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Communication connectivity is desirable for the safe and efficient operation of multi-robot systems. While decentralized algorithms for connectivity maintenance have been explored in recent literature, the majority of these works do not account for robot motion and sensing uncertainties. These uncertainties are inherent in practical robots and result in robots deviating from their desired positions which could potentially result in a loss of connectivity. In this paper, we present a decentralized connectivity maintenance algorithm accounting for robot motion and sensing uncertainties (DCMU). We, first, propose a novel weighted graph definition for the multi-robot system that accounts for the aforementioned uncertainties along with realistic connectivity constraints such as line-of-sight connectivity and collision avoidance. We, then, design a decentralized gradient-based controller for connectivity maintenance with which we derive the gradients of the weighted graph edge weights required for computing the control. Finally, we perform multiple simulations to validate the connectivity maintenance performance of our DCMU algorithm under robot motion and sensing uncertainties, showing an improvement compared to previous work. [ABSTRACT FROM AUTHOR]

Background: Delayed presentation of pelvic-acetabular fractures is a common scenario in developing countries and there is usually a delay of more than 24 h in their presentation.Objectives: We aim to comparatively analyse early(<24 h) versus delayed (>24 h) thromboprophylaxis with low molecular weight heparin (LMWH) in prevention of deep venous thrombosis (DVT) in Pelvic Acetabular fractures.Methods: Patients of pelvic-acetabular fractures who presented during 1 year of study period were divided into 2 groups after exclusion of patients with contraindications for thromboprophylaxis. Group A included patients who received LMWH prophylaxis within 24 h of injury. Group B included patients who received LMWH prophylaxis after 24 h of injury. All patients underwent CT venography at day 14 and were followed up with doppler ultrasound on 4th and 8th week.Results: 110 patients with pelvic-acetabular fractures were included after exclusion of 61 patients. 4 out of 29 patients in group A (13.8%) and 12 out of 81 patients (14.8%) in group B developed DVT. There was no significant difference in incidence of DVT between Group A and B (P value-0.893).Conclusion: There was no difference between early and delayed thromboprophylaxis with LMWH in pelvic-acetabular trauma. [ABSTRACT FROM AUTHOR]

To protect civilian Global Positioning System (GPS) users from spoofing, the Air Force Research Lab has developed the chips-message robust authentication (Chimera) signal enhancement for the GPS L1C signal. With Chimera, standalone receivers that only have access to the GPS signal will be able to authenticate their received measurements once every 3 min, whereas users with access to an out-of-band source will be able to perform authentication once every 1.5 or 6 s. However, moving receivers typically rely on much faster real-time GPS update rates of 1-20 Hz. In this work, we design a spoofing-resilient filter framework that provides continuous and secure state estimation between Chimera authentication times. By leveraging self-contained sensors on-board the vehicle, such as an inertial measurement unit or wheel encoder, as well as the periodic Chimera authentication, our proposed filter determines how much to rely on the received unauthenticated GPS measurements for state estimation. In this respect, our filter relies more extensively on GPS measurements in order to improve real-time navigation performance and reduce localization errors when GPS signals are authentic, while successfully mitigating spoofing-induced errors during an experienced attack. We experimentally validate our proposed spoofing-resilient filter in a simulated test environment for a ground vehicle model with access to the 3-min Chimera channel, under various simulated spoofing attack scenarios. To the best of the authors' knowledge, this is the first adaptive filter proposed for Chimera that continuously leverages real-time GPS measurements in a spoofing-resilient manner. [ABSTRACT FROM AUTHOR]

Outdoor positioning for unmanned aerial vehicles (UAVs) commonly relies on global navigation satellite system (GNSS) signals, which might be reflected or blocked in urban areas. Thus, additional on‐board sensors such as light detection and ranging (LiDAR) are desirable to aid positioning. To fuse measurements from different sensors, it is important to accurately characterize the error covariance matrices of individual sensor measurements. We propose a novel method for adaptively estimating the LiDAR‐based positioning error covariance matrix based on the point cloud features surrounding the UAV. We model the position error as a multivariate Gaussian distribution and estimate its covariance matrix from individual surface and edge feature points. Simulations show that our model is more accurate than a distance‐based covariance matrix model. Furthermore, we conduct an outdoor experiment that fuses global positioning system (GPS) signals and LiDAR position measurements. We demonstrate a clear improvement in the UAV's global position estimation using our adaptive covariance matrix for LiDAR‐based measurements. [ABSTRACT FROM AUTHOR]

As the demand for liver transplantation continues to rise, the scarcity of liver donor grafts has led to the use of extended criteria grafts for liver transplantation in select group of patients. Hepatitis C-seropositive liver grafts have been used primarily in hepatitis C-positive recipients, with studies showing non-inferior outcomes when compared to hepatitis C-negative grafts. Studies suggest that hepatitis C serology status of the donor liver does not influence the patient or graft outcomes in the recipient. These results advocate for offering hepatitis C-positive grafts to all patients awaiting liver transplantation regardless of their hepatitis C status. However, some concerns persist regarding the ethics of potentially introducing a new infection into a patient that could progress to chronic liver disease following liver transplantation. The recent approval of direct-acting antiviral therapy offers a solution to this dilemma, as it has changed the landscape of hepatitis C management by making it a curable disease. In this review, we shall discuss the current evidence regarding the use of hepatitis C-seropositive donor grafts in hepatitis C-positive and hepatitis C-negative patients. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in industrialized nations and is strongly associated with the metabolic syndrome. The prevalence of NAFLD continues to rise along with the epidemic of the metabolic syndrome. Metabolic homeostasis is linked to the circadian clock (rhythm), with multiple signaling pathways in organs regulated by circadian clock genes, and recent studies of circadian clock gene functions suggest that disruption of the circadian rhythm is associated with significant morbidity and mortality, including the metabolic syndrome. In the industrialized world, various human behaviors and activities such as work and eating patterns, jet lag, and sleep deprivation interfere with the circadian rhythm, leading to perturbations in metabolism and development of the metabolic syndrome. In this review, we discuss how disruption of the circadian rhythm is associated with various metabolic conditions that comprise the metabolic syndrome and NAFLD. [ABSTRACT FROM AUTHOR]

Background: Removal of impacted third molars is the most common oral surgical procedure. Many investigators have questioned the necessity of removal in patients who are free of symptoms or associated pathologies. Aim: The aim of this retrospective study was to evaluate the incidence of caries on distal aspect of mandibular second molars in patients referred for corresponding third molar assessment and to identify its association with angular position and depth of the impacted mandibular third molars based on the classification of Pell and Gregory. Methodology: Records of 150 patients with impacted third molar presenting to the Department of Oral and Maxillofacial Surgery, Sri Rajiv Gandhi College of Dental Sciences and Hospital, were assessed retrospectively. The radiographic angulation and depth of mandibular third molar impaction were determined and compared to determine the relationship with incidence of caries on the distal surface of the second molar. Results: According to this study results, 37.5% cases show caries on the distal aspect of mandibular second molars. The incidence of caries with mesioangular impacted third molars was 55%. A majority of these mesioangular cases were Level B and Class I as per the Pell and Gregory classification. Conclusion: The prophylactic extraction of mandibular third molars is indicated if the angulation is between 30° and 70° and is justified by incidence of distal caries in the second molars. [ABSTRACT FROM AUTHOR]

The electric utility industry currently offers a wide array of attractive investment opportunities. Each investor must sort through the multitude of potential investments to focus on those that best match its own risk, return, and strategic profile. Here are some basic principles worth following. [Copyright &y& Elsevier]

Cholangiocarcinoma is a tumor that arises as a result of differentiation of the cholangiocytes and can develop from anywhere in the biliary tree. Subtypes of cholangiocarcinoma are differentiated based on their location in the biliary tree. If diagnosed early these can be resected, but most cases of intrahepatic cholangiocarcinoma present late in the disease course where surgical resection is not an option. In these patients who are poor candidates for resection, a combination of chemotherapy, locoregional therapies like ablation, transarterial chemo and radioembolization, and in very advanced and metastatic disease, external radiation are the available options. These modalities can improve overall disease-free and progression-free survival chances. In this review, we will discuss the risk factors and clinical presentation of intrahepatic cholangiocarcinoma, diagnosis, available therapeutic options, and future directions for management options. [ABSTRACT FROM AUTHOR]

The article focuses on the interactive learning board game called Circles of Care, which was created by seven students from the University of Western Ontario in Canada. It says that four to eight players composed of healthcare students and professionals can play the game, in which each team will spin a wheel and given an assigned patient booklet. It also mentions that each of the 12 booklets contain set of questions in four different ways.

The article informs about Management of Orthopaedic Patients During COVID‑19 Pandemic in India. Topics discussed include hospitals are becoming hot zones for the treatment as well as transmission of COVID-19 due to a rise in the community transmission from Europe; and orthopaedic surgeries including both elective and emergency procedures require operation theatres which are high-risk areas for transmission of COVID-19.

INTRODUCTION: In the published studies of early liver transplantation (LT) for alcohol-associated hepatitis (AH), patients with a prior liver decompensation are excluded. The appropriateness of this criteria is unknown. Methods: Among 6 American Consortium of Early Liver Transplantation for Alcohol-Associated Hepatitis sites, we included consecutive early LT for clinically diagnosed AH between 2007 and 2020. Patients were stratified as first vs prior history of liver decompensation, with the latter defined as a diagnosis of ascites, hepatic encephalopathy, variceal bleeding, or jaundice, and evidence of alcohol use after this event. Adjusted Cox regression assessed the association of first (vs prior) decompensation with post-LT mortality and harmful (i.e., any binge and/or frequent) alcohol use. Results: A total of 241 LT recipients (210 first vs 31 prior decompensation) were included: median age 43 vs 38 years (P = 0.23), Model for End-Stage Liver Disease Sodium score of 39 vs 39 (P = 0.98), and follow-up after LT 2.3 vs 1.7 years (P = 0.08). Unadjusted 1- and 3-year survival among first vs prior decompensation was 93% (95% confidence interval [CI] 89%–96%) vs 86% (95% CI 66%–94%) and 85% (95% CI 79%–90%) vs 78% (95% CI 57%–89%). Prior (vs first) decompensation was associated with higher adjusted post-LT mortality (adjusted hazard ratio 2.72, 95% CI 1.61–4.59) and harmful alcohol use (adjusted hazard ratio 1.77, 95% CI 1.07–2.94). DISCUSSION: Prior liver decompensation was associated with higher risk of post-LT mortality and harmful alcohol use. These results are a preliminary safety signal and validate first decompensation as a criterion for consideration in early LT for AH patients. However, the high 3-year survival suggests a survival benefit for early LT and the need for larger studies to refine this criterion. These results suggest that prior liver decompensation is a risk factor, but not an absolute contraindication to early LT. [ABSTRACT FROM AUTHOR]

Mucormycosis is caused by ubiquitous fungi and encompasses a variety of different opportunistic syndromes in humans that disproportionately affect immunocompromised patients. Mortality has been documented to range between 50 and 100%; however, location of infection greatly dictates likelihood of survival. Treatment of mucormycosis involves aggressive surgical intervention and combination therapy of antifungal agents. In solid organ transplant recipients, immunosuppressive agents used to prevent rejection of the transplanted organ pose additional obstacles in the treatment of invasive fungal infections. We report on 3 high models for end-stage liver disease (MELD-Na) score orthotopic liver transplant (OLT) recipients who all were diagnosed with Rhizopus spp. infections with positive, 1-year outcomes after aggressive, individualized treatment. [ABSTRACT FROM AUTHOR]

Introduction: Extra-articular proximal tibia fractures make up to one-tenth of all tibia shaft fractures. Treatment options include conservative, nailing, plating and external fixation. There is no consensus on which method is superior if the patient is to be managed surgically. Materials and Methods: We conducted a systematic review and meta-analysis to know which definitive surgical treatment option (nailing or plating) is better for extra-articular proximal tibia fracture. We used search engines like PubMed, Embase, Scopus, Ovid Medline and Google Scholar to find articles comparing the results of nailing versus plating. We could identify only 4 articles regarding this and data was extracted and meta-analysis was done. Results: Delayed union was common in the nailing group with odds ratio of 8.29 favoring the plating group (95% CI 1.77, 38.80, p = 0.007) while malunion showed no difference in both groups. Rate of infection was higher in the plating group while anterior knee pain was common in the nailing group with odds ratio of 5.54 favoring the plating group (95% CI 1.49, 13.88, p = 0.008). Range of motion showed no difference between both groups, fractures in the nailing group united early and the difference was significant (p = 0.005, odds ratio – 4.48) (95% CI – 8.29, – 1.47).The surgical duration was less in the nailing group but was not significant. Conclusion: Considering lesser time for union, early weight bearing, lower chances of infection and lesser surgical duration, nailing seems to be more promising for extra articular proximal tibia fractures. Further research is required on this topic to provide a definitive evidence. [ABSTRACT FROM AUTHOR]

Background: Orthopaedic residency training is a 3-year period of preparation that converts a raw medical student into a proficient orthopaedic surgeon. Due to wide variations at different centers in India, the program in a tertiary hospital is presented, in an attempt to improve the overall levels of training. Materials and Methods: PGIMER has produced many good surgeons who are well settled across the country and the world. A survey of the postgraduates of the last 30 years was done to highlight the perceptions about the program. An overview of the program was also added to the narrative to highlight the positive aspects of the training. Results: 132 Orthopaedic passed-out residents from PGIMER could be contacted. 97% of them rated their residency experience as excellent or good, and stated that they would recommend this program to new residents. Key points highlighted by them were the readiness of trainees for any surgical contingency after graduation, continuation of the mindset for research, and their prompt acceptability into their subsequent places of work due to their place of graduation. Discussion: Converting an orthopaedic resident into a competent surgeon involves knowledge upgrades and impartation of skills; these are not limited to the theory of orthopaedics, but involve the thought processes and the planning as a surgeon, the attitude towards patient management, and a continuously inquisitive scientific mind. The shortcomings and strengths of the residency program in PGIMER are discussed; international standard methodology limited to this institute like formal log books, mentorship program, hands-on skill development through courses, etc. is something that is recommended to be mandatory in all residency programs. Conclusion: The PGIMER Orthopaedic residency program could act as a basic model for other Indian medical schools, with any appropriate modifications. Standardization of Orthopaedic residency programs could allow upgrading to International levels. [ABSTRACT FROM AUTHOR]

Simple Summary: Transplant oncology is an emerging concept of cancer treatment with a promising prospective outcome. The application of oncology, transplant medicine, and surgery to improve patients' survival and quality of life is the core of transplant oncology. This review illustrates the concept and history of transplant oncology as an evolving field for the management of hepatocellular carcinoma, intrahepatic biliary cancer, and liver-only metastasis of non-hepatobiliary carcinoma. The utility of immunotherapy in the transplant setting is discussed as well as the feasibility of using circulating tumor DNA for surveillance post-transplantation. As transplant oncology continues to evolve as a promising field in cancer management, it is expected that there will be improved outcomes and expansion of transplant eligibility through the consolidation of multidisciplinary and collaborative efforts. Liver transplantation is increasingly associated with improved survival outcomes in patients with liver malignancies. Eligibility criteria for liver transplantation has expanded over the years to include more patients with cancer. In addition, immunotherapy and ctDNA are two emerging concepts that are highly applicable to transplant oncology treatment. Immunotherapy may be used as neoadjuvant "bridging" therapy pre- liver transplantation and possibly in the palliative setting post-transplantation. Liquid biopsy to assess ctDNA post-transplantation can potentially be used as a biomarker to detect minimal residual disease and disease recurrence. Transplant oncology is an emerging concept of cancer treatment with a promising prospective outcome. The application of oncology, transplant medicine, and surgery to improve patients' survival and quality of life is the core of transplant oncology. Hepatobiliary malignancies have been treated by liver transplantation (LT) with significant improved outcome. In addition, as the liver is the most common site of metastasis for colorectal cancer (CRC), patients with CRC who have stable unresectable liver metastases are good candidates for LT, and initial studies have shown improved survival compared to palliative systemic therapy. The indications of LT for hepatobiliary malignancies have been slowly expanded over the years in a stepwise manner; however, they have only been shown to improve patient survival in the setting of limited systemic therapy options. This review illustrates the concept and history of transplant oncology as an evolving field for the management of hepatocellular carcinoma, intrahepatic biliary cancer, and liver-only metastasis of non-hepatobiliary carcinoma. The utility of immunotherapy in the transplant setting is discussed as well as the feasibility of using circulating tumor DNA for surveillance post-transplantation. [ABSTRACT FROM AUTHOR]

Management of large cystic lesion requires a multidisciplinary approach. In this case report a large radicular cyst is managed by conventional root canal treatment with triple antibiotic paste followed by surgical enucleation. In this case, patient presented with a 4 cm symptomatic swelling of the palate adjacent to teeth 21, 22 and 23. The swelling was soft on palpation and the overlying mucosa was of normal color. Radiographically, a well-defined unilocular radiolucency with corticated margins was seen. A full-thickness flap was reflected and revealed a large cyst-like lesion that had perforated the lingual cortical plate. The lesion was enucleated and submitted for microscopic examination. The biopsy report confirmed the diagnosis as radicular cyst. The patient was recalled after 6 months, and no symptoms or signs were noted. Radiograph showed the healing lesion. [ABSTRACT FROM AUTHOR]