Fixed-base simulation study of decoupled controls during approach and landing of a STOL transport airplane

A fixed-base visual simulation study has been conducted to evaluate the use of decoupled controls as a means for reducing pilot workload during approach and landing of an externally blown jet-flap short take-off and landing (STOL) transport. All six rigid-body degrees of freedom were employed with the aerodynamic characteristics based on wind-tunnel data. The primary piloting task was to use a flight director to capture and maintain a two-segment glide slope, with a closed-circuit television display of a STOL airport used during simulations of the flare and landing. The decoupled longitudinal controls used constant prefilter and feedback gains to provide steady-state decoupling of flight-path angle, pitch angle, and forward velocity. The pilots were enthusiastic about the decoupled longitudinal controls but believed the decoupled concept offered no significant advantage over conventional controls in the lateral mode

Importance of the Student Therapist/Athlete Relationship and Goal-Setting in Injury Rehabilitation

Previous research has highlighted the importance of relationships (e.g., athletic therapist/client) and psychological skill use to manage negative emotions (e.g., frustration, anger) in order to obtain optimal adherence and injury rehabilitation outcomes. However, the relationship between student athletic therapists and varsity athletes has not been examined. Thus, the objective was to examine the relationship between student therapists and varsity athletes and psychological skill use in injury rehabilitation in relation to adherence. Two senior student therapists and three varsity athletes who had completed injury rehabilitation were recruited to participate in semi-structured interviews. Transcripts were analysed using thematic analysis. Both groups of participants described the role of the student therapists as being primarily focused on injury prevention and management. Furthermore, the peer relationships that developed were valued. Goal-setting was used in injury rehabilitation to guide progress, improve adherence, and frame injuries as temporary setbacks. Participants were familiar with imagery from use in other context, however did not report using it in injury rehabilitation. Finally, participants acknowledged that adherence was not perfect, but acknowledged the peer relationships and collaborative goal-setting as helpful. These findings highlight the importance of the relationship between student therapists and athletes and suggest these relationships may support athlete adherence

Modulation of nitric oxide synthase I transcription by Tau and Alpha-Synuclein and its relevance to Alzheimer\u27s and Parkinson\u27s diseases

Alzheimer\u27s Disease (AD) and Parkinson\u27s Disease (PD) are both progressive neurodegenerative disorders that affect millions of Americans and for which there are no cures. AD can significantly impair the ability to think, remember, communicate, and carry out daily activities, while PD can affect motor functions such as balance, coordination, and the ability to speak. Intracellular protein aggregation is a hallmark of both diseases, with AD being characterized by the build up of neurofibrillary tangles composed of misfolded tau protein and PD being characterized by Lewy bodies composed of alpha-synuclein. Both normal tau and alpha-synuclein can localize to the nucleus; however, their nuclear roles have not been fully elucidated. These proteins bind and stabilize alternative DNA structures, which form most readily at purine-pyrimidine repeats. The 1f promoter of the Nitric Oxide Synthase I (NOSI) gene, which is misregulated in both AD and PD, contains one such repeat. This NOSI repeat is polymorphic and has the sequence (TG)mTA(TG)n where m and n can vary from individual to individual. Genotyping shows that shorter dinucleotide polymorphisms are associated with AD and PD. Promoters with shorter repeats also have decreased transcriptional expression compared to promoters with larger repeats. Because tau and alpha-synuclein can bind such repeats, we hypothesize that tau and alpha-synuclein may modulate NOSI transcription through the (TG)nTA(TG)m repeat. Reporter genes directed by the NOSI 1f promoter with and without the (TG)nTA(TG)m repeat region were transfected into human neuroblastoma cells (SK-N-MC) and human cervical cancer cells (HeLa) that express varying levels of tau and alpha-synuclein. Promoters with the TG repeat directed approximately two-fold changes in reporter gene expression, while promoters without the TG repeat caused no change in expression. These findings suggest that tau and alpha-synuclein modulate NOSI expression through interaction with a dinucleotide polymorphism associated with disease development

Physics-based characterization of soft marine sediments using vector sensors

In a 2007 experiment conducted in the northern North Sea, observations of a low-frequency seismo-acoustic wave field with a linear horizontal array of vector sensors located on the seafloor revealed a strong, narrow peak around 38 Hz in the power spectra and a presence of multi-mode horizontally and vertically polarized interface waves with phase speeds between 45 and 350 m/s. Dispersion curves of the interface waves exhibit piece-wise linear dependences between the logarithm of phase speed and logarithm of frequency with distinct slopes at large and small phase speeds, which suggests a seabed with a power-law shear speed dependence in two distinct sediment layers. The power spectrum peak is interpreted as a manifestation of a seismo-acoustic resonance. A simple geoacoustic model with a few free parameters is derived that quantitatively reproduces the key features of the observations. This article's approach to the inverse problem is guided by a theoretical analysis of interface wave dispersion and resonance reflection of compressional waves in soft marine sediments containing two or more layers of different composition. Combining data from various channels of the vector sensors is critical for separating waves of different polarizations and helps to identify various arrivals, check consistency of inversions, and evaluate sediment density

Barrier Lowering and Field Penetration at Metal-Dielectric Interfaces

We report here photoemission measurements on Si-SiO_2-Al structures in which the metal-SiO_2 barrier energy has been determined as a function of the electric field strength E in the dielectric. The expected barrier lowering is the sum of two terms: a) the Schottky term, proportional to E^(1/2) and b) a term due to the penetration of the electric field into the metal electrode, proportional to E. The experimental results are in good agreement with the model, where the Schottky effect involves the optical value of the dielectric constant of the oxide and the Thomas-Fermi screening distance in the metal is 1 Å. To our knowledge this represents the first unambiguous quantitative determination of either effect in a polar dielectric, although the Schottky effect alone has been observed in silicon

Clinical outcomes and risk factors for COVID-19 among migrant populations in high-income countries: a systematic review

Background: Migrants, including refugees, asylum seekers, labour migrants, and undocumented migrants, now constitute a considerable proportion of most high-income countries’ populations, including their skilled and unskilled workforces. Migrants may be at increased risk of COVID-19 due to their health and social circumstances, yet the extent to which they are being affected and their predisposing risk factors are not clearly understood. We did a systematic review to assess clinical outcomes of COVID-19 in migrant populations (cases, hospitalisations, deaths), indirect health and social impacts, and to determine key risk factors. / Methods: We did a systematic review following PRISMA guidelines, registered with PROSPERO (CRD42020222135). We searched databases including PubMed, Global Health, Scopus, CINAHL, and pre-print databases (medRxiv) via the WHO Global Research on COVID-19 database to Nov 18, 2020 for peer-reviewed and grey literature pertaining to migrants (defined as foreign born) and COVID-19 in 82 high-income countries. We used our international networks to source national datasets and grey literature. Data were extracted on our primary outcomes (cases, hospitalisations, deaths) and we evaluated secondary outcomes on indirect health and social impacts, and risk factors, using narrative synthesis. / Results: 3016 data sources were screened with 158 from 15 countries included in the analysis (35 data sources for primary outcomes: cases [21], hospitalisations [4]; deaths [15]; 123 for secondary outcomes). We found that migrants are at increased risk of infection and are disproportionately represented among COVID-19 cases. Available datasets suggest a similarly disproportionate representation of migrants in reported COVID-19 deaths, as well as increased all-cause mortality in migrants in some countries in 2020. Undocumented migrants, migrant health and care workers, and migrants housed in camps and labour compounds may have been especially affected. In general, migrants have higher levels of many risk factors and vulnerabilities relevant to COVID-19, including increased exposure to SARS-CoV-2 due to high-risk occupations and overcrowded accommodation, and barriers to health care including inadequate information, language barriers, and reduced entitlement to healthcare coverage related to their immigration status. / Conclusions: Migrants in high-income countries are at high risk of exposure to, and infection with, COVID-19. These data are of immediate relevance to national public health responses to the pandemic and should inform policymaking on strategies for reducing transmission of COVID-19 in this population. Robust data on testing uptake and clinical outcomes in migrants, and barriers and facilitators to COVID-19 vaccination, are urgently needed, alongside strengthening engagement with diverse migrant groups. / Competing Interest Statement: The authors have declared no competing interest. / Clinical Protocols: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD4202022213

Clinical Practice Guidelines for Recall and Maintenance of Patients with Tooth-Borne and Implant-Borne Dental Restorations

Purpose To provide guidelines for patient recall regimen, professional maintenance regimen, and at-home maintenance regimen for patients with tooth-borne and implant-borne removable and fixed restorations. Materials and Methods The American College of Prosthodontists (ACP) convened a scientific panel of experts appointed by the ACP, American Dental Association (ADA), Academy of General Dentistry (AGD), and American Dental Hygienists Association (ADHA) who critically evaluated and debated recently published findings from two systematic reviews on this topic. The major outcomes and consequences considered during formulation of the clinical practice guidelines (CPGs) were risk for failure of tooth- and implant-borne restorations. The panel conducted a round table discussion of the proposed guidelines, which were debated in detail. Feedback was used to supplement and refine the proposed guidelines, and consensus was attained. Results A set of CPGs was developed for tooth-borne restorations and implant-borne restorations. Each CPG comprised (1) patient recall, (2) professional maintenance, and (3) at-home maintenance. For tooth-borne restorations, the professional maintenance and at-home maintenance CPGs were subdivided for removable and fixed restorations. For implant-borne restorations, the professional maintenance CPGs were subdivided for removable and fixed restorations and further divided into biological maintenance and mechanical maintenance for each type of restoration. The at-home maintenance CPGs were subdivided for removable and fixed restorations. Conclusions The clinical practice guidelines presented in this document were initially developed using the two systematic reviews. Additional guidelines were developed using expert opinion and consensus, which included discussion of the best clinical practices, clinical feasibility, and risk-benefit ratio to the patient. To the authors’ knowledge, these are the first CPGs addressing patient recall regimen, professional maintenance regimen, and at-home maintenance regimen for patients with tooth-borne and implant-borne restorations. This document serves as a baseline with the expectation of future modifications when additional evidence becomes available

A Systematic Review of Recall Regimen and Maintenance Regimen of Patients with Dental Restorations. Part 2: Implant-Borne Restorations

Purpose To evaluate the current scientific evidence on patient recall and maintenance of implant-supported restorations, to standardize patient care regimens and improve maintenance of oral health. An additional purpose was to examine areas of deficiency in the current scientific literature and provide recommendations for future studies. Materials and Methods An electronic search for articles in the English language literature from the past 10 years was performed independently by multiple investigators using a systematic search process. After application of predetermined inclusion and exclusion criteria, the final list of articles was reviewed to meet the objectives of this review. Results The initial electronic search resulted in 2816 titles. The systematic application of inclusion and exclusion criteria resulted in 14 articles that satisfied the study objectives. An additional 6 articles were added through a supplemental search process for a total of 20 studies. Of these, 11 were randomized controlled clinical trials, and 9 were observational studies. The majority of the studies (15 out of 20) were conducted in the past 5 years and most studies were conducted in Europe (15), followed by Asia (2), South America (1), the United States (1), and the Middle East (1). Results from the qualitative data on a combined 1088 patients indicated that outcome improvements in recall and maintenance regimen were related to (1) patient/treatment characteristic (type of prosthesis, type of prosthetic components, and type of restorative materials); (2) specific oral topical agents or oral hygiene aids (electric toothbrush, interdental brush, chlorhexidine, triclosan, water flossers) and (3) professional intervention (oral hygiene maintenance, and maintenance of the prosthesis). Conclusions There is minimal evidence related to recall regimens in patients with implant-borne removable and fixed restorations; however, a considerable body of evidence indicates that patients with implant-borne removable and fixed restorations require lifelong professional recall regimens to provide biological and mechanical maintenance, customized for each patient. Current evidence also demonstrates that the use of specific oral topical agents and oral hygiene aids can improve professional and at-home maintenance of implant-borne restorations. There is evidence to demonstrate differences in mechanical and biological maintenance needs due to differences in prosthetic materials and designs. Deficiencies in existing evidence compel the forethought of creating clinical practice guidelines for recall and maintenance of patients with implant-borne dental restorations

Fixed base simulator study of an externally blown flap STOL transport airplane during approach and landing

A fixed-base simulator study was conducted to determine the flight characteristics of a representative STOL transport having a high wing and equipped with an external-flow jet flap in combination with four high-bypass-ratio fan-jet engines during the approach and landing. Real-time digital simulation techniques were used. The computer was programed with equations of motion for six degrees of freedom and the aerodynamic inputs were based on measured wind-tunnel data. A visual display of a STOL airport was provided for simulation of the flare and touchdown characteristics. The primary piloting task was an instrument approach to a breakout at a 200-ft ceiling with a visual landing