Background
Laparoscopic technical surgical skills (LTS) are considered a fundamental competence for General Surgery residents. Several simulation tools (ST) have been explored to develop LTS. ...Although a plethora of systematic reviews evaluate the translation of LTS developed in simulation to real surgery, there is a lack of evidence that clarifies effectiveness of different validated ST in acquisition of LTS in surgical residents. The aim of this systematic review (SR) is to summarize published evidence on ST validation used for surgery education and training.
Methods
A protocol was published in PROSPERO. A SR was carried out following PRISMA guidelines. Complete published articles in English or Spanish that validate either content or construct, plus another form of validation of ST to acquire LTS in general surgery were included. Articles that used only one validation or did not validate an ST were excluded.
Results
1052 publications were initially identified across all searched databases. Title review identified 204 studies eligible for full text screening. 10 studies were included for final review. Two studies assessed both face and content, 4 face and construct, and 4 face, content and construct validity. None of the studies presented comparable outcomes due to metrics variation and scores used for the validation strategies.
Conclusions
This study assessed validated laparoscopic simulation models, particularly in content and construct validity. Articles reported an increased use of simulation models in laparoscopic training with positive feedback from trainees, but few studies reported validation of training model. Validation strategies are not standardized, limiting comparability between them.
Nowadays, bearings installed in industrial electric motors are constituted as the primary mode of a failure affecting the global energy consumption. Since industries’ energy demand has a growing ...tendency, interest for efficient maintenance in electric motors is decisive. Vibration signals from bearings are employed commonly as a non-invasive approach to support fault diagnosis and severity evaluation of rotating machinery. However, vibration-based diagnosis poses a challenge concerning the signal properties, e.g., highly dynamic and non-stationary. Here, we introduce a knowledge-based tool to analyze multiple health conditions in bearings. Our approach includes a stochastic feature selection method, termed Stochastic Feature Selection (SFS), highlighting and interpreting relevant multi-domain attributes (time, frequency, and time–frequency) related to the bearing faults discriminability. In particular, a relief-F-based ranking and a Hidden Markov Model are trained under a windowing scheme to achieve our SFS. Obtained results in a public database demonstrate that our proposal is competitive compared to state-of-the-art algorithms concerning both the number of features selected and the classification accuracy.
Tobacco use is associated with diseases worldwide, including cancer. This is one of the major public health problems globally, causing more than 19 million new cases in 2020. Lip and oral cavity ...cancer (LOCC) is neoplastic growth in the tongue, gums, and lips. The objective of this ecological study was to quantify the strength of the association between incidence and mortality of LOCC, with tobacco use and with the Human Development Index (HDI). Incidence and mortality data on LOCC were obtained for 172 countries in 2020, from the Global Cancer Observatory (GLOBOCAN). The prevalence of tobacco smoking and chewing was obtained from reports conducted in 2019. The inequality in human development was estimated using the HDI from the United Nations Development Program, Human Development Report (2019). Statistically significant correlations were observed between the incidence of LOCC and tobacco smoking and chewing prevalence, except for negative correlations between the prevalence of tobacco smoking LOCC mortality in women, just as in the case of the HDI. No statistically significant differences were found between the prevalence of tobacco chewing only and the incidence of LOCC overall and by sex. A higher LOCC incidence overall and by sex was associated with higher HDI. In conclusion, the present study found positive correlations for various HDI socioeconomic indicators and tobacco use with the incidence and mortality of LOCC, but also a few inverse correlations.
Prefabricated metal crowns (PMCs) have been widely used in pediatric dentistry due to their great success in various clinical situations. However, it is important to know the local effects, such as ...changes in pH in the oral environment.
To evaluate the pH variations before and after placement of PMCs.
A quasi-experimental study (before and after) was performed with 32 pediatric patients who needed rehabilitation with PMCs at a pediatric dentistry clinic in a public university. Measurements were made using a pH potentiometer before PMC placement, one week after, and one month after placement. ANOVA and Pearson correlation were performed in SPSS.
The average age of the participants was 5.9 ± 1.6 years, and 53.1% were female. The average pH before, one week after, and one month after crown placement was 7.46 ± 0.37, 7.00 ± 0.32, and 7.1 ± 0.19, respectively. Significant differences (p< 0.05) were observed between the three pH measurements. We found differences when comparing the basal pH values to those at one week (p= 0.001) and one month (p= 0.002).
Although there were statistically significant differences in the pH change values before and after the placement of crowns, these differences may not have a clinical impact.
The field of memory studies tends to focus attention on the '3Ms' - museums, monuments, memorials - as sites where memories are constructed, communicated, and contested. Where education is identified ...as a site for memory, the focus is often narrowly on what is or is not communicated within curricula or textbooks, assuming that schools simply pass on messages agreed or struggled over elsewhere. This article explores the possibilities opened when educative processes are not taken as stable and authoritative sites for transmitting historical narratives, but instead as spaces of contestation, negotiation and cultural production. With a focus on 'difficult histories' of recent conflict and historical injustice, we develop a research agenda for education as a site of memory and show how this can illuminate struggles over dominant historical narratives at various scales, highlighting agencies that educational actors bring to making sense of the past.
Artisanal and small-scale gold mining (ASGM) has been performed in the southern Ecuadorian Amazon since the colonial period. However, its effects on fluvial systems have been poorly investigated. ...Thus, in order to calculate the normalized enrichment factors (NEF) of several heavy metals in fluvial sediments of the Zamora River basin (Ecuadorian Amazon), we analyzed bottom sediments along ASGM-affected and unaffected river sections. The results indicated that sediments of the Congüime River have NEF between 2.2 and 2.3 for Cu (moderate contamination) and higher than 3 for Mn, Zn, Pb, and Hg (severe contamination). Similarly, a severe contamination is also observed in the lower Nangaritza River, due to sediments of this sector have NEF > 3 for Zn, Pb, and Hg. Bottom sediments from the Nambija and Zamora rivers showed a severe contamination with Hg (NEF > 3), suggesting the existence of ASGM activities in the upper Zamora River basin.
Multiple cerebral arteriovenous malformations (AVMs) are a rare occurrence usually associated with defined genetic disorders or a family history of cerebrovascular disease. The remaining cases cannot ...be associated to a genetic pathogenesis and are considered idiopathic. We report an extremely unusual case nor genetic neither idiopathic, but linked to an anatomical intracranial venous variation. The patient presented two independent frontal AVMs associated with rostral hypoplasia of the superior sagittal sinus. This anatomical variation may have induced frontal venous hypertension (VHT) triggering the development of the two AVMs. Throughout this intriguing case, we discuss the role of VHT in AVM development.
•High sucrose diet impairs motor skill learning at 20 and 40 weeks of treatment.•High sucrose diet groups do not show anxiety-like behaviors.•Insulin resistance correlated negatively with motor skill ...learning.•Insulin resistance increase C reactive protein.
Motor learning skills are reliable indicators of behavioral acquisition and cognitive disorders. The ease with which learning skills are measured disparities the complexity of the interpretation concerning neural plasticity. Conversely, a wealth of information regarding metabolic derangements has long been reported with direct connection to high sucrose diets. However, the impact of excessive sucrose consumption on undergoing cognitive processes has been only scarcely addressed up to now. Therefore, the goal of this work was to describe the associative relationship between high sucrose consumption and changes in motor learning skills acquisition. Motor learning impairments conditioned by central alterations are hypothesized. Rotarod, elevated plus-maze and open field trials, along with metabolic and pro-inflammatory biomarkers tests in Wistar rats under a high sucrose treatment, were performed. Motor learning impairment in high sucrose diet-treated rats was found while spontaneous locomotor activity remained unchanged. Even though, no anxiety-like behavior under high sucrose diet-treatment was observed. Consistently, the worst outcome in the glucose tolerance test was developed, the worst motor learning performance was observed. Furthermore, insulin resistance correlated positively with a pro-inflammatory state and a decreased latency to fall in the rotarod test. Indeed, C-reactive protein and tumor necrosis factor-α serum levels, along with the homeostasis model assessment of insulin resistance (HOMA-IR), significantly increased in motor learning impairment. Together, these results support behavioral, metabolic and pro-inflammatory changes associated with deleterious changes in central nervous system likely involving crucial motor learning structures. Underlying pro-inflammatory-triggered processes may explain cognitive disorders in advanced states of metabolic derangements.
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Several investigations of the X-ray variability of active galactic nuclei (AGN) using the normalised excess variance (\({\sigma^2_{\rm NXS}}\)) parameter have shown that variability has a strong ...anti-correlation with black hole mass (\(M_{\rm BH}\)) and X-ray luminosity (\(L_{\rm X}\)). In this study we confirm these previous correlations and find no evidence of a redshift evolution. Using observations from XMM-Newton, we determine the \({\sigma^2_{\rm NXS}}\) and \(L_{\rm X}\) for a sample of 1091 AGN drawn from the XMM-Newton Cluster Survey (XCS) - making this the largest study of X-ray spectral properties of AGNs. We created light-curves in three time-scales; 10 ks, 20 ks and 40 ks and used these to derive scaling relations between \({\sigma^2_{\rm NXS}}\), \(L_{\rm X}\) (2.0-10 keV range) and literature estimates of \(M_{\rm BH}\) from reverberation mapping. We confirm the anti-correlation between \(M_{\rm BH}\) and \({\sigma^2_{\rm NXS}}\) and find a positive correlation between \(M_{\rm BH}\) and \(L_{\rm X}\). The use of \({\sigma^2_{\rm NXS}}\) is practical only for pointed observations where the observation time is tens of kiloseconds. For much shorter observations one cannot accurately quantify variability to estimate \(M_{\rm BH}\). Here we describe a method to derive \(L_{\rm X}\) from short duration observations and used these results as an estimate for \(M_{\rm BH}\). We find that it is possible to estimate \(L_{\rm X}\) from observations of just a few hundred seconds and that when correlated with \(M_{\rm BH}\), the relation is statistically similar to the relation of \(M_{\rm BH}\)-\(L_{\rm X}\) derived from a spectroscopic analysis of full XMM observations. This method may be particularly useful to the eROSITA mission, an all-sky survey, which will detect \(>\)10\(^{6}\) AGN.
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