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The seventh edition of the AASHTO LRFD Bridge Design Specifications (2016 interim) includes revised provisions for the design of deep beams using the strut-and-tie method. The validity and accuracy of these provisions as applied to simply supported deep beams loaded in a manner that generates an inflection point between the supports was investigated in this research. As part of a course-related laboratory investigation, graduate students at the University of Texas at Austin used these provisions to design two reduced-scale deep beams. The specimens were subsequently constructed and tested. The experimental behaviors of the specimens including governing failure modes, load-displacement curves, and their ultimate capacities were investigated and compared with estimates developed from the strut-and-tie method. The results obtained validated the suitability of the revised provisions for the design of deep beams with inflection points located between supports. Additionally, the students developed pre-test estimates for the behaviors and strengths of the two deep beam specimens using the finite element software program VecTor2. While there was some variation among the computed responses, the blind predictions accurately captured governing failure modes and provided reasonable capacity estimates. Keywords: deep beam; finite element analysis of reinforced concrete; strut-and-tie.

Objective To assess the long-term efficacy and safety of bilateral subthalamic nucleus (STN) stimulation in patients with advanced Parkinson’s disease (PD). Methods 42 consecutive patients with idiopathic PD treated with bilateral STN stimulation were enrolled. Parkinsonian status, medication intake and neuropsychological evaluation were assessed preoperatively and at 1 and 5 years postoperatively in on and off medication/on and off stimulation conditions. Results 23 patients could be followed-up 5 years after surgery. In the remaining cases, 5 died, 1 could not be assessed because of device removal for infection, 1 decided not to be stimulated, and 11 were lost of follow-up (one because of a liver carcinoma and the others because they refused the formal four conditions of assessment). STN stimulation reduced the UPDRS motor score by 55 % compared to baseline in the offmedication conditions. Tremor, rigidity, bradykinesia, postural stability, and gait improved by 74 %, 66 %, 59 %, 17 % and 37 %, respectively. UPDRS part II scores were reduced by 38 %. The dopaminergic treatment daily dose was reduced by 54.4 % after surgery. Axial dopa-unresponsive signs worsened in some patients. Among the 42 initial patients we observed the following: 2 brain hemorrhages, 3 infections of the device, 2 phlebitis and 1 pulmonary embolism. In addition, 2 patients needed a repositioning of the electrode. Among the 23 patients followed at 5 years, long lasting side effects consisted in dysarthria (56 %), depression (39 %), eyelid opening apraxia (30.4 %) and apathy (4.3 %). Conclusions Our data confirm that bilateral STN stimulation is beneficial in the long-term for PD patients but does not prevent disease progression and the occurence of axial levodopa unresponsive signs in some patients.

Dalbavancin is a lipoglycopeptide approved for the treatment of acute bacterial skin and skin structure infections (ABSSSI). The aim of the study was to evaluate the efficacy and safety in all patients who received at least one administration of dalbavancin. Methods: We carried out a retrospective study of the use of dalbavancin in 55 patients at the Azienda Ospedaliera Ospedali Riuniti Umberto I (Ancona, Italy) from February 2017 to May 2020 and compared “on label” and “off label” use of dalbavancin in ABSSSI and non-ABSSSI. Results: A total of 55 patients were included in the study. The median age was 61 years; 51% had ABSSSI; 24% had prosthetic joint infections, and 14% had osteomyelitis. A total of 53% received a single 1500 mg infusion of dalbavancin, and 18% received a second dose 14 days later; 24% of patients received further doses at 14-day intervals. In 91% of cases, patients achieved clinical objectives with dalbavancin: 96% of patients with ABSSSI and 69% of those with prosthetic joint infections. Conclusions: Dalbavancin was shown to have an excellent tolerability profile and to be a highly successful therapeutic approach even in those cases treated “off-label”.

Background: Ceftazidime/avibactam is a new cephalosporin/beta-lactamase inhibitor combination approved in 2015 by the FDA for the treatment of complicated intra-abdominal and urinary tract infection, hospital-acquired pneumoniae and Gram-negative infections with limited treatment options. Methods: In this retrospective study, we evaluate the efficacy of ceftazidime/avibactam treatment in 81 patients with Gram-negative infection treated in our center from January 2018 to December 2019. The outcome evaluated was 30-days survival or relapse of infection after the first positive blood culture. Results: the majority of patients were 56 male (69%), with median age of 67. Charlson’s Comorbidity Index was >3 in 58 patients. In total, 46% of the patients were admitted into the medical unit, 41% in the ICU, and 14% in the surgical ward. Of the patients, 78% had nosocomial infections, and 22% had healthcare-related infections. The clinical failure rate was 35%: 13 patients died within 30 days from the onset of infection. The outcome was influenced by the clinical condition of the patients: solid organ transplantation (p = 0.003) emerged as an independent predictor of mortality; non-survival patients most frequently had pneumonia (p = 0.009) or mechanical ventilation (p = 0.049). Conclusion: Ceftazidime–avibactam showed high efficacy in infections caused by MDR Gram-negative pathogens with limited therapeutic options.

Management of Parkinson’s disease (PD) using deep brain stimulation (DBS) requires complex care in specialized, multidisciplinary centers. A well-organized, efficient patient flow is crucial to ensure that eligible patients can quickly access DBS. Delays or inefficiencies in patient care may impact a center’s ability to meet demand, creating a capacity bottleneck. Analysis of the current practices within a center may help identify areas for improvement. After external audit of the DBS workflow of the Lyon Neurological Hospital and comparison with other European centers, manageable steps were suggested to restructure the care pathway. Propositions of the audit comprised, for example: (1) directly admitting referred patients to hospital, without a prior neurological outpatient visit and (2) including the preoperative anesthesia consultation in the hospital stay 1 month before surgery, not separately. This reorganization (between 2013 and 2016) was performed without increases in hospital medical resources or costs. The time from patients’ first referral to surgery was reduced (from 22 to 16 months; p  = 0.033), as was the number of pre- and postoperative patient visits (11–5; p  = 0.025) and the total cumulative length of in-hospital stay (20.5–17.5 nights; p  = 0.02). Ultimately, the total number of PD consultations increased (346–498 per year), as did the number of DBS implants per year (32–45 patients). In this single center experience, restructuring the DBS care pathway allowed a higher number of PD patients to benefit from DBS therapy, with a shorter waiting time and without decreasing the quality of care.

1 - To assess the anatomical localization of the active contacts of deep brain stimulation targeted to the subthalamic nucleus (STN) in Parkinson's disease patients. 2 - To analyze the stereotactic spatial distribution of the active contacts in relation to the dorsal and the ventral electrophysiologically-defined borders of the STN and the stereotactic theoretical target. Twenty-eight patients underwent bilateral high-frequency stimulation of the STN (HFS-STN). An indirect anatomical method based on ventriculography coupled to electrophysiological techniques were used to localize the STN. Clinical improvement was evaluated by Unified Parkinson's Disease Rating Scale motor score (UPDRS III). The normalized stereotactic coordinates of the active contact centres, dorsal and ventral electrophysiologically-defined borders of the STN were obtained from intraoperative X-rays images. These coordinates were represented in a three-dimensional stereotactic space and in the digitalized atlas of the human basal ganglia. HFS-STN resulted in significant improvement of motor function (62.8%) in off-medication state and levodopa-equivalent dose reduction of 68.7% (p < 0.05). Most of the active contacts (78.6%) were situated close to (+/- 1.6 mm) the dorsal border of the STN (STN-DB), while 16% were dorsal and 5.4% were ventral to it. Similar distribution was observed in the atlas. The euclidean distance between the STN-DB distribution center and the active contacts distribution center was 0.31 mm, while the distance between the active contacts distribution center and the stereotactic theoretical target was 2.15 mm. Most of the space defined by the active contacts distribution (53%) was inside that defined by the STN-DB distribution. In our series, most of the active electrodes were situated near the STN-DB. This suggests that HFS-STN could influence not only STN but also the dorsal adjacent structures (zona incerta and/or Fields of Forel).

Purpose Meningeal solitary fibrous tumour (SFT) and haemangiopericytoma (HPC) are uncommon tumours that have been merged into a single entity in the last 2021 WHO Classification of Tumors of the Central Nervous System. To describe the epidemiology of SFT/HPC operated in France and, to assess their incidence. Methods We processed the French Brain Tumour Database (FBTDB) to conduct a nationwide population-based study of all histopathologically confirmed SFT/HPC between 2006 and 2015. Results Our study included 399 SFT/HPC patients, operated in France between 2006 and 2015, in one of the 46 participating neurosurgical centres. The incidence reached 0.062, 95% CI[0.056–0.068] for 100,000 person-years. SFT accounted for 35.8% and, HPC for 64.2%. The ratio of SFT/HPC over meningioma operated during the same period was 0.013. SFT/HPC are about equally distributed in women and men (55.9% vs. 44.1%). For the whole population, mean age at surgery was 53.9 (SD ± 15.8) years. The incidence of SFT/HPC surgery increases with the age and, is maximal for the 50–55 years category. Benign SFT/HPC accounted for 65.16%, SFT/HPC of uncertain behaviour for 11.53% and malignant ones for 23.31%. The number of resection progresses as the histopathological behaviour became more aggressive. 6.7% of the patients with a benign SFT/HPC had a second surgery vs. 16.6% in case of uncertain behaviour and, 28.4% for malignant SFT/HPC patients. Conclusion Meningeal SFT and HPC are rare CNS mesenchymal tumours which both share common epidemiological characteristics, asserting their merging under a common entity. SFT/HPC incidence is less that one case for 1 billion per year and, for around 100 meningiomas-like tumours removed, one SFT/HPC may be diagnosed. SFT/HPC are equally distributed in women and men and, are mainly diagnosed around 50–55 years. The more aggressive the tumour, the higher the probability of recurrence.

Using the Cognitive Apprenticeship Model to Develop Educational Learning Modules: An Example from StaticsThe use of computational modeling is fundamental to science and engineering. We present acognitive model of apprenticeship that incorporates computational modeling as an alternatemeans for overcoming students’ conceptual difficulties. Apprenticeship is rooted in helpingnovices become experts through guided learning. The cognitive model of apprenticeship placesfocus on cognitive and metacognitive aspects in achieving expertise. Learning principles of thismodel include: types of knowledge required for expertise, ways to promote its development,sequencing of the learning activities, and the social characteristics of the learning environment.Using these principles, we developed individual learning modules centered on difficult conceptsin Engineering Statics namely, moment of a force, truss analysis, and second moment of area –to guide conceptual understanding. Students complete each approximate three-hour learningmodule outside of class after they have attended lecture(s) and completed a series of textbookproblems over the individual concept. A course grader assesses performance by way of a rubric;a copy of which is provided in advance to the student as a reference, at the end of the module.These contextual learning modules can supplement already established STEM curricula and areused to target difficult concepts.