The simultaneous localization and mapping (SLAM):An overview

Positioning is a need for many applications related to mapping and navigation either in civilian or military domains. The significant developments in satellite-based techniques, sensors, telecommunications, computer hardware and software, image processing, etc. positively influenced to solve the positioning problem efficiently and instantaneously. Accordingly, the mentioned development empowered the applications and advancement of autonomous navigation. One of the most interesting developed positioning techniques is what is called in robotics as the Simultaneous Localization and Mapping SLAM. The SLAM problem solution has witnessed a quick improvement in the last decades either using active sensors like the RAdio Detection And Ranging (Radar) and Light Detection and Ranging (LiDAR) or passive sensors like cameras. Definitely, positioning and mapping is one of the main tasks for Geomatics engineers, and therefore it's of high importance for them to understand the SLAM topic which is not easy because of the huge documentation and algorithms available and the various SLAM solutions in terms of the mathematical models, complexity, the sensors used, and the type of applications. In this paper, a clear and simplified explanation is introduced about SLAM from a Geomatical viewpoint avoiding going into the complicated algorithmic details behind the presented techniques. In this way, a general overview of SLAM is presented showing the relationship between its different components and stages like the core part of the front-end and back-end and their relation to the SLAM paradigm. Furthermore, we explain the major mathematical techniques of filtering and pose graph optimization either using visual or LiDAR SLAM and introduce a summary of the deep learning efficient contribution to the SLAM problem. Finally, we address examples of some existing practical applications of SLAM in our reality

Selective lactase deficiency is common in pediatric patients undergoing upper endoscopy

Lactase deficiency can lead to significant symptoms in the pediatric population. To date, few studies have examined the prevalence of enzyme testing-based lactase and other disaccharidase deficiencies (DDs) in pediatric patients undergoing upper endoscopic evaluation. The primary objective of this study was to determine the prevalence of selective lactase and other DDs amongst a large cohort of pediatric patients with and without inflammatory bowel disease (IBD: Crohn’s disease and ulcerative colitis) via a chart review of 739 patients who underwent esophago-gastro-dudenoscopy EGD between April 2010 and August 2016. We identified 560 pediatric patients (ages 1-18 years) who underwent mucosal enzyme testing at the time of their EGD. The overall rate of lactase deficiency (LD) was 39%. LD positively correlated with age (p=0.00017), but there was no significant difference between age matched IBD and non-IBD patients (45% vs. 42% p=0.68). Four patients (0.17%) were found to have selective maltase deficiency. No selective sucrase or palatinase deficiency was identified. Statistically significant differences occurred in lactase deficiency amongst patients of different races. In conclusion, lactase deficiency is a relatively common finding in children undergoing EGD though at no increased rate amongst the IBD patient population. Disaccharidase testing should be considered in pediatric patients undergoing EGD

Polycystic Liver With Cardiac Compression Leading to Atrial Fibrillation: Case Report and Review of the Literature.

Polycystic liver disease (PCLD) is a rare condition that most often occurs in patients with polycystic kidney disease and less commonly as an isolated liver disease. Complications include cyst rupture, infection, hemorrhage, and compression of surrounding organs by large cysts. We present the case of a patient with a history of PCLD who presented to our hospital with palpitations and was found to have atrial fibrillation. Imaging and echocardiograph revealed a dominant large cyst compressing the right atrium. Other etiologies including thyroid disease, ischemic heart disease, and electrolytes abnormalities were excluded. The patient refused surgical intervention and was conservatively treated with rate control and anticoagulation. To the best of our knowledge, this is the first case of new-onset atrial fibrillation secondary to right atrial compression by a liver cyst. Compression of cardiac chambers resulting in new-onset arrhythmia should be considered when evaluating patients with PCLD

Capim-colonião e seus efeitos sobre o crescimento inicial de clones de Eucalyptus x urograndis.

Esta pesquisa teve o objetivo de avaliar o efeito da convivência de capim-colonião sobre o crescimento inicial de plantas de clones de eucalipto. Foram instalados dois ensaios com mudas de clones de eucalipto e de capim-colonião, que cresceram em parcelas delimitadas lateralmente por paredes de alvenaria preenchidas com terra. O primeiro ensaio obedeceu ao delineamento experimental inteiramente casualizado, com três repetições, e tratamentos em esquema fatorial 5 x 2 (cinco clones de eucalipto, e a ausência ou presença de duas plantas de capim-colonião plantadas a 10 cm da muda de eucalipto). O segundo ensaio foi semelhante ao primeiro, porém, com apenas três clones de eucalipto, cinco repetições, e tratamentos em esquema fatorial 3 x 2 (três clones de eucalipto e a ausência ou presença de capim-colonião). Os clones de eucalipto não afetaram de modo diferenciado o crescimento de capim-colonião, sendo que aqueles que conviveram com a planta daninha não apresentaram diferença no seu desenvolvimento, igualando-os quando sob competição. As características dos clones de eucalipto mais sensíveis à convivência com capim-colonião foram: área foliar, matéria seca de folhas e caule. O clone 3 foi o que se mostrou mais sensível à convivência com capim-colonião e o clone 1 mais tolerante, porém todos os clones estudados tiveram influência negativa da convivência com capim-colonião

Periprosthetic joint infection increases the risk of one-year mortality.

BACKGROUND: Periprosthetic joint infection continues to potentially complicate an otherwise successful joint replacement. The treatment of this infection often requires multiple surgical procedures associated with increased complications and morbidity. This study examined the relationship between periprosthetic joint infection and mortality and aimed to determine the effect of periprosthetic joint infection on mortality and any predictors of mortality in patients with periprosthetic joint infection. METHODS: Four hundred and thirty-six patients with at least one surgical intervention secondary to confirmed periprosthetic joint infection were compared with 2342 patients undergoing revision arthroplasty for aseptic failure. The incidence of mortality at thirty days, ninety days, one year, two years, and five years after surgery was assessed. Multivariate analysis was used to assess periprosthetic joint infection as an independent predictor of mortality. In the periprosthetic joint infection population, variables investigated as potential risk factors for mortality were evaluated. RESULTS: Mortality was significantly greater (p \u3c 0.001) in patients with periprosthetic joint infection compared with those undergoing aseptic revision arthroplasty at ninety days (3.7% versus 0.8%), one year (10.6% versus 2.0%), two years (13.6% versus 3.9%), and five years (25.9% versus 12.9%). After controlling for age, sex, ethnicity, number of procedures, involved joint, body mass index, and Charlson Comorbidity Index, revision arthroplasty for periprosthetic joint infection was associated with a fivefold increase in mortality compared with revision arthroplasty for aseptic failures. In the periprosthetic joint infection population, independent predictors of mortality included increasing age, higher Charlson Comorbidity Index, history of stroke, polymicrobial infections, and cardiac disease. CONCLUSIONS: Although it is well known that periprosthetic joint infection is a devastating complication that severely limits joint function and is consistently difficult to eradicate, surgeons must also be cognizant of the systemic impact of periprosthetic joint infection and its major influence on fatal outcome in patients