What Are Polymorphically-Typed Ambients?

Abstract: The Ambient Calculus was developed by Cardelli and Gordon as a formal framework to study issues of mobility and migrant code. We consider an Ambient Calculus where ambients transport and exchange programs rather that just inert data. We propose different senses in which such a calculus can be said to be polymorphically typed, and design accordingly a polymorphic type system for it. Our type system assigns types to embedded programs and what we call behaviors to processes; a denotational semantics of behaviors is then proposed, here called trace semantics, underlying much of the remaining analysis. We state and prove a Subject Reduction property for our polymorphically typed calculus. Based on techniques borrowed from finite automata theory, type-checking of fully type-annotated processes is shown to be decidable; the time complexity of our decision procedure is exponential (this is a worst-case in theory, arguably not encountered in practice). Our polymorphically-typed calculus is a conservative extension of the typed Ambient Calculus originally proposed by Cardelli and Gordon

Polymer-grafted gold nanoparticles for cancer treatment: synthesis and evaluation of their radiosensitizing properties

International audienceToday, even though treatments have much improved, cancer is still a leading cause of death in the world, being responsible for 1 death out of 6. Radiotherapy is widely used for tumor treatment, but suffers from side effects due to the irradiation of healthy surrounding tissues. Another issue is the radioresistance developed by some tumor cells, which implies to increase the involved doses. The challenge remains to deliver curative doses to tumor tissues while sparing sound ones. Hence the use of tumor-located radiosensitizers is a promising way to improve the efficacy of radiotherapy. High-Z materials have been known for several decades to amplify the damaging effects of both photon and ion radiations. Various nanoparticles have already been developed to take advantage of this property: gold, platinum and gadolinium are amongst the most investigated elements. A well-controlled synthesis is key to obtain stable and scalable nano-objects. Here, various polymers were grafted onto metallic nanoparticles to improve stability and biocompatibility and to facilitate subsequent functionalization. Advanced methods of characterization attested both robustness and reproducibility of the synthesis procedure. Moreover, promising results were obtained regarding the radioenhancing properties of these hybrid nanocompounds. Therefore, special attention has been given to the underlying mechanisms of the assessed radiosensitization, since they are not fully understood yet. Synthesis of polymer-grafted gold nanoparticles was performed through an in situ method, via the reduction of gold salts in the presence of polymeric ligands mainly prepared using controlled radical polymerization. The resulting nano-objects were fully characterized by thermogravimetric analysis, inductively coupled plasma mass spectrometry (ICP-MS), transmission electronic microscopy and small-angle x-ray and neutron scattering. Interactions between our nanocompounds and biological systems were studied in order to better understand the mechanisms at play. At the cellular scale, three aspects were examined for each type of nanoparticles: cellular uptake, cytotoxicity and radiosensitizing properties, through ICP-MS measurements, cell proliferation assays and clonogenic assays respectively. All irradiations were performed while keeping the delivered doses to low values (under 30 Gy) that are typical of clinic reality. Different types of radiations were tested, in order to compare their effects and their synergy with the nanocompounds. The synthesized nano-objects have shown great potential to enhance radiation cancer treatment. Their stability and controlled surface chemistry have allowed to develop multiple strategies in order to optimize their radiosensitizing effect and in vitro behavior

Review of biorthogonal coupled cluster representations for electronic excitation

Single reference coupled-cluster (CC) methods for electronic excitation are based on a biorthogonal representation (bCC) of the (shifted) Hamiltonian in terms of excited CC states, also referred to as correlated excited (CE) states, and an associated set of states biorthogonal to the CE states, the latter being essentially configuration interaction (CI) configurations. The bCC representation generates a non-hermitian secular matrix, the eigenvalues representing excitation energies, while the corresponding spectral intensities are to be derived from both the left and right eigenvectors. Using the perspective of the bCC representation, a systematic and comprehensive analysis of the excited-state CC methods is given, extending and generalizing previous such studies. Here, the essential topics are the truncation error characteristics and the separability properties, the latter being crucial for designing size-consistent approximation schemes. Based on the general order relations for the bCC secular matrix and the (left and right) eigenvector matrices, formulas for the perturbation-theoretical (PT) order of the truncation errors (TEO) are derived for energies, transition moments, and property matrix elements of arbitrary excitation classes and truncation levels. In the analysis of the separability properties of the transition moments, the decisive role of the so-called dual ground state is revealed. Due to the use of CE states the bCC approach can be compared to so-called intermediate state representation (ISR) methods based exclusively on suitably orthonormalized CE states. As the present analysis shows, the bCC approach has decisive advantages over the conventional CI treatment, but also distinctly weaker TEO and separability properties in comparison with a full (and hermitian) ISR method

Using Corticomuscular and Intermuscular Coherence to Assess Cortical Contribution to Ankle Plantar Flexor Activity During Gait

The present study used coherence and directionality analyses to explore whether the motor cortex contributes to plantar flexor muscle activity during the stance phase and push-off phase during gait. Subjects walked on a treadmill, while EEG over the leg motorcortex area and EMG from the medial gastrocnemius and soleus muscles was recorded. Corticomuscular and intermuscular coherence were calculated from pair-wise recordings. Significant EEG-EMG and EMG-EMG coherence in the beta and gamma frequency bands was found throughout the stance phase with the largest coherence towards push-off. Analysis of directionality revealed that EEG activity preceded EMG activity throughout the stance phase until the time of push-off. These findings suggest that the motor cortex contributes to ankle plantar flexor muscle activity and forward propulsion during gait

Outcomes based on prior therapy in the phase 3 METEOR trial of cabozantinib versus everolimus in advanced renal cell carcinoma

Altres ajuts: We thank the patients, their families, the investigators and site staff, and the study teams who participated in the METEOR trial. This study was funded by Exelixis, Inc. Patients treated at Memorial Sloan Kettering Cancer Center were supported in part by Memorial Sloan Kettering Cancer Center Support Grant/Core Grant (P30 CA008748). Editorial support was provided by Fishawack Communications (Conshohocken, PA, USA) and funded by Exelixis.In the phase 3 METEOR trial, cabozantinib improved progression-free survival (PFS), objective response rate (ORR), and overall survival (OS) versus everolimus in patients with advanced renal cell carcinoma (RCC), after prior antiangiogenic therapy. Outcomes were evaluated for subgroups defined by prior therapy with sunitinib or pazopanib as the only prior VEGFR inhibitor, or prior anti-PD-1/PD-L1 therapy. For the prior sunitinib subgroup (N = 267), median PFS for cabozantinib versus everolimus was 9.1 versus 3.7 months (HR 0.43, 95% CI 0.32-0.59), ORR was 16% versus 3%, and median OS was 21.4 versus 16.5 months (HR 0.66, 95% CI 0.47-0.93). For the prior pazopanib subgroup (N = 171), median PFS for cabozantinib versus everolimus was 7.4 versus 5.1 months (HR 0.67, 95% CI 0.45-0.99), ORR was 19% versus 4%, and median OS was 22.0 versus 17.5 months (HR 0.66, 95% CI 0.42-1.04). For prior anti-PD-1/PD-L1 therapy (N = 32), median PFS was not reached for cabozantinib versus 4.1 months for everolimus (HR 0.22, 95% CI 0.07-0.65), ORR was 22% versus 0%, and median OS was not reached versus 16.3 months (HR 0.56, 95% CI 0.21-1.52). Cabozantinib was associated with improved clinical outcomes versus everolimus in patients with advanced RCC, irrespective of prior therapy, including checkpoint inhibitor therapy

Elevated neutrophil and monocyte counts in peripheral blood are associated with poor survival in patients with metastatic melanoma: a prognostic model

We aimed to create a prognostic model in metastatic melanoma based on independent prognostic factors in 321 patients receiving interleukin-2 (IL-2)-based immunotherapy with a median follow-up time for patients currently alive of 52 months (range 15–189 months). The patients were treated as part of several phase II protocols and the majority received treatment with intermediate dose subcutaneous IL-2 and interferon-α. Neutrophil and monocyte counts, lactate dehydrogenase (LDH), number of metastatic sites, location of metastases and performance status were all statistically significant prognostic factors in univariate analyses. Subsequently, a multivariate Cox's regression analysis identified elevated LDH (P<0.001, hazard ratio 2.8), elevated neutrophil counts (P=0.02, hazard ratio 1.4) and a performance status of 2 (P=0.008, hazard ratio 1.6) as independent prognostic factors for poor survival. An elevated monocyte count could replace an elevated neutrophil count. Patients were assigned to one of three risk groups according to the cumulative risk defined as the sum of simplified risk scores of the three independent prognostic factors. Low-, intermediate- and high-risk patients achieved a median survival of 12.6 months (95% confidence interval (CI), 11.4–13.8), 6.0 months (95% CI, 4.8–7.2) and 3.4 months (95% CI, 1.2–5.6), respectively. The low-risk group encompassed the majority of long-term survivors, whereas the patients in the high-risk group with a very poor prognosis should probably not be offered IL-2-based immunotherapy

Medial gastrocnemius muscle stiffness cannot explain the increased ankle joint range of motion following passive stretching in children with cerebral palsy.

Stretching is often used to increase/maintain joint range of motion (ROM) in children with cerebral palsy (CP) but the effectiveness of these interventions is limited. Therefore, this study aimed to determine the acute changes in muscle-tendon lengthening properties that contribute to increased ROM after a bout of stretching in children with CP. Eleven children with spastic CP (age:12.1(3)y, 5/6 hemiplegia/diplegia, 7/4 GMFCS level I/II) participated in this study. Each child received 3 sets of 5 × 20 s passive, manual static dorsiflexion stretches separated by 30 s rest, and 60 s rest between sets. Pre- and immediately post-stretching, ultrasound was used to measure medial gastrocnemius fascicle lengthening continuously over the full ROM and an individual common ROM pre- to post-stretching. Simultaneously, 3D motion of two marker clusters on the shank and the foot was captured to calculate ankle angle, and ankle joint torque was calculated from manually applied torques and forces on a 6DoF load cell. After stretching, ROM was increased (9.9° (12.0), P = 0.005). Over a ROM common to both pre and post measurements, there were no changes in fascicle lengthening or torque. The maximal ankle joint torque tolerated by the participants increased (2.9(2.4) Nm, P = 0.003) and at this highest passive torque maximal fascicle length was 2.8(2.4) mm greater (P = 0.009) when compared to before stretching. These results indicate that the stiffness of the muscle fascicles in children with CP remain unaltered by an acute bout of stretching. This article is protected by copyright. All rights reserved