Kinematic properties of the helicopter in coordinated turns

A study on the kinematic relationship of the variables of helicopter motion in steady, coordinated turns involving inherent sideslip is described. A set of exact kinematic equations which govern a steady coordinated helical turn about an Earth referenced vertical axis is developed. A precise definition for the load factor parameter that best characterizes a coordinated turn is proposed. Formulas are developed which relate the aircraft angular rates and pitch and roll attitudes to the turn parameters, angle of attack, and inherent sideslip. A steep, coordinated helical turn at extreme angles of attack with inherent sideslip is of primary interest. The bank angle of the aircraft can differ markedly from the tilt angle of the normal load factor. The normal load factor can also differ substantially from the accelerometer reading along the vertical body axis of the aircraft. Sideslip has a strong influence on the pitch attitude and roll rate of the helicopter. Pitch rate is independent of angle of attack in a coordinated turn and in the absence of sideslip, angular rates about the stability axes are independent of the aerodynamic characteristics of the aircraft

Vertical yoked prisms affect standing center of balance

This experiment was designed to determine the effect of vertically yoked prisms on standing balance. The BALANCE SYSTEM from Chattecx Corporation was utilized to quantify center of balance position in the leftward or rightward direction, forward or rearward direction, and the amount of variability in position, postural sway. Test lenses for the conditions of plano, 12 prism diopters yoked bases-up, and 12 prism diopters yoked bases-down were fitted over the habitual lens prescriptions of 36 young adult subjects with normal vision. Pressure sensitive transducers under the ball and heel of each foot provided data at a rate of 100 samples per second during two 10-second test periods; 0-10 sec and 30-40 sec immediately after opening the eyes and fixating a muscle light at 5 meters. No differences in right/Ieft center of balance. were found in any comparative analysis. Instrument test-retest reliability was established during the 0 to 10 sec time period for right/Ieft center of balance, forward/rearward center of balance and postural sway. Differences in forward/rearward center of balance occurred during the 30 to 40 sec time period. Significant rearward shifts occurred with base-down yoked prisms when compared to base-up and plano during both the 0-1 0 sec and 30-40 sec periods. Significant increases in postural sway occurred with base-down compared with plano during the 0-10 sec epoch and base-up compared to plano during the 3D-40 sec epoch. During post-prism plano conditions, significant rearward shifts occurred With post-base-up plano and post-base-down plano compared to plano during the 30 to 40 sec period. Additionally, post-prism plano conditions showed a significant increase in postural sway during 0 to ~ 0 sec and the 30 to 40 sec periods. During the 0 to 10 sec period immediately after opening eyes, objective measurement indicates base-down vertically yoked prisms produce a significant rearward shift in and increased postural sway when compared to plano lenses. These results further support vision\u27s strong role in standing balance

Defending against Sybil Devices in Crowdsourced Mapping Services

Real-time crowdsourced maps such as Waze provide timely updates on traffic, congestion, accidents and points of interest. In this paper, we demonstrate how lack of strong location authentication allows creation of software-based {\em Sybil devices} that expose crowdsourced map systems to a variety of security and privacy attacks. Our experiments show that a single Sybil device with limited resources can cause havoc on Waze, reporting false congestion and accidents and automatically rerouting user traffic. More importantly, we describe techniques to generate Sybil devices at scale, creating armies of virtual vehicles capable of remotely tracking precise movements for large user populations while avoiding detection. We propose a new approach to defend against Sybil devices based on {\em co-location edges}, authenticated records that attest to the one-time physical co-location of a pair of devices. Over time, co-location edges combine to form large {\em proximity graphs} that attest to physical interactions between devices, allowing scalable detection of virtual vehicles. We demonstrate the efficacy of this approach using large-scale simulations, and discuss how they can be used to dramatically reduce the impact of attacks against crowdsourced mapping services.Comment: Measure and integratio

Dual-probe decoherence microscopy: Probing pockets of coherence in a decohering environment

We study the use of a pair of qubits as a decoherence probe of a non-trivial environment. This dual-probe configuration is modelled by three two-level-systems which are coupled in a chain in which the middle system represents an environmental two-level-system (TLS). This TLS resides within the environment of the qubits and therefore its coupling to perturbing fluctuations (i.e. its decoherence) is assumed much stronger than the decoherence acting on the probe qubits. We study the evolution of such a tripartite system including the appearance of a decoherence-free state (dark state) and non-Markovian behaviour. We find that all parameters of this TLS can be obtained from measurements of one of the probe qubits. Furthermore we show the advantages of two qubits in probing environments and the new dynamics imposed by a TLS which couples to two qubits at once.Comment: 29 pages, 10 figure

Androgen receptor genotyping in a large Australasian cohort with androgen insensitivity syndrome; identification of four novel mutations

We genotyped the androgen receptor (AR) gene in 31 Australasian patients with androgen insensitivity syndrome (AIS). The entire coding region of AR was examined including analysis of polymorphic CAG and GGN repeats in all patients. AR defects were found in 66.7% (6/9) of patients with complete AIS (CAIS) and 13.6% (3/22) of patients with partial AIS (PAIS). A novel deletion (N858delG) leading to a premature stop codon was found in CAIS patient P1. CAIS patient P2 has a novel deletion (N2676delGAGT) resulting in a stop at codon 787. These mutations would result in inactivation of AR protein. A novel insertion of a cysteine residue in the first zinc finger of the AR DNA-binding domain (N2045_2047dupCTG) was found in CAIS patient P3. PAIS patient P4 has a novel amino acid substitution (Arg760Ser) in the AR ligand binding domain, which may impair ligand binding. Five patients were found to have previously reported AR mutations and no mutations were identified in the remaining patients

Age-related changes in T lymphocytes of patients with head and neck squamous cell carcinoma

Introduction The number of aging cancer patients has increased continuously and will do so further in the future. The immune system of elderly people experiences critical changes over the time. Therefore, tumor-induced changes in the immune system are believed to differ in young and elderly cancer patients as well. Methods The effect of aging on the immune system was measured in peripheral blood lymphocytes (PBL) of healthy volunteers (n = 48, 21–84 yrs.) divided into three different age groups. Seventy years was set as a cut-off for defining subjects as elderly. Results were compared to two groups of adult cancer patients, which donated PBL and tumor infiltrating lymphocytes (TIL): young cancer patients (40–69 yrs.; blood: n = 13; TIL: n = 17) and elderly cancer patients (70–90 yrs.; blood: n = 20; TIL: n = 15) with head and neck squamous cell carcinoma (HNSCC). Frequencies and phenotypes of CD4+ and CD8+ T cells as well as regulatory T cells (Treg) were assessed by flow cytometry. Results We observed lower frequencies of CD8+ cytotoxic T cells during aging in both groups. Frequencies of tumor infiltrating regulatory T cells were significantly higher than in the peripheral blood but showed a significant decline in older tumor patients. With increasing age, expression of immunosuppressive CD73 and CCR7 was lower and expression of PD1 elevated on peripheral T cells in healthy volunteers and tumor patients. Conclusion Immunosenescence takes place in healthy donors and cancer patients. Our results suggest that in elderly tumor patients, the immune system is impaired and the tumor-induced immune escape is less pronounced. The increased expression of PD1 implies the potential for effective immunotherapies in elderly, as treatment with checkpoint inhibitors could be more beneficial for elderly HNSCC patients

Exploring the impact of a complex intervention for women with depression in contexts of adversity: A pilot feasibility study of COURRAGE-plus in South Africa.

BACKGROUND: Depression is a leading cause of disease burden worldwide but is often undertreated in low- and middle-income countries. Reasons behind the treatment gap vary, but many highlight a lack of interventions which speak to the socio-economic and structural realties that are associated to mental health problems in many settings, including South Africa. The COURRAGE-PLUS intervention responds to this gap, by combining a collective narrative therapy (9 weeks) intervention, with a social intervention promoting group-led practical action against structural determinants of poor mental health (4 weeks), for a total of 13 sessions. The overall aim is to promote mental health, while empowering communities to acknowledge, and respond in locally meaningful ways to social adversity linked to development of mental distress. AIM: To pilot and evaluate the effectiveness of a complex intervention - COURRAGE-PLUS on symptoms of depression as assessed by the Patient Health Questionnaire (PHQ-9) among a sample of women facing contexts of adversity in Gauteng, South Africa. METHODS: PHQ-9 scores were assessed at baseline, post collective narrative therapy (midline), and post social intervention (endline). Median scores and corresponding interquartile ranges were computed for all time points. Differences in scores between time points were tested with a non-parametric Friedman test. The impact across symptom severities was compared descriptively to identify potential differences in impact across categories of symptom severity within our sample. RESULTS: Participants' (n = 47) median depression score at baseline was 11 (IQR = 7) and reduced to 4 at midline (IQR = 7) to 0 at endline (IQR = 2.5). The Friedman test showed a statistically significant difference between depression scores across time points, χ 2 (2) = 49.29, p < .001. Median depression scores were reduced to 0 or 1 Post-Intervention across all four severity groups. CONCLUSIONS: COURRAGE-PLUS was highly effective at reducing symptoms of depression across the spectrum of severities in this sample of women facing adversity, in Gauteng, South Africa. Findings supports the need for larger trials to investigate collective narrative storytelling and social interventions as community-based interventions for populations experiencing adversity and mental distress

Analysis of bacterial communities in a municipal duck pond during a phytoplankton bloom and isolation of Anatilimnocola aggregata gen. nov., sp. nov., Lacipirellula limnantheis sp. nov. and Urbifossiella limnaea gen. nov., sp. nov. belonging to the phylum Planctomycetes

Waterbodies such as lakes and ponds are fragile environments affected by human influences. Suitable conditions can result in massive growth of phototrophs, commonly referred to as phytoplankton blooms. Such events benefit heterotrophic bacteria able to use compounds secreted by phototrophs or their biomass as major nutrient source. One example of such bacteria are Planctomycetes, which are abundant on the surfaces of marine macroscopic phototrophs; however, less data are available on their ecological roles in limnic environments. In this study, we followed a cultivation-independent deep sequencing approach to study the bacterial community composition during a cyanobacterial bloom event in a municipal duck pond. In addition to cyanobacteria, which caused the bloom event, members of the phylum Planctomycetes were significantly enriched in the cyanobacteria-attached fraction compared to the free-living fraction. Separate datasets based on isolated DNA and RNA point towards considerable differences in the abundance and activity of planctomycetal families, indicating different activity peaks of these families during the cyanobacterial bloom. Motivated by the finding that the sampling location harbours untapped bacterial diversity, we included a complementary cultivation-dependent approach and isolated and characterized three novel limnic strains belonging to the phylum Planctomycetes