The regularized visible fold revisited

The planar visible fold is a simple singularity in piecewise smooth systems. In this paper, we consider singularly perturbed systems that limit to this piecewise smooth bifurcation as the singular perturbation parameter $\epsilon\rightarrow 0$. Alternatively, these singularly perturbed systems can be thought of as regularizations of their piecewise counterparts. The main contribution of the paper is to demonstrate the use of consecutive blowup transformations in this setting, allowing us to obtain detailed information about a transition map near the fold under very general assumptions. We apply this information to prove, for the first time, the existence of a locally unique saddle-node bifurcation in the case where a limit cycle, in the singular limit $\epsilon\rightarrow 0$, grazes the discontinuity set. We apply this result to a mass-spring system on a moving belt described by a Stribeck-type friction law

Duodenal carcinoma at the ligament of Treitz. A molecular and clinical perspective

Background There is very small occurrence of adenocarcinoma in the small bowel. We present a case of primary duodenal adenocarcinoma and discuss the findings of the case diagnostic modalities, current knowledge on the molecular biology behind small bowel neoplasms and treatment options. Case The patient had a history of iron deficiency anemia and occult bleeding with extensive workup consisting of upper endoscopy, colonoscopy, capsule endoscopy, upper gastrointestinal series with small bowel follow through and push enteroscopy. Due to persistent abdominal pain and iron deficiency anemia the patient underwent push enteroscopy which revealed adenocarcinoma of the duodenum. The patient underwent en-bloc duodenectomy which revealed T3N1M0 adenocarcinoma of the 4th portion of the duodenum. Conclusions Primary duodenal carcinoma, although rare should be considered in the differential diagnosis of occult gastrointestinal bleeding when evaluation of the lower and upper GI tract is unremarkable. We discuss the current evaluation and management of this small bowel neoplasm

Performance of clear vacuum-formed thermoplastic retainers depending on retention protocol: a systematic review

We aimed at comparing the performance of vacuum-formed thermoplastic retainers (VFR) worn either full-time or part-time, in maintaining orthodontic treatment results in terms of tooth alignment, arch form and occlusion. We reviewed randomized and prospective controlled clinical trials comparing VFR wearing protocols and searched databases, without restrictions, for published and unpublished literature. The risk of bias was assessed using the Cochrane Risk of Bias tool and the overall level of certainty in the evidence following ADA methodology. 184 studies were initially identified and reduced to the 3 randomized controlled trials included in the systematic review by means of specific criteria. One study followed patients 1 year into retention, and the other two for 6 months. Little's Irregularity Index, intermolar and intercanine width, arch length, overjet and PAR score did not differ significantly between the patients wearing their retainers part time or full time. We observed a slight increase in the overbite in the part-time group in only one trial. With a moderate level of certainty, we found that during the observation period, full-time VFR wear is not superior to part-time, bearing in mind the potential implications for health burden, retainer longevity and cost-effectiveness, as well as patient satisfaction and compliance

Evidence based electronic system to ensure quality of care in trauma patients

Electronic patient records are important for quality health services. Aim of this study is to support the trauma patient care with the development of an electronic system. A survey was conducted in the Emergency Department (ED) of a University hospital to study the effectiveness of an electronic monitoring system in a group of trauma patients, as well as the acceptance of this electronic system by the health professionals of the ED. A questionnaire collected information about the perceptions of 50 health professionals working in the ED on various aspects of patient care. The 86% (?=43) replied that there is lack of staff working in their department, 44% (N=22) is satisfied with the co-operation with other departments and 48% (N=24) believe that they spend precious time in administrative work during the care. For the purpose of a more efficient patient monitoring there was developed an electronic trauma patient monitoring system which was evaluated by the above mentioned professionals. The severity, length of care and the health outcomes of 200 trauma patients, were investigated. Half of the patients (N=100) have been monitored by the electronic system and the other 100 were monitored without the use of the system. The time between the admission and completion of the planned care was significantly lower in the electronic monitoring patient group (100?92 minutes) compared to the control group (149?29 minutes). © 2012 European Federation for Medical Informatics and IOS Press. All rights reserved

Patient-reported experiences and preferences with intraoral scanners: a systematic review

BACKGROUND: Intraoral scanners have become an increasingly popular alternative to conventional impression methods. Although their accuracy and validity have been examined thoroughly, patient-reported information including experiences, preferences, and satisfaction has not yet been investigated in a systematic way. OBJECTIVE: The objective of this systematic review is to investigate the available data and appraise the evidence on patient-reported experiences and preferences following impression taking with intraoral scanners. SEARCH METHODS: Unrestricted search of seven databases (Pubmed, CENTRAL, Cochrane reviews, Scopus, Web of Science, Clinical Trials, and ProQuest) and grey literature were conducted until October 2020. Detailed search strategies were developed for each database. SELECTION CRITERIA: Studies involving individuals of any gender or age, subjected to full arch impression taking with conventional and intraoral scanning methods were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Following the retrieval and selection of the studies, data extraction was performed. Risk of bias assessment was performed using the RoB 2 and ROBINS-I tools. RESULTS: From the initially identified records, nine studies [eight crossover (two of them randomized) and one parallel group] were eventually included in the present systematic review. Randomized studies were shown, overall, to have some concerns regarding bias, whereas the non-randomized studies were found to be at serious risk, mainly because of bias due to confounding. All studies demonstrated some benefit in favour of intraoral scanning compared with conventional techniques. More positive feelings were generally observed with the intraoral scanners regarding smell, taste, sound, vibration, nausea, and queasiness. Overall, comfort assessment mostly favoured digital methods. No differences were found concerning the level of anxiety between the two methods. Among the included studies, time perception was a parameter leading to contradictory results. LIMITATIONS: These emerge due to the nature and characteristics of the information retrieved from the included studies. The validation of the instruments to capture patient-reported outcomes needs to be further elaborated. CONCLUSIONS: Intraoral scanners seem to be a promising new asset in the orthodontic office from the perspective of individuals' experiences and preferences. Nevertheless, to investigate patient-reported outcomes correctly, further high-quality studies are required in the future. REGISTRATION: Open Science Framework (https://osf.io/ayug2/). © The Author(s) 2021. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: [email protected]

Obesity and diabetes: never say never again!

There is no doubt that the obesity ‘epidemic’ is with us. The complex relationship between the environment and the development of obesity is highly studied, but the interaction between the environment, genetic predisposition and life style is not easy to understand. Energy balance, biological function and body composition are three closely correlated entities in the study of obesity, and it is often not easy to tease out cause and effect. In both adults and children, the high prevalence of obesity is a concern, given the associated health risks that included elevated blood pressure, hyperinsulinemia, glucose intolerance and type 2 diabetes, dislipidaemia and other risks for cardiac disease

In vivo effect of carbon dioxide laser-skin resurfacing and mechanical abrasion on the skin's microbial flora in an animal model

BACKGROUND Although beam-scanning carbon dioxide (CO2) lasers have provided a highly efficient tool for esthetic skin rejuvenation there has been no comprehensive animal studies looking into microbial skin changes following CO2 laser skin resurfacing. OBJECTIVE To evaluate the in vivo effects of CO2 laser skin resurfacing in an experimental rat model in comparison with mechanical abrasion on the skin microbial flora. METHODS Four separate cutaneous sections of the right dorsal surface of 10 Wistar rats were treated with a CO2 laser, operating at 18W and delivering a radiant energy of 5.76J/cm(2), while mechanical abrasions of the skin were created on four sections of the left dorsal surface using a scalpel. Samples for culture and biopsies were obtained from the skin surfaces of the rats on day 1 of application of the CO2 laser or mechanical abrasion, as well as 10, 30, and 90 days after the procedure. The presence of four microorganisms (staphylococci, streptococci, diphtheroids, and yeasts) was evaluated as a microbe index for the skin flora, and colony counts were obtained using standard microbiological methods. RESULTS Skin biopsy specimens, following CO2 laser treatment, initially showed epidermal and papillary dermal necrosis and later a re-epithelization of the epidermis as well as the generation of new collagen on the upper papillary dermis. The reduction in microbial counts on day 1 of the CO2 laser-inflicted wound was statistically significant for staphylococci and diphtheroids compared with the baseline counts (p=.004 and p <.001, respectively), and for staphylococci, diphtheroids, and yeasts compared with the scalpel-inflicted wound on the same day (p=0.029, p <.001, and p=.030, respectively). CONCLUSIONS Skin resurfacing using CO2 lasers considerably reduces microbial counts of most microorganisms in comparison with either normal skin flora or a scalpel-inflicted wound. This might contribute to the positive clinical outcome of laser skin resurfacing

Esophageal Carcinoma: Current Controversial Topics

Worldwide, esophageal carcinoma is a common gastrointestinal cancer with a high mortality. The incidence of adenocarcinoma of the esophagus is increasing in the western world, but squamous cell carcinoma remains dominant in the underdeveloped parts of the world. Both types of esophageal carcinoma remain equally virulent. Currently, there are no optimal preventative screening programs available and most patients present with advanced or metastatic disease. Although many options are available for improving diagnostic accuracy, a single method has not displayed significant advantages over the others. In addition, selecting a superior treatment regimen has not surfaced. Preferred resection techniques exist, but one method has not illustrated improvements in survival over the others. A lack of improved survival rates with single modality therapies has led to a multi modality approach. However, developments in neoadjuvant and adjuvant therapies have led to mixed conclusions. Collectively, past studies have not shown an optimal neoadjuvant or adjuvant regimen in terms of survival benefit. This review highlights existing staging modalities and treatment regimens for esophageal carcinoma, in an effort to illustrate the controversial nature surrounding its management