Search

Terrain traversability estimation is a fundamental task for supporting robot navigation on uneven surfaces. Recent learning-based approaches for predicting traversability from RGB images have shown promising results, but require manual annotation of a large number of images for training. To address this limitation, we present a method for traversability estimation on unlabeled videos that combines dataset synthesis, self-supervision and unsupervised domain adaptation. We pose the traversability estimation as a vector regression task over vertical bands of the observed frame. The model is pre-trained through self-supervision to reduce the distribution shift between synthetic and real data and encourage shared feature learning. Then, supervised training on synthetic videos is carried out, while employing an unsupervised domain adaptation loss to improve its generalization capabilities on real scenes. Experimental results show that our approach is on par with standard supervised training, and effectively supports robot navigation without the need of manual annotations. Training code and synthetic dataset will be publicly released at: . [ABSTRACT FROM AUTHOR]

Immune checkpoint blockade is effective for some patients with cancer, but most are refractory to current immunotherapies and new approaches are needed to overcome resistance1,2. The protein tyrosine phosphatases PTPN2 and PTPN1 are central regulators of inflammation, and their genetic deletion in either tumour cells or immune cells promotes anti-tumour immunity3–6. However, phosphatases are challenging drug targets; in particular, the active site has been considered undruggable. Here we present the discovery and characterization of ABBV-CLS-484 (AC484), a first-in-class, orally bioavailable, potent PTPN2 and PTPN1 active-site inhibitor. AC484 treatment in vitro amplifies the response to interferon and promotes the activation and function of several immune cell subsets. In mouse models of cancer resistant to PD-1 blockade, AC484 monotherapy generates potent anti-tumour immunity. We show that AC484 inflames the tumour microenvironment and promotes natural killer cell and CD8+ T cell function by enhancing JAK–STAT signalling and reducing T cell dysfunction. Inhibitors of PTPN2 and PTPN1 offer a promising new strategy for cancer immunotherapy and are currently being evaluated in patients with advanced solid tumours (ClinicalTrials.gov identifier ). More broadly, our study shows that small-molecule inhibitors of key intracellular immune regulators can achieve efficacy comparable to or exceeding that of antibody-based immune checkpoint blockade in preclinical models. Finally, to our knowledge, AC484 represents the first active-site phosphatase inhibitor to enter clinical evaluation for cancer immunotherapy and may pave the way for additional therapeutics that target this important class of enzymes.An orally bioavailable small-molecule active-site inhibitor of the phosphatases PTPN2 and PTPN1, ABBV-CLS-484, demonstrates immunotherapeutic efficacy in mouse models of cancer resistant to PD-1 blockade. [ABSTRACT FROM AUTHOR]

CAR-T therapy is a promising, novel treatment modality for B-cell malignancies and yet many patients relapse through a variety of means, including loss of CAR-T cells and antigen escape. To investigate leukemia-intrinsic CAR-T resistance mechanisms, we performed genome-wide CRISPR-Cas9 loss-of-function screens in an immunocompetent murine model of B-cell acute lymphoblastic leukemia (B-ALL) utilizing a modular guide RNA library. We identified IFNγR/JAK/STAT signaling and components of antigen processing and presentation pathway as key mediators of resistance to CAR-T therapy in vivo; intriguingly, loss of this pathway yielded the opposite effect in vitro (sensitized leukemia to CAR-T cells). Transcriptional characterization of this model demonstrated upregulation of these pathways in tumors relapsed after CAR-T treatment, and functional studies showed a surprising role for natural killer (NK) cells in engaging this resistance program. Finally, examination of data from B-ALL patients treated with CAR-T revealed an association between poor outcomes and increased expression of JAK/STAT and MHC-I in leukemia cells. Overall, our data identify an unexpected mechanism of resistance to CAR-T therapy in which tumor cell interaction with the in vivo tumor microenvironment, including NK cells, induces expression of an adaptive, therapy-induced, T-cell resistance program in tumor cells.CAR-T therapy is a promising treatment modality for B-cell malignancies, yet many patients relapse. Using an in vivo genomewide screen in a model of B cell leukemia, we identify an unexpected mechanism of CAR-T resistance in which interferon gamma from the in vivo tumor microenvironment induces an adaptive T-cell resistance program in tumor cells. [ABSTRACT FROM AUTHOR]

A Monte Carlo technique for the solution of the Wigner transport equation has been developed, based on the generation and annihilation of signed particles (Nedjalkov et al. in Phys Rev B 70:115319, 2004). A stochastic algorithm without time discretization error has been recently introduced (Muscato and Wagner in Kinet Relat Models 12(1):59–77, 2019). Its derivation is based on the theory of piecewise deterministic Markov processes. Numerical experiments are performed in the case of a GaAs resonant tunneling diode. Convergence of the time-splitting scheme to the no-splitting algorithm is demonstrated. The no-splitting algorithm is shown to be more efficient in terms of computational effort. [ABSTRACT FROM AUTHOR]

To understand the mechanisms that mediate germline genetic leukemia predisposition, we studied the inherited ribosomopathy Shwachman-Diamond syndrome (SDS), a bone marrow failure disorder with high risk of myeloid malignancies at an early age. To define the mechanistic basis of clonal hematopoiesis in SDS, we investigate somatic mutations acquired by patients with SDS followed longitudinally. Here we report that multiple independent somatic hematopoietic clones arise early in life, most commonly harboring heterozygous mutations in EIF6 or TP53. We show that germline SBDS deficiency establishes a fitness constraint that drives selection of somatic clones via two distinct mechanisms with different clinical consequences. EIF6 inactivation mediates a compensatory pathway with limited leukemic potential by ameliorating the underlying SDS ribosome defect and enhancing clone fitness. TP53 mutations define a maladaptive pathway with enhanced leukemic potential by inactivating tumor suppressor checkpoints without correcting the ribosome defect. Subsequent development of leukemia was associated with acquisition of biallelic TP53 alterations. These results mechanistically link leukemia predisposition to germline genetic constraints on cellular fitness, and provide a rational framework for clinical surveillance strategies. Understanding the molecular basis of leukaemia predisposition is essential for intervention. The authors here investigate germline genetic leukaemia predisposition by studying Shwachman-Diamond syndrome and report compensatory inactivating mutations in EIF6 and transforming biallelic TP53 alterations. [ABSTRACT FROM AUTHOR]

The use of robotics in neurosurgery and, particularly, in stereotactic neurosurgery, is becoming more and more adopted because of the great advantages that it offers. Robotic manipulators easily allow to achieve great precision, reliability, and rapidity in the positioning of surgical instruments or devices in the brain. The aim of this work was to experimentally verify a fully automatic 'no hands' surgical procedure. The integration of neuroimaging to data for planning the surgery, followed by application of new specific surgical tools, permitted the realization of a fully automated robotic implantation of leads in brain targets. An anthropomorphic commercial manipulator was utilized. In a preliminary phase, a software to plan surgery was developed, and the surgical tools were tested first during a simulation and then on a skull mock-up. In such a way, several tools were developed and tested, and the basis for an innovative surgical procedure arose. The final experimentation was carried out on anesthetized 'large white' pigs. The determination of stereotactic parameters for the correct planning to reach the intended target was performed with the same technique currently employed in human stereotactic neurosurgery, and the robotic system revealed to be reliable and precise in reaching the target. The results of this work strengthen the possibility that a neurosurgeon may be substituted by a machine, and may represent the beginning of a new approach in the current clinical practice. Moreover, this possibility may have a great impact not only on stereotactic functional procedures but also on the entire domain of neurosurgery. [ABSTRACT FROM AUTHOR]

Non-equilibrium electron transport in silicon nanowires has been tackled with a hydrodynamic model. This model has been formulated by taking the moments of the multisubband Boltzmann equation, coupled to the Schrödinger-Poisson system. Closure relations are obtained by means of the maximum entropy principle (MEP) of extended thermodynamics, including scattering of electrons with acoustic and nonpolar optical phonons. Simulation results for a quantum n − n − n silicon diode are shown. [ABSTRACT FROM AUTHOR]

One of the most time consuming phases in the development of an Unmanned Aerial Vehicle is the tuning of the control algorithms. In this paper the hardware and software suite developed for the self-tuning of the control loops of unmanned flying platforms is presented. The VOLCAN UAV has been used as platform to test and validate the developed architecture. The simplified control system of the VOLCAN UAV is described, together with the Graphical User Interface that allows the rapid automatic tuning of the system by means of Åström and Hägglund's method. The Hardware in the Loop architecture used to test both the control algorithms and the tuning procedure is presented in the final part of the paper, together with the obtained experimental results. [ABSTRACT FROM AUTHOR]

This paper presents the software architecture that was developed to evaluate the performance of different Global Navigation Satellite Systems (GNSSs) and Satellite/Ground-Based Augmentation Systems for the localization and navigation of an autonomous robotic lawn-mower. In particular, a complete simulation environment has been developed to analyse the system performance obtained by adopting the future European GNSSs when GALILEO will be fully operative. Moreover, this tool has been adopted in the development phase of a precise GNSS-based localization system and developed within the MOW-BY-SAT project, an FP7 project funded by the European Commission; this architecture relies on an innovative algorithm that allows for a Real Time Kinematic localization system, while requiring only a pair of low-cost GPS receivers. The results show the validity of the developed localization and control architecture and the potential of the future European GALILEO system. [ABSTRACT FROM AUTHOR]

An extended hydrodynamic model will be used for the coupled system of electrons and phonons. This system is formed by a set of balance equations derived from the Bloch-Boltzmann-Peierls (BBP) kinetic equations applying the moment method and solving the problem of the closure by means of the Maximum Entropy Principle of Extended Thermodynamics. By using this model with a suitable limit, thermoelectric effects in bulk silicon are investigated. [ABSTRACT FROM AUTHOR]

A hydrodynamic model for silicon quantum wires is formulated by taking the moments of the multisubband Boltzmann equation, coupled to the Schrödinger-Poisson system. Explicit closure relations for the fluxes and production terms (i.e. the moments on the collisional operator) are obtained by means of the Maximum Entropy Principle of Extended Thermodynamics, including scattering of electrons with acoustic and non-polar optical phonons. By using this model, thermoelectric effects are investigated. [ABSTRACT FROM AUTHOR]

n Energy Transport Model describing the electron transport in semiconductors coupled with the heating of the crystal lattice is presented. It has been obtained by taking the moments of the coupled Boltzmann equations for the electrons and phonons, by using the Maximum Entropy Principle of Extended Thermodynamics, and by performing an appropriate scaling. The main advantage of this model is that the transport coefficients are explicitly determined. [ABSTRACT FROM AUTHOR]

Abstract  This paper presents an overview of the Volcan Project, whose goal is the realization of an autonomous aerial system able to perform aerial surveillance of volcanic areas and to analyze the composition of gases inside volcanic plumes. There are increasing experimental evidences that measuring the chemical composition of volcanic gases can contribute to forecast volcanic eruptions. However, in situ gas sampling is a difficult operation and often exposes scientists to significant risks. At this aim, an Unmanned Aircraft System equipped with remote sensing technologies, able to sense the plume in the proximity of the crater, has been developed. In this paper, the aerial platform will be presented, together with the problems related to the flight in a hard scenario like the volcanic one and the tests performed with the aim of finding the right configuration for the vehicle. The developed autonomous navigation system and the sensors unit for gas analysis will be introduced; at the end, several experimental results will be described. [ABSTRACT FROM AUTHOR]

An hydrodynamic model for electron and phonon transport in silicon semiconductors has been formulated, on the basis of the Maximum Entropy Principle, in order to describe off-equilibrium phenomena in submicron silicon devices. [ABSTRACT FROM AUTHOR]

Copyright of Il Nuovo Cimento: B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Relativistic magnetofluiddynamics is a subject of importance for astrophysics and laboratory plasma physics. In this paper some exact solutions of the full nonlinear equations of relativistic magnetofluiddynamics are studied, which correspond to simple waves. The Riemann invariants are explicitly determined for various cases of noticeable physical interest. [ABSTRACT FROM AUTHOR]

A set of closed hydrodynamic-like equations is derived from Boltzmann's transport equation (BTE) describing charge transport in semiconductors. The moment hierarchy is closed by using the entropy principle: such closure is checked with Monte Carlo simulations for silicon. [ABSTRACT FROM AUTHOR]

The article presents a study which investigated triclopyr herbicide excretion in a bovine. A lactating Holstein was fed with triclopyr for four days. Results revealed that the herbicide was not detected in the feces or milk samples. It notes that the association between triclopyr field use and cattle toxicity may involve misuse of the herbicide causing overexposure in the animals.

Recipients of renal transplants are known to have an increased incidence of cancer, which is believed to he related to the use of immunosuppressive drugs used to prevent rejection. Although the risks of lymphoma and Kaposi's sarcoma are clearly increased in this setting, the association with colon cancer is controversial. We report a 44-yr-old woman, 20 yr post-renal transplant, and with no family history of colorectal cancer or polyps, who was found to have synchronous, poorly differentiated colon cancers associated with extensive abdominal lymph node, bone marrow, and bone (skull) metastasis. The long term immunosuppressive drugs that she had received may have been an important factor in her tumor development and/or progression. Our case and literature review suggest a possible mild, increased risk of colon cancer development in patients after renal transplantation. [ABSTRACT FROM AUTHOR]

Silicon nanowires (SiNWs) are quasi-one-dimensional structures in which electrons are spatially confined in two directions and they are free to move in the orthogonal direction. The subband decomposition and the electrostatic force field are obtained by solving the Schrödinger-Poisson coupled system. The electron transport along the free direction can be tackled using a hydrodynamic model, formulated by taking the moments of the multisubband Boltzmann equation. We shall introduce an extended hydrodynamic model where closure relations for the fluxes and production terms have been obtained by means of the Maximum Entropy Principle of Extended Thermodynamics, and in which the main scattering mechanisms such as those with phonons and surface roughness have been considered. By using this model, the low-field mobility of a Gate-All-Around SiNW transistor has been evaluated. [ABSTRACT FROM AUTHOR]