54 research outputs found

    Efficient Jacobian-Based Inverse Kinematics With Sim-to-Real Transfer of Soft Robots by Learning

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    This paper presents an efficient learning-based method to solve the inverse kinematic (IK) problem on soft robots with highly non-linear deformation. The major challenge of efficiently computing IK for such robots is due to the lack of analytical formulation for either forward or inverse kinematics. To address this challenge, we employ neural networks to learn both the mapping function of forward kinematics and also the Jacobian of this function. As a result, Jacobian-based iteration can be applied to solve the IK problem. A sim-to-real training transfer strategy is conducted to make this approach more practical. We first generate a large number of samples in a simulation environment for learning both the kinematic and the Jacobian networks of a soft robot design. Thereafter, a sim-to-real layer of differentiable neurons is employed to map the results of simulation to the physical hardware, where this sim-to-real layer can be learned from a very limited number of training samples generated on the hardware. The effectiveness of our approach has been verified on pneumatic-driven soft robots for path following and interactive positioning

    Somatostatin receptor-directed molecular imaging for therapeutic decision-making in patients with medullary thyroid carcinoma

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    BACKGROUND: Somatostatin receptor (SSTR) positron emission tomography/computed tomography (PET/CT) is increasingly deployed in the diagnostic algorithm of patients affected with medullary thyroid carcinoma (MTC). We aimed to assess the role of SSTR-PET/CT for therapeutic decision making upon restaging. METHODS: 23 pretreated MTC patients underwent SSTR-PET/CT and were discussed in our interdisciplinary tumor board. Treatment plans were initiated based on scan results. By comparing the therapeutic regimen before and after the scan, we assessed the impact of molecular imaging on therapy decision. SSTR-PET was also compared to CT portion of the SSTR-PET/CT (as part of hybrid imaging). RESULTS: SSTR-PET/CT was superior in 9/23 (39.1%) subjects when compared to conventional CT and equivalent in 14/23 (60.9%). Those findings were further corroborated on a lesion-based level with 27/73 (37%) metastases identified only by functional imaging (equivalent to CT in the remaining 46/73 (63%)). Investigating therapeutic decision making, no change in treatment was initiated after PET/CT in 7/23 (30.4%) patients (tyrosine kinase inhibitor (TKI), 4/7 (57.2%); surveillance, 3/7 (42.8%)). Imaging altered therapy in the remaining 16/23 (69.6%). Treatment prior to PET/CT included surgery in 6/16 (37.5%) cases, followed by TKI in 4/16 (25%), active surveillance in 4/16 (25%), and radiation therapy (RTx) in 2/16 (12.5%) subjects. After SSTR-PET/CT, the therapeutic regimen was changed as follows: In the surgery group, 4/6 (66.7%) patients underwent additional surgery, and 1/6 (16.7%) underwent surveillance and TKI, respectively. In the TKI group, 3/4 (75%) individuals received another TKI and the remaining subject (1/4, 25%) underwent peptide receptor radionuclide therapy. In the surveillance group, 3/4 (75%) underwent surgery (1/4, (25%), RTx). In the RTx group, one patient was switched to TKI and another individual was actively monitored (1/2, 50%, respectively). Moreover, in the 16 patients in whom treatment was changed by molecular imaging, control disease rate was achieved in 12/16 (75%) during follow-up. CONCLUSIONS: In patients with MTC, SSTR-PET/CT was superior to CT alone and provided relevant support in therapeutic decision-making in more than two thirds of cases, with most patients being switched to surgical interventions or systemic treatment with TKI. As such, SSTR-PET/CT can guide the referring treating physician towards disease-directed treatment in various clinical scenarios

    Immunohistochemical analysis of the antibodies PAT-SM6 and PAT-LM1 of colon cancer and the metastases

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    Das kolorektale Karzinom stellt die dritthäufigste Tumorerkrankung weltweit dar. Die Risikofaktoren sind vielseitig und werden in exogene und endogene Faktoren eingeteilt. Eine wichtige Präventionsmaßnahme von Kolonkarzinom ist die komplette endoskopische Koloskopie, die ab dem 55. Lebensjahr empfohlen wird. Der Goldstandard zur Behandlung von Kolonkarzinom ist nach wie vor die chirurgische Tumorresektion mit mikroskopisch nachgewiesener Tumorfreiheit. Eine chirurgische Sanierung der Fernmetastasen, welche am häufigsten in der Leber vorkommen, ist bei betroffenen Patienten anzustreben. Eine adjuvante Chemotherapie wird je nach UICC-Stadium des Tumors durchgeführt. Im Gegensatz zur Behandlung einiger maligner Tumorerkrankungen ist der Einsatz von Antikörpern noch kein fester Bestandteil der Therapie von Kolonkarzinomen. In dieser Arbeit wurde Untersuchungsmaterial von 41 Patienten mit Kolonkarzinom, die am Universitätsklinikum Würzburg in den Jahren 1997 bis 2012 behandelt wurden, analysiert. Dabei wurden Paraffinschnitte vom Primärtumor, regionalen Lymphknotenmetastasen und Lebermetastasen der einzelnen Patienten mit 2 verschiedenen monoklonalen IgM-Antikörpern, PAT-SM6 und PAT-LM1, gefärbt und mikroskopisch untersucht. Der Antikörper PAT-SM6 wurde aus einem an einem Magenkarzinom erkrankten Patienten isoliert und bindet an eine Isotyp-Form des 'Glucose-Regulated' Protein (GRP)-78PAT-SM6. Als Zielstruktur des PAT-LM1 Antikörpers wurde eine tumorspezifische Form von NONO (Non-POU domain-containing octamer-binding protein) identifiziert (NONOPAT-LM1). Für beide Rezeptor-Isoformen wurde nachgewiesen, dass sie nur auf malignen epithelialen Zellen, nicht aber auf gesunden Zellen exprimiert werden. Anhand dieser Arbeit konnte gezeigt werden, dass PAT-SM6 die Tumorzellen der Lebermetastasen stärker anfärbte als Zellen des Primärtumors. Für die PAT-LM1 Antikörperfärbung wurde ein ähnliches Resultat erzielt. In Bezug auf das Lebensalter der Patienten wiesen die Tumorzellen von älteren Patienten (ab dem 65. Lebensjahr) eine stärkere Antikörperbindung durch PAT-SM6 und PAT-LM1 auf. Interessant war auch die Feststellung, dass die Tumorzellen der Lebermetastasen von verstorbenen Patienten durch PAT-LM1 stärker gefärbt waren als die von zum Untersuchungszeitpunkt noch lebenden Patienten. Die Bindungsunterschiede zwischen PAT-SM6 und PAT-LM1 könnten neue diagnostische und therapeutische Möglichkeiten bei Kolonkarzinomen bieten und somit zukünftig eine individuelle Tumortherapie ermöglichen.Colorectal carcinoma is one of the most frequently malignant tumor disease worldwide. Two antibodies, PAT-SM6 and PAT-LM1 were used on primary tumor of colon cancer and metastases for the immunohistochemical analyses. It could been shown that both antibodies had a strong affinity to metastases and the tumorcells of older patients

    Effects of temperature parameters on thermal-optical analysis of organic and elemental carbon in aerosol

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    Il contributo si sofferma sull\u2019uso delle opere di Sabino nella giurisprudenza antoniniana, prendendo in considerazione, in particolare, la produzione scientifica di Giuliano, Pomponio, Venuleio, Gaio, Marcello e Scevola. Tutte le citazioni dei giuristi di et\ue0 antoniniana concernenti la produzione di Sabino sono prive di indicazioni relative al luogo in cui le opinioni tramandate sono state espresse, e, pertanto, inserite da Otto Lenel in un Index locorum, quibus non indicato libro aut Sabinus aut Sabiniani laudantur. Dall\u2019analisi delle fonti, emerge che i giuristi di et\ue0 antoniniana davano conto delle opinioni espresse da Sabino, non solo attingendo direttamente alla sua produzione, ma anche attraverso le opere dei suoi auditores, Gaio Cassio Longino, Minicio, Fufidio, Urseio Feroce.Der Beitrag befasst sich mit der Verwendung der Werke des Sabinus in der Zeit der Antoninen, wobei insbesondere auf die wissenschaftlichen Schriften von Julianus, Pomponius, Venuleius, Gaius, Marcellus und Scaevola eingegangen wird. Keines der die wissenschaftlichen Schriften des Sabinus betreffenden Zitate in der Zeit der Antoninen enth\ue4lt einen Hinweis darauf, wo die u\u308berlieferten Meinungen zum Ausdruck gebracht worden sind; sie wurden daher von Otto Lenel vorsichtshalber in einen Index locorum, quibus non indicato libro aut Sabinus aut Sabiniani laudantur eingetragen. Die Analyse der Quellen zeigt, dass die Juristen im Zeitalter der Antoninen die Meinungen Sabinus nicht nur direkt seinen Werken entnommen haben, sondern auch den Werken seiner auditores, Gaius Cassius Longinus, Minicius, Fufidius, Urseius Ferox

    Effects of temperature parameters on thermal-optical analysis of organic and elemental carbon in aerosol

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    Thermal-optical analysis (TOA) is a popular method to determine aerosol elemental carbon (EC) and organic carbon (OC) collected on quartz fiber filter. However, temperature protocol adopted in TOA has great effects on OC and EC results. The purpose of this study is to investigate and quantify the effects of maximum temperature (T (max) ) and residence time (RT) for each step in helium stage on ECOC measurements. Fourteen typical source samples and 20 ambient samples were collected and six temperature programs were designed for this study. It was found that EC value decreases regularly as T (max) ascends, i.e., EC results from T (max) of 650A degrees C, 750A degrees C and 850A degrees C are 0.89 +/- 0.06, 0.76 +/- 0.10, 0.62 +/- 0.13 times EC value from T (max) of 550A degrees C, respectively, and the magnitude of EC drop (EC (d) , percent) is significantly correlated with OC abundance in total carbon (R (OC/TC) ), expressed as EC (d) = 66.8R (OC/TC) - 14.4 (r = 0.87); pyrolized OC (POC) values are also sensitive to T (max) , but there are various trends for samples with different OC constituents. On average of the samples studied here, prolonged RT reduces EC values by only 3%, almost negligible compared to the effect of T (max) , and reduces POC by 9%, much less than that by previous report
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