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My first ever "painting" was a copy of my grandfather's painting of Kashmir. Charcoal and pastel on rice paper 11 × 8 in. Courtesy of the artist and Chatterjee & Lal PHOTO (COLOR): Nikhil Chopra (b. 1974) Lands, Waters & Skies: Sundersar, 2018. Could you describe the paintings of your grandfather and your memories of Kashmir? It's quite a dark song, and I sing it in the Sackler wing, with the projections of archival footage of America, museums, and institutional Met museum people, in Egypt in the early part of the twentieth century, digging graves in Egypt, excavating priceless pieces from burial sites. [Extracted from the article]

Images courtesy Chatterjee & Lal and the artist PHOTO (COLOR): Performance Lands, Waters and Skies by Nikhil Chopra, Metropolitan Museum of Art, New York. Images courtesy Chatterjee & Lal, Galleria Continua and the artist PHOTO (COLOR): Performance Drawing a Line through Landscape by Nikhil Chopra, documenta 14, 2017. Images courtesy Chatterjee & Lal, Galleria Continua and the artist PHOTO (COLOR): Performance Drawing a Line through Landscape by Nikhil Chopra, documenta 14, 2017. Images courtesy Chatterjee & Lal, Galleria Continua and the artist PHOTO (COLOR): Performance Lands, Waters and Skies by Nikhil Chopra, Metropolitan Museum of Art, New York. [Extracted from the article]

In this brief, false data injection attacks in bilateral teleoperation systems (BTOSs) are studied, where the attacker can inject false data into the states being exchanged between the master and slave robots. To demonstrate the vulnerability of BTOS, a destabilizing false data injection attack (DFDIA) is designed and experimentally implemented. To detect any general false data injection attack, including DFDIA as a special case, a physics-based detection scheme with an encoding–decoding structure is proposed. The efficacy of the proposed attack detection scheme is demonstrated in experiments. [ABSTRACT FROM AUTHOR]

Introduction: Laparoscopic ventral mesh rectopexy (LVMR) has gained widespread acceptance for the management of complete rectal prolapse (CRP). However, there have been concerns considering its use in patients with a redundant sigmoid colon. This study was conducted to evaluate the anatomical and functional results following LVMR, particularly in cases of CRP with a redundant sigmoid colon. Materials and Methods: Retrospective analysis of 25 patients who underwent LVMR from January 2011 to September 2016 was performed. Patients were divided into two groups according to the duration of follow-up. Group A (long-term) with follow-up >3 years and Group B (mid-term) <3 years. Results: The study included 25 patients (M:F = 1.5:1) with a median age of 38 years. Eighty-eight percent of the patients had a redundant sigmoid colon. Significant improvement in post-operative Wexner score as compared to pre-operative values was seen in patients with pre-existing constipation (P < 0.0001). In patients presenting with faecal incontinence (FI), significant improvement in post-operative St. Mark's incontinence score was observed. Functional outcomes remain consistent in long-term follow-up (>3 years). Conclusions: LVMR seems to be a feasible surgical procedure with minimum morbidity and good long-term functional outcomes. It provides satisfactory results in patients with redundant sigmoid colon and improves pre-existing constipation and FI. [ABSTRACT FROM AUTHOR]

Introduction: Most centres offer laparoscopic treatment for liver hydatid cyst (LHC). There have been concerns about the management of intra-peritoneal spillage, bleeding, and cystobiliary communication (CBC) during laparoscopic surgery for LHC. CBC can exist in 13%-37% of cases of LHC. No randomised studies have compared open versus laparoscopic approach for the treatment of LHC. We specifically analysed the outcomes of laparoscopic treatment of LHC with special reference to associated biliary complications. Patients and Methods: We analysed our prospectively collected data of patients undergoing laparoscopic treatment of LHC from 2009 to 2016. Patients undergoing open surgery or interventional radiology procedures were not included. Data analysed included demographic profile, investigational parameters, intra-operative findings and postoperative results with special reference to biliary complications and presence/management of CBC. Results: A total of 41 patients underwent laparoscopic treatment of LHC. History of jaundice was present in 5 (12.2%) patients. CBC was documented in 16 (39.02%) patients. In 11 patients, CBC was detected intra-operatively as visible communication, which was suture ligated or clipped. Five patients had occult CBC, detected as bile leak in the post-operative period. The leak resolved spontaneously in 7 patients and with biliary stenting in 2 patients. Only one patient had a persistent biliary leak. Postoperative bile leak was more common in patients with raised alkaline phosphatase. No statistically significant association was seen with size or location of the cyst, number of cysts and World Health Organisation classification. Conclusion: Laparoscopic treatment of LHC with associated CBC provides acceptable results. [ABSTRACT FROM AUTHOR]

Control technology is one of the fundamental disciplines of robotics. This special issue presents the recent theory and practice of control technology applied to networked and distributed robotics. [Extracted from the article]

In this paper, vulnerability of a distributed consensus seeking multi-agent system (MAS) with double-integrator dynamics against edge-bound content modification cyber attacks is studied. In particular, we define a specific edge-bound content modification cyber attack called malignant content modification attack (MCoMA), which results in unbounded growth of an appropriately defined group disagreement vector. Properties of MCoMA are utilized to design detection and mitigation algorithms so as to impart resilience in the considered MAS against MCoMA. Additionally, the proposed detection mechanism is extended to detect the general edge-bound content modification attacks (not just MCoMA). Finally, the efficacies of the proposed results are illustrated through numerical simulations. [ABSTRACT FROM AUTHOR]

In order to accomplish cooperative tasks, decentralized systems are required to communicate among each other. Thus, maintaining the connectivity of the communication graph is a fundamental issue. Connectivity maintenance has been extensively studied in the last few years, but generally considering undirected communication graphs. In this paper, we introduce a decentralized control and estimation strategy to maintain the strong connectivity property of directed communication graphs. In particular, we introduce a hierarchical estimation procedure that implements power iteration in a decentralized manner, exploiting an algorithm for balancing strongly connected directed graphs. The output of the estimation system is then utilized for guaranteeing preservation of the strong connectivity property. The control strategy is validated by means of analytical proofs and simulation results. [ABSTRACT FROM PUBLISHER]

In order to accomplish cooperative tasks, multi-robot systems are required to communicate among each other. This inter-robot communication can be modeled as a graph. Thus, maintaining the connectivity of the communication graph is a fundamental issue in cooperative robotic systems. Connectivity maintenance has been extensively studied in the last few years, but generally considering only kinematic agents. In this paper we introduce a control strategy which, by exploiting a decentralized procedure for the estimation of the algebraic connectivity of the graph, ensures connectivity maintenance for groups of Lagrangian systems. Collision avoidance control actions are also integrated with the connectivity maintenance algorithm. The control strategy is validated by means of analytical proofs and simulation results. [ABSTRACT FROM AUTHOR]