134 research outputs found
Combining Shape Completion and Grasp Prediction for Fast and Versatile Grasping with a Multi-Fingered Hand
Grasping objects with limited or no prior knowledge about them is a highly
relevant skill in assistive robotics. Still, in this general setting, it has
remained an open problem, especially when it comes to only partial
observability and versatile grasping with multi-fingered hands. We present a
novel, fast, and high fidelity deep learning pipeline consisting of a shape
completion module that is based on a single depth image, and followed by a
grasp predictor that is based on the predicted object shape. The shape
completion network is based on VQDIF and predicts spatial occupancy values at
arbitrary query points. As grasp predictor, we use our two-stage architecture
that first generates hand poses using an autoregressive model and then
regresses finger joint configurations per pose. Critical factors turn out to be
sufficient data realism and augmentation, as well as special attention to
difficult cases during training. Experiments on a physical robot platform
demonstrate successful grasping of a wide range of household objects based on a
depth image from a single viewpoint. The whole pipeline is fast, taking only
about 1 s for completing the object's shape (0.7 s) and generating 1000 grasps
(0.3 s).Comment: 8 pages, 10 figures, 3 tables, 1 algorithm, 2023 IEEE-RAS
International Conference on Humanoid Robots (Humanoids), Project page:
https://dlr-alr.github.io/2023-humanoids-completio
Öffentlich-private Partnerschaften und kommunale Verschuldung
The present paper examines whether there is a connection between the debt of a municipality and its tendency to implement infrastructure projects in the form of public-private partnerships. Similar to loans, public-private partnerships (PPPs) postpone public sector payment obligations into the future. It is therefore sometimes argued that local authorities misuse PPPs to disguise the true level of public debt. Municipalities that have already used the debt instrument intensively should then have a higher PPP tendency. The present paper does not find any reliable evidence for this. Employing data of the state of North Rhine-Westfalia the paper finds that municipalities with PPPs do in fact have higher levels of debt. In an econometric analysis, however, the effect of debt on the number of PPPs turns out to be insignificant and also quantitatively negligible
Learning-Based Real-Time Torque Prediction for Grasping Unknown Objects with a Multi-Fingered Hand
When grasping objects with a multi-finger hand, it is crucial for the grasp stability to apply the correct torques at each joint so that external forces are countered. Most current systems use simple heuristics instead of modeling the required torque correctly. Instead, we propose a learning-based approach that is able to predict torques for grasps on unknown objects in real-time. The neural network, trained end-to-end using supervised learning, is shown to predict torques that are more efficient, and the objects are held with less involuntary movement compared to all tested heuristic baselines. Specifically, for 90 % of the grasps the translational deviation of the object is below 2.9 mm and the rotational below 3.1°. To generate training data, we formulate the analytical computation of torques as an optimization problem and handle the indeterminacy of multi-contacts using an elastic model. We further show that the network generalizes to predict torques for unknown objects on the real robot system with an inference time of 1.5 ms
Self-Contained Calibration of an Elastic Humanoid Upper Body with a Single Head-Mounted RGB Camera
When a humanoid robot performs a manipulation task, it
first makes a model of the world using its visual sensors
and then plans the motion of its body in this model. For
this, precise calibration of the camera parameters and the
kinematic tree is needed. Besides the accuracy of the
calibrated model, the calibration process should be fast
and self-contained, i.e., no external measurement equipment
should be used. Therefore, we extend our prior work on
calibrating the elastic upper body of DLR's Agile Justin by
now using only its internal head-mounted RGB camera. We use
simple visual markers at the ends of the kinematic chain
and one in front of the robot, mounted on a pole, to get
measurements for the whole kinematic tree. To ensure that
the task-relevant cartesian error at the end-effectors is
minimized, we introduce virtual noise to fit our imperfect
robot model so that the pixel error has a higher weight if
the marker is further away from the camera. This correction
reduces the cartesian error by more than 20%, resulting in
a final accuracy of 3.9mm on average and 9.1mm in the worst
case. This way, we achieve the same precision as in our
previous work, where an external cartesian tracking system
was used
A Two-Stage Learning Architecture That Generates High-Quality Grasps for a Multi-Fingered Hand
In this work, we investigate the problem of planning stable grasps for object manipulations using an 18-DOF robotic hand with four fingers. The main challenge here is the high-dimensional search space, and we address this problem using a novel two-stage learning process. In the first stage, we train an autoregressive network called the hand-pose-generator, which learns to generate a distribution of valid 6D poses of the palm for a given volumetric object representation. In the second stage, we employ a network that regresses 12D finger positions and scalar grasp qualities from given object representations and palm poses. To train our networks, we use synthetic training data generated by a novel grasp planning algorithm, which also proceeds stage-wise: first the palm pose, then the finger positions. Here, we devise a Bayesian Optimization scheme for the palm pose and a physics-based grasp pose metric to rate stable grasps. In experiments on the YCB benchmark data set, we show a grasp success rate of over 83%, as well as qualitative results on real scenarios of grasping unknown objects
First-in-human phase I/II, open-label study of the anti-OX40 agonist INCAGN01949 in patients with advanced solid tumors
Inmunomodulación; Linfocitos T; Microambiente tumoralImmunomodulació; Limfòcits T; Microambient tumoralImmunomodulation; T-Lymphocytes; Tumor microenvironmentBackground OX40 is a costimulatory receptor upregulated on antigen-activated T cells and constitutively expressed on regulatory T cells (Tregs). INCAGN01949, a fully human immunoglobulin G1κ anti-OX40 agonist monoclonal antibody, was designed to promote tumor-specific immunity by effector T-cell activation and Fcγ receptor-mediated Treg depletion. This first-in-human study was conducted to determine the safety, tolerability, and preliminary efficacy of INCAGN01949.
Methods Phase I/II, open-label, non-randomized, dose-escalation and dose-expansion study conducted in patients with advanced or metastatic solid tumors. Patients received INCAGN01949 monotherapy (7–1400 mg) in 14-day cycles while deriving benefit. Safety measures, clinical activity, pharmacokinetics, and pharmacodynamic effects were assessed and summarized with descriptive statistics.
Results Eighty-seven patients were enrolled; most common tumor types were colorectal (17.2%), ovarian (8.0%), and non-small cell lung (6.9%) cancers. Patients received a median three (range 1–9) prior therapies, including immunotherapy in 24 patients (27.6%). Maximum tolerated dose was not reached; one patient (1.1%) receiving 350 mg dose reported dose-limiting toxicity of grade 3 colitis. Treatment-related adverse events were reported in 45 patients (51.7%), with fatigue (16 (18.4%)), rash (6 (6.9%)), and diarrhea (6 (6.9%)) being most frequent. One patient (1.1%) with metastatic gallbladder cancer achieved a partial response (duration of 6.3 months), and 23 patients (26.4%) achieved stable disease (lasting >6 months in one patient). OX40 receptor occupancy was maintained over 90% among all patients receiving doses of ≥200 mg, while no treatment-emergent antidrug antibodies were detected across all dose levels. Pharmacodynamic results demonstrated that treatment with INCAGN01949 did not enhance proliferation or activation of T cells in peripheral blood or reduce circulating Tregs, and analyses of tumor biopsies did not demonstrate any consistent increase in effector T-cell infiltration or function, or decrease in infiltrating Tregs.
Conclusion No safety concerns were observed with INCAGN01949 monotherapy in patients with metastatic or advanced solid tumors. However, tumor responses and pharmacodynamic effects on T cells in peripheral blood and post-therapy tumor biopsies were limited. Studies evaluating INCAGN01949 in combination with other therapies are needed to further evaluate the potential of OX40 agonism as a therapeutic approach in patients with advanced solid tumors.This study was funded by Incyte Corporation (Wilmington, USA)
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The Aerosol Deposition Method: A Modified Aerosol Generation Unit to Improve Coating Quality
Owing to its ability to produce dense thick-films at room temperature directly from a ceramic powder, the Aerosol Deposition Method (AD) possesses a unique feature in ceramics processing. For this technology, the aerosol generation of particles is a decisive part of reliable process control. However, there has only been a small amount of work published addressing this topic. In this work, we compare the aerosolization and deposition behavior of a fluidized bed generator with an aerosol generator with the rotary brush principle. While film properties very much depend on deposition time for the fluidized bed generator, films produced with the brush generator show a constant film profile, and their film thickness correlates with the controllable aerosol concentration and the duration of deposition. This type of aerosol generation may improve the setup towards a more reliable AD process
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A New CYP2E1 Inhibitor, 12-Imidazolyl-1-dodecanol, Represents a Potential Treatment for Hepatocellular Carcinoma
Cytochrome P450 2E1 (CYP2E1) is a key target protein in the development of alcoholic and nonalcoholic fatty liver disease (FLD). The pathophysiological correlate is the massive production of reactive oxygen species. The role of CYP2E1 in the development of hepatocellular carcinoma (HCC), the final complication of FLD, remains controversial. Specifically, CYP2E1 has not yet been defined as a molecular target for HCC therapy. In addition, a CYP2E1-specific drug has not been developed. We have already shown that our newly developed CYP2E1 inhibitor 12-imidazolyl-1-dodecanol (I-ol) was therapeutically effective against alcoholic and nonalcoholic steatohepatitis. In this study, we investigated the effect of I-ol on HCC tumorigenesis and whether I-ol could serve as a possible treatment option for terminal-stage FLD. I-ol exerted a very highly significant antitumour effect against hepatocellular HepG2 cells. Cell viability was reduced in a dose-dependent manner, with only the highest doses causing a cytotoxic effect associated with caspase 3/7 activation. Comparable results were obtained for the model colorectal adenocarcinoma cell line, DLD-1, whose tumorigenesis is also associated with CYP2E1. Transcriptome analyses showed a clear effect of I-ol on apoptosis and cell-cycle regulation, with the increased expression of p27Kip1 being particularly noticeable. These observations were confirmed at the protein level for HepG2 and DLD-1 cells grafted on a chorioallantoic membrane. Cell-cycle analysis showed a complete loss of proliferating cells with a simultaneous increase in S-phase arrest beginning at a threshold dose of 30 μM. I-ol also reduced xenograft tumour growth in nude mice. This antitumour effect was not associated with tumour cachexia. I-ol was not toxic to healthy tissues or organs. This study demonstrates for the first time the therapeutic effect of the specific CYP2E1 inhibitor I-ol on the tumorigenesis of HCC. Our findings imply that I-ol can potentially be applied therapeutically on patients at the final stage of FLD. © 2021 Torsten Diesinger et al
Disturbed Placental Imprinting in Preeclampsia Leads to Altered Expression of DLX5, a Human-Specific Early Trophoblast Marker.
Background -Preeclampsia (PE) is a complex and common human-specific pregnancy syndrome associated with placental pathology. The human-specificity provides both intellectual and methodological challenges, lacking a robust model system. Given the role of imprinted genes in human placentation and the vulnerability of imprinted genes to loss of imprinting changes, there has been extensive speculation, but no robust evidence, that imprinted genes are involved in PE. Our study aims at investigating whether disturbed imprinting contributes to PE. Methods -We first aimed at confirming that PE is a disease of the placenta by generating and analysing genome-wide molecular data on well-characterized patient material. We performed high-throughput transcriptome analyses of multiple placenta samples from normal and PE patients. Next, we identified differentially expressed genes (DEGs) in PE placenta, and intersected them with the list of human imprinted genes. We employed bioinformatics/statistical analyses to confirm association between imprinting and PE, and to predict biological processes affected in PE. Validation included epigenetic and cellular assays. Regarding human-specificity, we established an in vitro invasion-differentiation trophoblast model. Our comparative phylogenetic analysis involved single-cell transcriptome data of human, macaque and mouse preimplantation embryogenesis. Results -We found disturbed placental imprinting in PE and revealed potential candidates, including GATA3 and DLX5, with poorly explored imprinted status and no prior association with PE. Due to loss of imprinting DLX5 was upregulated in 69% of PE placentas. Levels of DLX5 correlated with classical PE marker. DLX5 is expressed in human, but not in murine trophoblast. The DLX5(high) phenotype resulted in reduced proliferation, increased metabolism and ER stress-response activation in trophoblasts in vitro The transcriptional profile of such cells mimics the transcriptome of PE placentas. Pan-mammalian comparative analysis identified DLX5 as a part of the human-specific regulatory network of trophoblast differentiation. Conclusions -Our analysis provides evidence of a true association between disturbed imprinting, gene expression and PE. Due to disturbed imprinting, the upregulated DLX5 affects trophoblast proliferation. Our in vitro model might fill a vital niche in PE research. Human-specific regulatory circuitry of DLX5 might help to explain certain aspects of PE
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