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In 2005 Milan Municipality launched the "Adopt a green spot" model initiative, to restore and maintain scattered and marginal green areas, following a Payment for Ecosystem Services (PES) scheme. The PES scheme was designed in the form of two standardized typologies of voluntary agreements – sponsorship and collaboration - allowing flexibility in the commitment of involved private stakeholders, including condominiums, NGOs, and the business. 502 agreements, for a total surface of 265.398 m2, have been signed up to now. The paper analysis the design components of the PES scheme which determines its capacity to be replicated in different contexts involving a variety of stakeholders. The main elements enabling the success of the PES scheme are i) the flexibility of the voluntary agreements designed to meet the needs of various stakeholders; ii) the variety of green areas included in the initiative; iii) public recognition which makes it possible to attract firms iv) low transaction costs borne by the stakeholders. The financial resources committed, even if representing a small portion of the total social benefit generated, are sufficient to ensure an adequate requalification and maintenance of small green areas, often neglected because of scarcity of public financing. The replication capacity of this PES scheme makes it a model initiative. Given its characteristics and flexibility, it has been used for the definition of more than 500 agreements with different stakeholders, and for these reasons the policy design approach can be suitable for the replication in other urban contests. • The PES scheme was designed in the form of two standardized typologies of voluntary agreements – sponsorship and collaboration. • PES model has been replicated over the years. 502 agreements, for a total surface of 265.398 m2, have been signed up to now. • PES design components determine its capacity to be replicated in different contexts involving a variety of stakeholders. • Financial resources do not fully reflect the total value generated but are sufficient to re-qualify and maintain green areas. [ABSTRACT FROM AUTHOR]

Abstract The increasing use of curved surface sliding bearings as seismic isolators benefits from the improvement of analytical models that can accurately capture their experimental performance and enhance the predictive capability of nonlinear response history analyses. The mathematical formulation proposed in this paper aims at addressing the variability of the coefficient of friction based on experimental data that can be retrieved from prototype tests on Curved Surface Sliders. The formulation accounts for variation in the coefficient of friction with the instantaneous change of axial load and sliding velocity at the contact interface, and the accumulated heat due to cyclic motion; furthermore, it incorporates new features such as the static friction developed in the transition from the pre-sliding phase to the dynamic sliding condition. The proposed model has been coded in the object-oriented finite element software OpenSees by modifying the standard SingleFPSimple3d element that describes the force – displacement relationship of a bearing comprising one concave sliding surface and a spherical articulation. The main novelties of the new CSSBearing_BVNC element are inclusion of the static friction before the breakaway and degradation of kinetic friction induced by the heat developed during the motion of the articulated slider. The primary assumptions in the development of the friction model and the verification of the newly developed element are validated by agreement with available data. A case study helps to demonstrate the improved prediction capability of the new bearing element over its standard counterpart when applied to real situations, such as estimating a +50% increase in isolator displacement, superstructure drift and base shear demand under high intensity earthquakes, and possible non-activation of the sliding isolators under weak or medium intensity earthquakes. Highlights • A friction law accounting for the effects of axial load, velocity and heating is presented. • Contribution of static friction before the breakaway is included in the model. • The friction law is coded in an OpenSees element of concave surface sliding bearing. • Comparative evaluation of the new bearing element is performed through a case study. • A more accurate estimation of displacement and force demands is provided. [ABSTRACT FROM AUTHOR]

We analyse super non-Abelian T-duality for principal chiral models, symmetric space sigma models, and semi-symmetric space sigma models for general Lie supergroups. This includes T-duality along both bosonic and fermionic directions. As an example, we perform the explicit dualisation of the OSp (1 | 2) principal chiral model, and, whilst the target superspace of this model is a three-dimensional supergravity background, we find that its super non-Abelian T-dual falls outside the class of such backgrounds. [ABSTRACT FROM AUTHOR]

Summary: Study objectives: To test safety and tolerability of long-term moxifloxacin in resistant tuberculosis (TB) patients and patients with intolerance to first line anti-TB drugs. Design: Clinical evaluation of adverse events (AEs) during prolonged moxifloxacin treatment. Setting: TB Unit of the Regional TB Reference Center, Villa Marelli Institute, Niguarda Ca’Granda Hospital, Milan, Italy Patients and interventions: Patients treated with moxifloxacin, 400mg orally once daily for TB in the Villa Marelli Institute from January 2001 to December 2003 were enrolled. Results: Thirty-eight patients were treated with moxifloxacin at the Villa Marelli Institute in the study period, for multidrug resistant (MDR) TB (14, 36.8%), for intolerance to first line anti-TB drugs (9, 23.7%), for combined resistance and intolerance to first line anti-TB drugs (12, 31.6%), other reasons (3, 7.9%). The mean duration of moxifloxacin treatment was 6.3±5.2 months. Twelve (31.6%) patients reported at least an AE due to moxifloxacin, mostly gastrointestinal (8, 21.0%), general (5, 13.2%) and central nervous system (3, 7.9%) AEs. In 4 (10.5%) patients the drug was withdrawn for major AEs; no irreversible or fatal events were recorded. Most of the patients (31, 81.6%) reported a treatment success, even if the success rate was lower in MDR TB patients (8/14, 51.7%). Conclusions: Despite the fact that a large proportion of patients experienced at least an AE due to moxifloxacin, the drug resulted safe in the long-term administration for complicated TB cases. [Copyright &y& Elsevier]

This paper reports on the effects of hygrothermal aging at 70 °C in water, and at 80% relative humidity, on the molar mass and thermal properties of recycled poly(ethylene terephthalate) and its short glass fibre composites.During the initial period of exposure, water uptake increases linearly with the square root of time and apparent diffusivity decreases as fibre content increases and as relative humidity decreases. Samples exposed to 80% RH reach an equilibrium water content, while samples immersed in water do not. Composites absorb more water than expected on the basis of matrix sorption behaviour, thus suggesting that other mechanisms, like capillarity and/or transport by microcracks, are active.The observed molar mass decrease has been successfully modelled as a pseudo first-order reaction whose rate constant depends on the humidity conditions.Due to a chemicrystallization process the crystallinity of rPET and its composites increases during aging. The glass transition temperature, as measured on the second DSC scan, depends on the number-average molar mass reached during hygrothermal aging. [Copyright &y& Elsevier]

This paper reports on the effects of hygrothermal aging at 70°C in water and at 80% relative humidity, on the thermo-mechanical properties, molar mass and microstructure of recycled poly(ethylene terephthalate) (rPET) and its short glass fibres composites.For all the investigated materials, the elastic mechanical properties (tensile and storage moduli) determined at low strain levels resulted practically unaffected by hygrothermal aging under the selected conditions. On the other hand, a marked reduction of the tensile strength and apparent fracture toughness has been observed for rPET matrix and its composites during hygrothermal aging, more markedly for materials immersed in water than for those aged at 80% RH. Both properties resulted to be related on the molar mass of the rPET matrix, that decreased during hygrothermal aging as a consequence of the hydrolysis process.The materials glass transition, evaluated as the temperature of the loss factor peak, increased during hygrothermal aging due to the progressively restricted mobility of the amorphous phase caused by a concurrent crystallinity increase. This crystallization process (chemicrystallization) is favoured by temperature, by the plasticizing effect of water and by the reduction of molar mass.Consistently with the mechanical measurements, the morphology of fracture surfaces exposed to hygrothermal aging in water revealed a reduction of plastic deformation of the rPET matrix and a weakening of the fibre–matrix interface for rPET composites. [Copyright &y& Elsevier]

We study the large N degeneracy in the structure of the four-point amplitudes of 1/2-BPS operators of arbitrary weight k in perturbative N=4 SYM theory. At one loop (order g2) this degeneracy manifests itself in a smaller number of independent conformal invariant functions describing the amplitude, compared to AdS5 supergravity results. To study this phenomenon at the two-loop level (order g4) we consider a particular N=2 hypermultiplet projection of the general N=4 amplitude. Using the formalism of N=2 harmonic superspace we then explicitly compute this four-point correlator at two loops and identify the corresponding conformal invariant functions.

In the cases of 1/2-BPS operators of arbitrary weight k in perturbative N=4 SYM theory. At one loop (order g2) this degeneracy manifests itself in a smaller number of independent conformal invariant functions describing the amplitude, compared to AdS5 supergravity results. To study this phenomenon at the two-loop level (order g4) we consider a particular N=2 hypermultiplet projection of the general N=4 amplitude. Using the formalism of N=2 harmonic superspace we then explicitly compute this four-point correlator at two loops and identify the corresponding conformal invariant functions.In the cases of 1/2-BPS operators of weight k=3 and k=4 the one-loop large N degeneracy is lifted by the two-loop corrections. However, for weight k>4 the degeneracy is still there at the two-loop level. This behavior suggests that for a given weight k the degeneracy will be removed if perturbative corrections of sufficiently high order are taken into account. These results are in accord with the AdS/CFT duality conjecture. [Copyright &y& Elsevier]

Using the bicomplex approach we discuss an integrable noncommutative system in two-dimensional Euclidean space. It is described by an equation of motion which reduces to the ordinary sine-Gordon equation when the noncommutation parameter is removed, plus a constraint equation which is nontrivial only in the noncommutative case. The implications of this constraint, which is required by integrability but seems to reduce the space of classical solutions, remain to be understood. We show that the system has an infinite number of conserved currents and we give the general recursive relation for constructing them. For the particular cases of lower spin nontrivial currents we work out the explicit expressions and perform a direct check of their conservation. These currents reduce to the usual sine-Gordon currents in the commutative limit. We find classical “localized” solutions to first order in the noncommutativity parameter and describe the Backlund transformations for our system. Finally, we comment on the relation of our noncommutative system to the commutative sine-Gordon system. [Copyright &y& Elsevier]

We study a class of non-protected local composite operators which occur in the R-symmetry singlet channel of the OPE of two stress-tensor multiplets in N=4 SYM. At tree level these are quadrilinear scalar dimension four operators, two single-traces and two double-traces. In the presence of interaction, due to a non-trivial mixing under renormalization, they split into linear combinations of conformally covariant operators. We resolve the mixing by computing the one-loop two-point functions of all the operators in an N=1 setup, then diagonalizing the anomalous dimension matrix and identifying the quasiprimary operators. We find one operator whose anomalous dimension is negative and suppressed by a factor of 1/N2 with respect to the anomalous dimensions of the Konishi-like operators. We reveal the mechanism responsible for this suppression and argue that it works at every order in perturbation theory. In the context of the AdS/CFT correspondence such an operator should be dual to a multiparticle supergravity state whose energy is less than the sum of the corresponding individual single-particle states. [Copyright &y& Elsevier]

We derive a geometric formulation of the 2d central charge c r from infinite families of 4d N = 1 superconformal field theories topologically twisted on constant curvature Riemann surfaces. They correspond to toric quiver gauge theories and are associated to D3 branes probing five dimensional Sasaki–Einstein geometries in the AdS/CFT correspondence. We show that c r can be expressed in terms of the areas of the toric diagram describing the moduli space of the 4d theory, both for toric geometries with smooth and singular horizons. We also study the relation between a-maximization in 4d and c-extremization in 2d, giving further evidences of the mixing of the baryonic symmetries with the exact R-current in two dimensions. [ABSTRACT FROM AUTHOR]

Background & Aims: It is uncertain whether mucosal healing after the first course of corticosteroids therapy predicts outcome in patients with ulcerative colitis (UC). We evaluated whether early clinical and endoscopic responses to this therapy are associated with late outcomes in UC. Methods: Patients with newly diagnosed UC who were prescribed corticosteroid therapy (n = 157) were followed up for 5 years. They were evaluated using clinical (Powel–Tuck [PT]) and endoscopic (Baron) indexes after 3 and 6 months, then every 6 months. Outcomes at month 3 (early response) were used to identify patients with complete (group A: PT, 0–1; Baron, 0), partial (group B: PT, 0–1; Baron, 1–3), or no response (group C: persistence of clinical and endoscopic activity). The association between early and late outcomes was assessed. Results: After 5 years, there were significant differences between complete and partial responders in the rates of hospitalization (25% in group A vs 48.7% in group B; P = .0152; odds ratio [OR], 2.85; 95% confidence interval [CI], 1.21–6.72), immunosuppression therapy (5% in group A vs 25.6% in group B; P = .0030; OR, 6.55; 95% CI, 1.67–25.67), colectomy (3.3% in group A vs 18.0% in group B; P = .0265; OR, 6.34; 95% CI, 1.24–32.37), and their combination (26.7% in group A vs 48.7% in group B; P = .0249; OR, 2.61; 95% CI, 1.12–6.11). After multivariate analysis, lack of mucosal healing was the only factor associated with negative outcomes at 5 years (immunosuppressors: hazard risk [HR], 10.581; 95% CI, 2.193–51.039; P = .0033; hospitalization: HR, 3.634; 95% CI, 1.556–8.485; P = .0029; colectomy: HR, 8.397; 95% CI, 1.278–55.186; P = .0268). Conclusions: No mucosal healing after corticosteroid therapy is associated with a more aggressive disease course. [ABSTRACT FROM AUTHOR]

The Power of Food Scale (PFS) is a questionnaire for self-assessing the motivation to consume palatable foods, especially in environments where food is abundant and constantly available. This study aimed to a) assess the factorial structure of the PFS in a Brazilian sample and b) examine the relationship between the power of food and body image dissatisfaction and BMI. The PFS and Body Shape Questionnaire (BSQ) were applied to a sample of 300 adults. Data were analysed using confirmatory factor analysis. Composite reliability (CR) was used to verify factor reliability. A partial least squares structural equation model was used to verify the effect of the PFS score on body image dissatisfaction. The PFS had an adequate factorial structure in this Brazilian sample, showing three well-defined factors: food available (CR = 0.91), food tasted (CR = 0.84), and food present (CR = 0.87). The BSQ showed one reliable factor (CR = 0.97). The power of the food aggregate factor significantly predicted body mass index (β = 0.16; p = .01) and body image dissatisfaction (β = 0.46; p < .001). The effect size was small for body mass index (f2 = 0.02) and medium for body image dissatisfaction (f2 = 0.26). The food present factor also had a slightly higher average among the three PFS factors. Women had higher PFS scores than men. Understanding the role that this motivation plays in physical and psychological outcomes such as body dissatisfaction can contribute to developing treatment strategies and support health professionals' performance in clinical settings. [ABSTRACT FROM AUTHOR]

The incidence of infections with Extended-spectrum β-lactamase (ESBL) producing Escherichia coli (E. coli) is increasing and represents a threat to human and animal health. Pet animals have been reported as potential carriers of clinically important multi-drug-resistant E. coli but information on the role of stray cats is limited. The aim of this study was to determine the prevalence of ESBL producing E. coli in cats living in colonies from Northern Italy. Stray cats admitted to the Veterinary Teaching Hospital of Lodi, University of Milan, only for mandatory sterilization programs were sampled in 2020. Rectal swabs collected from each cat were enriched and cultured on solid chromogenic selective media. Species identification of phenotypically ESBL-producing isolates was accomplished via matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) using the direct transfer method. Polymerase Chain Reaction (PCR) was used to detect bla CTX-M , bla SHV and bla TEM gene codes and isolates were divided into different phylogenetic groups. Isolates of ESBL-producing E. coli were subjected to antimicrobial susceptibility testing using minimum inhibitory concentration (MIC) determination. A total of 79 cats from 12 colonies were screened. Four (5.1%) stray cats from three different cat colonies were found positive for ESBL-producing E. coli. The ESBL-producing E. coli isolates exhibited a multidrug-resistant phenotype, with all isolates resistant to ampicillin, cefazolin, cefovecin, cefpodoxime, cephalexin and tetracycline. In the multidrug-resistant E. coli , the PCR results showed that bla CTX-M was the predominant ESBL gene identified with all four isolates carrying the bla(CTX-M-1)-group β-lactamase genes, followed by bla TEM which was found in three isolates, whereas bla SHV was not detected. Three of the ESBL-positive E. coli isolates belonged to commensal groups (A; B1), whereas one isolate belonged to the B2 phylogroup Our results provide important baseline information on the carriage of multidrug-resistant E. coli among stray cats. Considering that the presence of antimicrobial selection pressure is unlikely or represents sporadic events in cat colonies, our results also suggest that stray cats may be sentinels for ESBL-producing E. coli circulation. Further studies using a One Health approach are needed to understand the drivers of antimicrobial resistance at the human-animal-environmental interface. [ABSTRACT FROM AUTHOR]

Abstract: We study numerically the dynamics of a chain of particles subjected to an on site restoring nonlinear force and a first neighbor harmonic coupling. We excite the first linear mode and investigate the distribution of the average harmonic energies at metastable regime, in the spirit of Fermi Pasta Ulam experiment. The limit distribution turns out to strongly depend on the boundary conditions. A theoretical discussion of the phenomenon is also given. [Copyright &y& Elsevier]

Abstract: We study exact string backgrounds (WZW models) generated by nonsemisimple algebras which are obtained as double extensions of generic D-dimensional semisimple algebras. Even if a suitable change of coordinates always exists which reduces these backgrounds to be the product of the non-trivial background associated to the original algebra and two-dimensional Minkowski, under Inönü–Wigner contraction the algebra reduces to a Nappi–Witten algebra and the corresponding plane wave spacetime, no more factorized, is the Penrose limit of the original background. We construct the spectrum of D-branes for the double-extended background and study their behavior under the Penrose limit. While in general D-branes become singular in this limit, we prove that a class of solutions with a well-defined limit exists and it gives rise to the spectrum of configurations of the contracted model. Therefore, all D-branes of the plane wave background can be obtained as suitable contractions of original ones. We also discuss the Penrose limit at the quantum level and argue that the procedures of contraction and quantization commute. [Copyright &y& Elsevier]