GPS vertical axis performance enhancement for helicopter precision landing approach

Several areas were investigated for improving vertical accuracy for a rotorcraft using the differential Global Positioning System (GPS) during a landing approach. Continuous deltaranging was studied and the potential improvement achieved by estimating acceleration was studied by comparing the performance on a constant acceleration turn and a rough landing profile of several filters: a position-velocity (PV) filter, a position-velocity-constant acceleration (PVAC) filter, and a position-velocity-turning acceleration (PVAT) filter. In overall statistics, the PVAC filter was found to be most efficient with the more complex PVAT performing equally well. Vertical performance was not significantly different among the filters. Satellite selection algorithms based on vertical errors only (vertical dilution of precision or VDOP) and even-weighted cross-track and vertical errors (XVDOP) were tested. The inclusion of an altimeter was studied by modifying the PVAC filter to include a baro bias estimate. Improved vertical accuracy during degraded DOP conditions resulted. Flight test results for raw differential results excluding filter effects indicated that the differential performance significantly improved overall navigation accuracy. A landing glidepath steering algorithm was devised which exploits the flexibility of GPS in determining precise relative position. A method for propagating the steering command over the GPS update interval was implemented

Simulation and analysis of differential global positioning system for civil helicopter operations

A Differential Global Positioning System (DGPS) computer simulation was developed, to provide a versatile tool for assessing DGPS referenced civil helicopter navigation. The civil helicopter community will probably be an early user of the GPS capability because of the unique mission requirements which include offshore exploration and low altitude transport into remote areas not currently served by ground based Navaids. The Monte Carlo simulation provided a sufficiently high fidelity dynamic motion and propagation environment to enable accurate comparisons of alternative differential GPS implementations and navigation filter tradeoffs. The analyst has provided the capability to adjust most aspects of the system, the helicopter flight profile, the receiver Kalman filter, and the signal propagation environment to assess differential GPS performance and parameter sensitivities. Preliminary analysis was conducted to evaluate alternative implementations of the differential navigation algorithm in both the position and measurement domain. Results are presented to show that significant performance gains are achieved when compared with conventional GPS but that differences due to DGPS implementation techniques were small. System performance was relatively insensitive to the update rates of the error correction information

Complications and mortality of Cushing’s disease: report on data collected over a 20-year period at a referral centre

Context: Cushing’s disease (CD) is rare condition burdened by several systemic complications correlated to higher mortality rates. The primary goal of clinicians is to achieve remission, but it is unclear if treatment can also increase life expectancy. Aim: To assess the prevalence of cortisol-related complications and mortality in a large cohort of CD patients attending a single referral centre. Materials and methods: The clinical charts of CD patients attending a referral hospital between 2001 and 2021 were reviewed. Results: 126 CD patients (median age at diagnosis 39 years) were included. At the last examination, 78/126 (61.9%) of the patients were in remission regardless of previous treatment strategies. Patients in remission showed a significant improvement in all the cardiovascular (CV) comorbidities (p < 0.05). The CV events were more frequent in older patients (p = 0.003), smokers and persistent CD groups (p < 0.05). Most of the thromboembolic (TE) and infective events occurred during active stages of the disease. The CV events were the most frequent cause of death. The standardized mortality ratio (SMR) resulted increased in persistent cases at the last follow-up (SMR 4.99, 95%CI [2.15; 9.83], p < 0.001) whilst it was not higher in those in remission (SMR 1.66, 95%CI [0.34; 4.85], p = 0.543) regardless of the timing or number of treatments carried out. A younger age at diagnosis (p = 0.005), a microadenoma (p = 0.002), and remission status at the last follow-up (p = 0.027) all increased survival. Furthermore, an elevated number of comorbidities, in particular arterial hypertension, increased mortality rates. Conclusions: Patients with active CD presented a poor survival outcome. Remission restored the patients’ life expectancy regardless of the timing or the types of treatments used to achieve it. Persistent CD-related comorbidities remained major risk factors

Cervical disc herniation and cervical spondylosis surgically treated by Cloward procedure: a 10-year-minimum follow-up study

BACKGROUND: Cervical degenerative pathology produces pain and disability, and if conservative treatment fails, surgery is indicated. The aim of this study was to determined whether anterior decompression and interbody fusion according to Cloward is effective for treating segmental cervical degenerative pathology and whether the results are durable after a 10-year-minimum follow-up. MATERIALS AND METHODS: Fifty-one patients affected by single-level cervical degenerative pathology between C4 and C7 were surgically treated by the Cloward procedure. Clinical evaluation was rated using the Neck Disability Index (NDI) and the visual analog scale (VAS). At last follow-up, the outcomes were rated according to Odom's criteria. On radiographs, the sagittal segmental alignment (SSA) of the affected level and the sagittal alignment of the cervical spine (SACS) were measured. RESULTS: Average NDI was 34 preoperatively and 11 at last follow-up. Average VAS was 7 preoperatively and 1 at last follow-up. According to Odom's criteria, the outcome was considered excellent in 18 cases, good in 22, and fair in 11. Average SSA was 0.5 +/- 2.1 preoperatively, 1.8 +/- 3.8 at 6 months, and 1.8 +/- 5.7 at last follow-up. Average SACS was 16.5 +/- 4.0 preoperatively, 20.9 +/- 5.8 at 6 months, and 19.9 +/- 6.4 at last follow-up. Degenerative changes at the adjacent levels were observed in 18 patients (35.3%). CONCLUSIONS: The Cloward procedure proved to be a suitable and effective technique for treating segmental cervical degenerative pathology, allowing good clinical and radiographic outcomes even at a long-term follow-up

Decoding Information From Neural Signals Recorded Using Intraneural Electrodes: Toward the Development of a Neurocontrolled Hand Prosthesis

The possibility of controlling dexterous hand prostheses by using a direct connection with the nervous system is particularly interesting for the significant improvement of the quality of life of patients, which can derive from this achievement. Among the various approaches, peripheral nerve based intrafascicular electrodes are excellent neural interface candidates, representing an excellent compromise between high selectivity and relatively low invasiveness. Moreover, this approach has undergone preliminary testing in human volunteers and has shown promise. In this paper, we investigate whether the use of intrafascicular electrodes can be used to decode multiple sensory and motor information channels with the aim to develop a finite state algorithm that may be employed to control neuroprostheses and neurocontrolled hand prostheses. The results achieved both in animal and human experiments show that the combination of multiple sites recordings and advanced signal processing techniques (such as wavelet denoising and spike sorting algorithms) can be used to identify both sensory stimuli (in animal models) and motor commands (in a human volunteer). These findings have interesting implications, which should be investigated in future experiments. © 2006 IEEE

THE BASE SYSTEM: A SCHOOL-WIDE POSITIVE BEHAVIOUR SUPPORT TOOL TO FACILITATE EVIDENCE-BASED DIGITAL INTERVENTION PRACTICES

The Positive Behaviour Intervention and Support system is a framework aimed to introduce a change at school-wide level. It promotes a disciplinary system change process, from a reactive punishment- based strategies of specific student misbehaviours to a proactive system, where different behavioural principles such as the modelling and reinforcement of positive prosocial students’ behaviours are applied to improve school values and to create a positive climate. This paper presents the Behavioural Assessment to improve School Environment (BASE) system and the BASE repository. The BASE system supports evidence-based digital intervention practices for stimulating the academic, social, emotional, and behavioural competencies of all students. The BASE repository is a collection of good practices, tools, and instructional contents. Both of the tools are able to support and facilitate, through the use of mobile devices and a web-based responsive system, different prevention and instructional practices at the three-tiers PBS model. At the first level of prevention (Tier 1) the system allows to the school PBS team to define the Expectation Matrix, a set of positive behaviours grouped according to predefined school values and locations. Moreover, the PBS team members are able to define the list of problem behaviours, classifying them in minor and major. The matrix and the list of minor and major problem behaviours are at the base of the development of a screening tool for identifying behavioural risk problems, the Positive Office Referral and the Office Disciplinary Referral tools. At the target prevention level (Tier 2) the BASE application provides the Check-in/Check-out (CICO) tool, as PBIS recommends. It is addressed to a targeted group of students, resulted unresponsive to the Tier I, and implements the practice of ‘Positive reinforcement contingent on meeting behavioural goals’ throughout a reward system. At the intensive prevention level (Tier 3) the system allows users to perform Functional Behaviour Assessment for students considered unresponsive to Tier I and II and to create customized measurement tools for designing single case studies. The measure can be assigned to the observers able to collect data and organize them in phases. A TAU analysis algorithm is applied to the gathered data for showing the effectiveness of intervention. In the BASE application, each student can access to the system with personal credentials and to visualize his significant progresses into a smart dashboard. The BASE repository represents a hub for digital resources collection concerning both theoretical and methodological aspects of the PBIS approach. The Internet users interested to know the European experience of the involved partner schools, and to enlarge their knowledge about the principles to implement the PBIS in their own school, can find a first set of multimedia contents, webinars, collection of good practices gathered during the lifespan of the European Erasmus+ BASE project. The repository facilitates the finding of high-quality contents and represents a learning corner and an important knowledge repository for teachers and health professionals to understand and apply this approach

Hip viscosupplementation under ultra-sound guidance riduces NSAID consumption in symptomatic hip osteoarthritis patients in a long follow-up. Data from Italian registry.

Introduction: Non-steroidal anti-inflammatory drugs (NSAIDs) consumption is strictly related to a high gastrointestinal and cardiovascular mortality and morbidity rate. Osteoarthritis Research Society International (OARSI) recommendations in patients with symptomatic hip or knee OA stated that NSAIDs should be used at the lowest effective dose but their long-term use should be avoided if possible. OARSI guidelines for the treatment of the hip OA include the use of viscosupplementation, which aims to restore physiological and Theological features of the synovial fluid. Objective: Aim of this multicentric, open and retrospective study is to investigate if NSAID consumption may be reduced by the use of ultrasound-guided intra-articular injection of several hyaluronic acid (HA) products in hip joint administered in patients affected by symptomatic hip OA. Materials and Methods: Patients affected by mono or bilateral symptomatic hip OA according to American Rheumatology Association (ARA) criteria, radiological OA graded II-IV (Kellgren and Lawrence) entered the study and were administered with ultrasound-guided intra-articular injection of hyaluronic acid products. As a primary endpoint, consumption of NSAIDs was evaluated by recording the number of days a month (range 0-30) the patient had used NSAID during the previous month, reported at each visit during the 24 months follow-up period. Secondary endpoints included further analysis for subgroups of patients categorized for Lequesne index score, Kellgren-Lawrence score, pain visual analogue scale (VAS) score, ultrasound pattern, age, hyaluronic acid used. Results: 2343 patients entered the study. Regarding primary endpoint, the consumption of NSAIDs was reduced of 48.2% at the third month when compared with baseline values. This sparing effect increased at 12th and 24th month with a reduction respectively of 50% and 61% in comparison to baseline values. These differences were statistically significant. Conclusions: These data point out that intraarticular hyaluronan preparations provide OA pain relief and reduce NSAIDs consumption in a large cohort of patients for a long period of follow-up. Multiple courses of viscosupplementation (vs) are required to maintain low dose of NSAID consumption over time. NSAIDs consumption is strictly related to an high gastrointestinal and cardiovascular mortality and morbidity rate, instead HA intra-articular treatment is well tolerated and is associated with a low incidence of adverse effects. For these reasons further studies evaluating cost-effectiveness and cost-utility of VS in the management of hip OA are required

Predictors of Patient-Reported Dysphagia Following IMRT Plus Chemotherapy in Oropharyngeal Cancer

The aim of this cross-sectional study is to evaluate the factors associated with patient-reported dysphagia in patients affected by locally advanced oropharyngeal cancer (OPC) treated with definitive intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy (CHT), with or without induction CHT. We evaluated 148 OPC patients treated with IMRT and concurrent CHT, without evidence of disease and who had completed their treatment since at least 6 months. At their planned follow-up visit, patients underwent clinical evaluation and completed the M.D. Anderson dysphagia inventory (MDADI) questionnaire. The association between questionnaire composite score (MDADI-CS) and different patients\u2019 and tumor\u2019s characteristics and treatments (covariates) was investigated by univariable and multivariable analyses, the latter including only covariates significant at univariable analysis. With a median time from treatment end of 30 months [range 6\u201374 months, interquartile range (IQR) 16\u201350 months], the median (IQR) MDADI-CS was 72 (63\u201384). The majority of patients (82.4%) had a MDADI-CS 65 60. At multivariable analysis, female gender, human papilloma virus (HPV)-negative status, and moderate and severe clinician-rated xerostomia were significantly associated with lower MDADI-CS. Patient-perceived dysphagia was satisfactory or acceptable in the majority of patients. HPV status and xerostomia were confirmed as important predictive factors for swallowing dysfunction after radiochemotherapy. Data regarding female gender are new and deserve further investigation