death (grade 5) has been reported. Median OS was 39 months. At the univariate analysis, lesion diameter ≤18 mm correlated significantly with a longer LPFS (p = 0.001). At the multivariate analysis, lesion diameter18 mm was predictive for longer LPFS (p = 0.006). Also, oligometastases from primary colorectal cancer was a significant predictive factor for worse LPFS (p = 0.041) and progression-free survival (p = 0.04).To our knowledge, the current study represents the largest series on the use of SBRT 30 Gy single dose for lung metastases. Our results confirm the effectiveness and safety of this schedule administered in selected oligometastatic patients. Further prospective series could better validate these results.

Use anti-angiogenic strategies to prevent intraplaque angiogenesis studying the effects of the inhibition of bFGF (using K5) and PFKFB3 (using AZ33) on plaque angiogenesis.

In search for a microscopic description of ``droplet-like'' properties for the Ising spin glass (single component order parameter, zero modes i.e. correlation functions vanishing at infinity) we reconsider the two-packet model of Bray and Moore, which is effectively Replica-Symmetric and enjoys zero modes but only up to one-loop. We show how an appropriate change in the limits of the basic parameters of the model (packet size and replica number) allows for a derivation of Ward-Takahashi (WT) identities, thus ensuring the existence of zero modes to all orders and opening the way for a Lagrangean formulation of a ``droplet-like'' field theory for the Ising spin glass., Comment: latex WTDropletSpinGlass-unix.tex, 1 file, 9 pages (v2 for cosmetic corrections suggested by referees) [http://www-spht.cea.fr/articles/T05/132]

Our study aimed at a retrospective evaluation of clinicAL/biochemical progression in prostate cancer patients treated with intermittent androgenic deprivation (IAD) after a period of continuous cut off (CAD). Methods From 1996 to 2003 40 patients have been screened. 8 (gr.A) with increased PSA after radical prostatectomy (pT2N0M0); 32 (gr.B) had no surgical treatment due to age or other pathologies (Gleason ≤ 8). Patients have been monitored dosing out PSA every 3 months. CAD has been applied for an average period of 40 ± 10 months (med. 36). IAD has been performed by an “off” stage of interruption, alternately with an “on” stage of treatment. The cut-off for the suspension/resumption of therapy has been 0.4 ng/mL of PSA for group A and 3 ng/mL for group B. All patients have been received at least 3 cycles of therapy, each including “on” and “off” stages. Results After an average follow-up of 48 ± 12 months (med. 42) since the beginning of IAD, the progression-free survival has been 100% for group A and 96.8% for group B. The intermediate time of stage “off” during IAD pointed out a progression increment from the first cycle (51.6% gr. A, 46.6% gr. B) to the third cycle (73.5% gr. A, 76% gr. B). Conclusions The study pointed out that the actual average time of pharmacological treatment has been 47% for the period CAD+IAD and 31.5% for IAD only, keeping the PSA always near the nadir. Besides keeping the progression close to 0, we obtained an appreciable saving on the pharmacological costs and an improvement in the quality of life of patients due to the regression of the side-effects of therapy during stage “off”. Nevertheless it is still controversial in the Litterature on the pharmacological procedure to adopt, on the more suitable values of cut-off in PSA and on the timing of monitoring of patients.

We show that there is no need to modify the Parisi replica symmetry breaking ansatz, by working with R steps of breaking and solving exactly the discrete stationarity equations generated by the standard 'truncated Hamiltonian' of spin glass theory.

Bladder carcinoma with transitional cells is the most frequent neoplasia in the urinary system, but it is quite rare in patients under 40 years of age (0.4–2%). An analysis of 21 patients under 40 and a review of other reports show that tumors in patients under 20 years old have little tendency to recur and to progress, while tumors in patients aged between 21 and 40 have a behavior pattern similar to older age groups regarding recurrence and disease progression. Preliminary results of a study using fluorescent in situ hybridization with probes for the centromere of chromosomes 7 and 17 showed a high incidence of aneusomy with regard to these chromosomes and a genetic difference between superficial tumors in the young and in adults. Using probes from chromosomes already described in bladder carcinogenesis, we obtained higher sensitivity and specificity in detecting aneuploid events.

The serous papillary cystadenocarcinoma is a rare testicular neoplasm, which depending on the histological features can behave more or less aggressive, thus leading to a not always predictable prognosis. We present diagnosis and treatment of a case of serous papillary cystadenocarcinoma of the testis with associated adherent mass to the tunica albuginea, which compressed the parenchyma without infiltrating it.

Some recent results concerning the Sherrington-Kirkpatrick model are reported. For $T$ near the critical temperature $T_c$, the replica free energy of the Sherrington-Kirkpatrick model is taken as the starting point of an expansion in powers of $\delta Q_{ab} = (Q_{ab} - Q_{ab}^{\rm RS})$ about the Replica Symmetric solution $Q_{ab}^{\rm RS}$. The expansion is kept up to 4-th order in $\delta{\bm Q}$ where a Parisi solution $Q_{ab} = Q(x)$ emerges, but only if one remains close enough to $T_c$. For $T$ near zero we show how to separate contributions from $x\ll T\ll 1$ where the Hessian maintains the standard structure of Parisi Replica Symmetry Breaking with bands of eigenvalues bounded below by zero modes. For $T\ll x \leq 1$ the bands collapse and only two eigenvalues, a null one and a positive one, are found. In this region the solution stands in what can be called a {\sl droplet-like} regime., Comment: 11 pages, 3 figures, Published version

The problem of diagonalizing a class of complicated matrices, to be called ultrametric matrices, is investigated. These matrices appear at various stages in the description of disordered systems with many equilibrium phases by the technique of replica symmetry breaking. The residual symmetry, remaining after the breaking of permutation symmetry between replicas, allows us to bring all ultrametric matrices to a block diagonal form by a common similarity transformation. A large number of these blocks are, in fact, of size 1 times 1, i.e. in a vast sector the transformation actually diagonalizes the matrix. In the other sectors we end up with blocks of size (R+1) times (R+1) where R is the number of replica symmetry breaking steps. These blocks cannot be further reduced without giving more information, in addition to ultrametric symmetry, about the matrix. Similar results for the inverse of a generic ultrametric matrix are also derived., Comment: Title page + 30 pages, Plain Tex using \epsf for 7 figures, ITP. Budapest-Report No.506

A complex problem is solved here; we show how to write Dyson's equations for the (Ising) spin-glass that relate the propagator G to the mass operator M. In other words we are able to reduce the inversion of an ultrametric matrix M to the solution of a Dyson's equation in all sectors (for the replicon sector the result had already been derived). It turns out that what renders the problem tractable is using, instead of the components of G (or M), an object called here the “kernel" from which one can deduce the components themselves after dressing it with ultrametric weights and summing over eigenvalue indices with their appropriate multiplicity. Dyson's equations are then established as stationarity equations of tr In M - tr GM, where the kinetic terms are incorporated in M. At each stage we illustrate the calculation by providing explicit answers for the bare system (meau field in M). In particular the introduction of the “kernel" allows us to construct the bare propagator for a Lagrangean where one retains all quartic invariants. The case of the system in a magnetic field is also treated.

To test the stability of the Parisi solution near T=0, we study the spectrum of the Hessian of the Sherrington-Kirkpatrick model near T=0, whose eigenvalues are the masses of the bare propagators in the expansion around the mean-field solution. In the limit $T\ll 1$ two regions can be identified. In the first region, for $x$ close to 0, where $x$ is the Parisi replica symmetry breaking scheme parameter, the spectrum of the Hessian is not trivial and maintains the structure of the full replica symmetry breaking state found at higher temperatures. In the second region $T\ll x \leq 1$ as $T\to 0$, the components of the Hessian become insensitive to changes of the overlaps and the bands typical of the full replica symmetry breaking state collapse. In this region only two eigenvalues are found: a null one and a positive one, ensuring stability for $T\ll 1$. In the limit $T\to 0$ the width of the first region shrinks to zero and only the positive and null eigenvalues survive. As byproduct we enlighten the close analogy between the static Parisi replica symmetry breaking scheme and the multiple time-scales approach of dynamics, and compute the static susceptibility showing that it equals the static limit of the dynamic susceptibility computed via the modified fluctuation dissipation theorem., Comment: 24 pages, 6 figures, J. Phys. A (in press)

A loop expansion around Parisi's replica symmetry breaking mean field theory is constructed, in zero field. We obtain the equation of state (and associated Parisi's solution) below the upper critical dimension du=6, and, in particular, explicit corrections in εlnt and (εlnt)2 with t=(Tc−T)/Tc and ε=6−d. This allows us to verify that standard scaling is satisfied with β=1+ε/2+0(ε2). We have also investigated the transverse (replicon) correlation function, particularly at zero overlap. Near du, G00 (p) ~ t/P4 (for p~0) is the most obvious obstacle to a meaningful theory in d=3. If we make the twofold assumption that (i) scaling applies, and (ii) the replicon propagator is dominated by the spectrum of the (small) transverse masses, we obtain the softer behavior G00(p) ~ (1/p2–η). (t/p1/v)β and a prediction for a soft replicon spectrum in tγk2γ/β γ/β instead of tk2 at du. We have checked tγ to one loop and work is in progress to check k2γ/β to the same order. Taking the above divergence in p−(d+2−η)/2 as the leading divergence defines the lower critical dimension d ℓ by d ℓ=2−η (d ℓ). Known values of η (at d=6, from the ε expansion at Tc, or from numerical work at d=4, 3) are compatible with d ℓ ~ 2.5±.3.

An expansion for the free energy functional of the Sherrington-Kirkpatrick (SK) model, around the Replica Symmetric SK solution $Q^{({\rm RS})}_{ab} = \delta_{ab} + q(1-\delta_{ab})$ is investigated. In particular, when the expansion is truncated to fourth order in. $Q_{ab} - Q^{({\rm RS})}_{ab}$. The Full Replica Symmetry Broken (FRSB) solution is explicitly found but it turns out to exist only in the range of temperature $0.549...\leq T\leq T_c=1$, not including T=0. On the other hand an expansion around the paramagnetic solution $Q^{({\rm PM})}_{ab} = \delta_{ab}$ up to fourth order yields a FRSB solution that exists in a limited temperature range $0.915...\leq T \leq T_c=1$., Comment: 18 pages, 3 figures

We study the spectrum of the Hessian of the Sherrington-Kirkpatrick model near T=0, whose eigenvalues are the masses of the bare propagators in the expansion around the mean-field solution. In the limit $T\ll 1$ two regions can be identified. The first for $x$ close to 0, where $x$ is the Parisi replica symmetry breaking scheme parameter. In this region the spectrum of the Hessian is not trivial, and maintains the structure of the full replica symmetry breaking state found at higher temperatures. In the second region $T\ll x \leq 1$ as $T\to 0$, the bands typical of the full replica symmetry breaking state collapse and only two eigenvalues are found: a null one and a positive one. We argue that this region has a droplet-like behavior. In the limit $T\to 0$ the width of the full replica symmetry breaking region shrinks to zero and only the droplet-like scenario survives., 5 pages, 1 figure, EPL in press

The spin glass behavior near zero temperature is a complicated matter. To get an easier access to the spin glass order parameter $Q(x)$ and, at the same time, keep track of $Q_{ab}$, its matrix aspect, and hence of the Hessian controlling stability, we investigate an expansion of the replicated free energy functional around its ``spherical'' approximation. This expansion is obtained by introducing a constraint-field and a (double) Legendre Transform expressed in terms of spin correlators and constraint-field correlators. The spherical approximation has the spin fluctuations treated with a global constraint and the expansion of the Legendre Transformed functional brings them closer and closer to the Ising local constraint. In this paper we examine the first contribution of the systematic corrections to the spherical starting point., 16 pages, 2 figures

The expansion of the order parameter q(x) of an Ising spin glass in the inverse number 1/z of interacting neighbours, corresponding to the standard field theoretic loop expansion, is considered above d=6 in the vicinity of the critical temperature. Replica symmetry-breaking effects are found not only to be stable but even enhanced by fluctuations as d decreases. It is argued that higher-loop corrections cannot modify the exponents predicted by this effective mean-field theory.

A supersymmetric formalism is used to derive a set of equations giving the density of states of any real, symmetric, sparse random matrix as a function of the distribution of non-zero elements and the mean number of non-zero elements per row, p. In the matrix where the non-zero elements take the values +or-1 with equal probability the equations are solved as p to infinity recovering results obtained previously with the replica method. As E to 0 the density of states rho (E) behaves as 1/E(ln(E))2. The more general case where +or-1 occur with unequal probabilities is also considered.

Strong infrared divergences prevent standard spin glass field theory to be meaningful, at least below d = 6. A mechanism that softens infrared divergences is displayed, that, via the existence of a sea of zero or near zero modes, relates softening in infrared divergences and in the small x behavior of Parisi order parameter q(x). This mechanism may, hopefully, allow the building of a meaningful spin glass field theory in the condensed phase.

We study the transition of short range Ising spin glasses in a magnetic field, within a general replica symmetric field theory, which contains three masses and eight cubic couplings, that is defined in terms of the fields representing the replicon, anomalous and longitudinal modes. We discuss the symmetry of the theory in the limit of replica number n to 0, and consider the regular case where the longitudinal and anomalous masses remain degenerate. The spin glass transitions in zero and non-zero field are analyzed in a common framework. The mean field treatment shows the usual results, that is a transition in zero field, where all the modes become critical, and a transition in non-zero field, at the de Almeida-Thouless (AT) line, with only the replicon mode critical. Renormalization group methods are used to study the critical behavior, to order epsilon = 6-d. In the general theory we find a stable fixed-point associated to the spin glass transition in zero field. This fixed-point becomes unstable in the presence of a small magnetic field, and we calculate crossover exponents, which we relate to zero-field critical exponents. In a finite magnetic field, we find no physical stable fixed-point to describe the AT transition, in agreement with previous results of other authors., 36 pages with 4 tables. To be published in Phys. Rev. B

The field theory of a short range spin glass with Gaussian random interactions, is considered near the upper critical dimension six. In the glassy phase, replica symmetry breaking is accompanied with massless Goldstone modes, generated by the breaking of reparametrization invariance of a Parisi type solution. Twisted boundary conditions are thus imposed at two opposite ends of the system in order to study the size dependence of the twist free energy. A loop-expansion is performed to first order around a twisted background. It is found, as expected but it is non trivial, that the theory does renormalize around such backgrounds, as well as for the bulk. However two main differences appear, in comparison with simple ferromagnetic transitions : (i) the loop expansion yields a (negative) anomaly in the size dependence of the free energy, thereby lifting the lower critical dimension to a value greater than two given by $d_c = 2-\eta(d_c)$ (ii) the free energy is lowered by twisting the boundary conditions. This sign may reflect a spontaneous spatial non-uniformity of the order parameter., Comment: 15 pages, latex, no figure

We use the generic replica symmetric cubic field-theory to study the transition of short range Ising spin glasses in a magnetic field around the upper critical dimension, d=6. A novel fixed-point is found, in addition to the well-known zero magnetic field fixed-point, from the application of the renormalization group. In the spin glass limit, n going to 0, this fixed-point governs the critical behaviour of a class of systems characterised by a single cubic interaction parameter. For this universality class, the spin glass susceptibility diverges at criticality, whereas the longitudinal mode remains massive. The third mode, the so-called anomalous one, however, behaves unusually, having a jump at criticality. The physical consequences of this unusual behaviour are discussed, and a comparison with the conventional de Almeida-Thouless scenario presented., Comment: 5 pages written in revtex4. Accepted for publication in Phys. Rev. Lett

Symmetry considerations and a direct, Hubbard-Stratonovich type, derivation are used to construct a replica field-theory relevant to the study of the spin glass transition of short range models in a magnetic field. A mean-field treatment reveals that two different types of transitions exist, whenever the replica number n is kept larger than zero. The Sherrington-Kirkpatrick critical point in zero magnetic field between the paramagnet and replica magnet (a replica symmetric phase with a nonzero spin glass order parameter) separates from the de Almeida-Thouless line, along which replica symmetry breaking occurs. We argue that for studying the de Almeida-Thouless transition around the upper critical dimension d=6, it is necessary to use the generic cubic model with all the three bare masses and eight cubic couplings. The critical role n may play is also emphasized. To make perturbative calculations feasible, a new representation of the cubic interaction is introduced. To illustrate the method, we compute the masses in one-loop order. Some technical details and a list of vertex rules are presented to help future renormalisation-group calculations., Comment: 25 pages. Latex2e with amsmath and amssymb. To be published in Eur. Phys. J B

Objectives. To use 5-aminolevulinic acid (5-ALA) in diagnostic cystoscopy and during transurethral resection of the bladder (TURB) to treat transitional cell carcinoma. The efficacy of this new technique was compared with standard cystoscopy. Methods. The 5-ALA, instilled in the bladder 2 hours before cystoscopy, makes the pathologic tissue fluorescent when illuminated with blue light (375 to 400 nm). This allows a better recognition of the neoplastic forms for both diagnostic and therapeutic purposes during TURB. This method has been used since May 1997 on 49 patients in whom bladder tumor was diagnosed either immediately or during postchemotherapy follow-up. Results. One hundred seventy-nine biopsies were taken of fluorescent and nonfluorescent areas (3.5 per patient) to check the effectiveness of the new method compared with standard cystoscopy. A good correlation was found between 5-ALA cystoscopy and the histopathologic diagnosis, with a good sensitivity (87%). The 5-ALA cystoscopy allowed the diagnosis of a tumor in 24 patients with negative standard cystoscopic findings. Furthermore, 5-ALA cystoscopy detected 7 cases of carcinoma in situ. Neither local nor systemic (because of endovesical instillation) side effects were noted. Conclusions. We believe that 5-ALA could be routinely used in the diagnosis of superficial bladder tumors, as it was shown to improve the diagnostic sensitivity for carcinoma in situ and to reduce the risk of recurrence related to missed cancerous lesions or incomplete TURB.

One may impose to a system with spontaneous broken symmetry, boundary conditions which correspond to different pure states at two ends of a sample. For a discrete Ising-like broken symmetry, boundary conditions with opposite spins in two parallel limiting planes, generate an interface and a cost in free energy per unit area of the interface. For continuum symmetries the order parameter interpolates smoothly between the end planes carrying two different directions of the order parameter. The cost in free energy is then proportional to $L^{d-2}$ for a system of characteristic size L. The power of $L$ is related to the lower critical dimension, and the coefficient of this additional free energy vanishes at the critical temperature. In this note it is shown within a loop expansion that one does find the expected behavior of this twist free energy. This is a preamble to the study of situations where the broken continuum symmetry is believed to be more complex, as in Parisi's ansatz for the Edwards-Anderson spin glass., Comment: 15 pages, latex, no figure

The reparametrization transformation between ultrametrically organised states of replicated disordered systems is explicitly defined. The invariance of the longitudinal free energy under this transformation, i.e. reparametrization invariance, is shown to be a direct consequence of the higher level symmetry of replica equivalence. The double limit of infinite step replica symmetry breaking and n=0 is needed to derive this continuous gauge-like symmetry from the discrete permutation invariance of the n replicas. Goldstone's theorem and Ward identities can be deduced from the disappearence of the second (and higher order) variation of the longitudinal free energy. We recall also how these and other exact statements follow from permutation symmetry after introducing the concept of "infinitesimal" permutations., 16 pages, 3 figures

The replicated field theory of the random field Ising model involves the couplings of replicas of different indices. The resulting correlation functions involve a superposition of different types of long distance behaviours. However the $n=0$ limit allows one to discuss the renormalization group properties in spite of this phenomenon. The attraction of pairs of replicas is enhanced under renormalization flow and no stable fixed point is found. Consequently an instability occurs in the paramagnetic region, before one reaches the Curie line, signalling the onset of replica symmetry breaking., Comment: latex Replicas.tex, 1 file, 11 pages [SPhT-T00/111], submitted to Eur. Phys. J. B

Despite the many advantages provided by the ureteric stent, it produces a foreign body reaction and increases the risk of infection. We undertook a study on the rate of infection in a group of paediatric patients with ureteric stents; 40 ureteric stents, 6 to 9 F, were used in 36 children undergoing the following procedures: 18 pyeloplasties, 20 antireflux ureteric reimplantation and 2 uretero-rectal anastomoses. Only patients with sterile urine pre-operatively were included in the study. All received antibiotic cover in the post-operative period. Positive urine cultures were found in only 3 patients (7.5%). In spite of this low incidence, the urine specimens collected from all children 1 month after removal of the stent showed a much higher incidence of infection. It was concluded that ureteric stenting is a safe procedure with a low rate of infection provided that antibiotic cover is given.

Early diagnosis of bladder neoplasia at the moment makes use of urinary cytology and cystoscopy. The authors describe the results of a study on 62 patients (56 men and 6 women) with bladder neoplasia, and compare the results of urinary cytology to the BTA test (Bladder Tumor Antigen test), ones, after considering histological results of TURB (Trans Urethral Resection Bladder) or cystectomy. Sensibility of urinary cytology was quite better than BTA test sensibility (80.6% vs 48%). Finally it's described a study on 450 cases of istologically controlled bladder carcinomas, on which had been executed a cytological analysis before surgical treatment. The outcome of cytological diagnosis on 414 cases (92%) was neoplasia. On the basis of their experience, the authors regard cytology as a fundamental method in diagnostic iter and in follow-up of patients with bladder neoplasia.

Replica field theory for the Ising spin glass in zero magnetic field is studied around the upper critical dimension d=6. A scaling theory of the spin glass phase, based on Parisi's ultrametrically organised order parameter, is proposed. We argue that this infinite step replica symmetry broken (RSB) phase is nonperturbative in the sense that amplitudes of scaling forms cannot be expanded in term of the coupling constant w^2. Infrared divergent integrals inevitably appear when we try to compute amplitudes perturbatively, nevertheless the \epsilon-expansion of critical exponents seems to be well-behaved. The origin of these problems can be traced back to the unusual behaviour of the free propagator having two mass scales, the smaller one being proportional to the perturbation parameter w^2 and providing a natural infrared cutoff. Keeping the free propagator unexpanded makes it possible to avoid producing infrared divergent integrals. The role of Ward-identities and the problem of the lower critical dimension are also discussed., Comment: 14 pages

In a previous article we have shown, within the replica formalism, that the conventional picture of the random field Ising model breaks down, by the effect of singularities in the interactions between fields involving several replicas, below dimension eight. In the zero-replica limit several coupling constants have thus to be considered, instead of just one. As a result we had found that there is no stable fixed point in the vicinity of dimension six. It is natural to reconsider the problem in a dynamical framework, which does not require replicas, although the equilibrium properties should be recovered in the large time limit. Singularities in the zero-replica limit are a priori not visible in a dynamical picture. In this note we show that in fact new interactions are also generated in the stochastic approach. Similarly these interactions are found to be singular below dimension eight. These critical singularities require the introduction of a time origin $t_0$ at which initial data are given. The dynamical properties are thus dependent upon the waiting time. It is shown here that one can indeed find a complete correspondence between the equilibrium singularities in the $n=0$ limit, and the singularities in the dynamics when the initial time $t_0$ goes to minus infinity, with $n$ replaced by $-\frac{1}{t_0}$. There is thus complete coherence between the two approaches., 8 pages, latex, no figure

We reconsider Ising spins in a Gaussian random field within the replica formalism. The corresponding continuum model involves several coupling constants beyond the single one which was considered in the standard $\phi^4$ theory approach. These terms involve more than one replica, and therefore in a mean field theory they do not contribute to the zero-replica limit. However the fluctuations involving those extra terms are singular on the Curie line below eight dimensions, and by the time one reaches the dimension six, it is necessary to keep them in the renormalization group analysis. As a result it is found that there is no stable fixed point of order $(6-d)$. Whether this means that there is no expansion in powers of $(6-d)$, or that the transition is driven to first order by these fluctuations, is difficult to decide at this level, but it explains the failure of the $(d, d-2)$ correspondence. In this work we have not considered the possibility of a glassy phase in the would-be paramagnetic region, but in a subsequent work we shall present evidence for replica symmetry breaking in dimension lower than six., Comment: 9 pages, latex, no figure

The introduction of ``small permutations'' allows us to derive Ward-Takahashi identities for the spin-glass, in the Parisi limit of an infinite number of steps of replica symmetry breaking. The first identities express the emergence of a band of Goldstone modes. The next identities relate components of (the Replica Fourier Transformed) 3-point function to overlap derivatives of the 2-point function (inverse propagator). A jump in this last function is exhibited, when its two overlaps are crossing each other, in the special simpler case where one of the cross-overlaps is maximal., Comment: this new version includes acknowledgements to funding agencies