Integrated Flight and Propulsion Control for Novel Rotorcraft

Distributed Electric Propulsion (DEP) has increased the design space for aerospace vehicles, especially those categorized as eVTOL (Electric Vertical Take-Off and Landing). This new class of vehicles not only looks different from the typical airplane or helicopter, but functions differently as well. A robust understanding of how the vehicle is controlled in both nominal and off-nominal modes will frame the approach to certification for private and commercial VTOL aircraft. Embry-Riddle Aeronautical University’s Eagle Flight Research Center (EFRC) is researching how the various methods of DEP thrust control apply to larger eVTOL vehicle operation. Researchers will utilize a mixture of flight dynamic simulation and physical testing in collaboration with FAA experts in rotorcraft handling qualities certification. Outcomes of the research include the characterization of various DEP thrust and moment control methods and how this maps to certifiable vehicle-level attributes like handling qualities in nominal and degraded flight modes. A prototype will be built and tested showing the ability of a quad-rotor vehicle to continue flight after the loss of thrust by failure of one rotor. It is anticipated that a better understanding of the DEP units will help inform the process of certification for the emerging market of urban air mobility vehicles. The data obtained from testing will be utilized to define the possible performance parameters, which will aid in developing appropriate means of compliance for advanced fly-by-wire N-rotor eVTOL vehicles

Development of ERAU VOLTRON Hybrid-Electric Powerplant

The energy density of today’s batteries is not high enough for electric powered aircraft to achieve an operationally viable range plus FAA stipulated reserve flight times. Hybrid-electric power generation systems may be able to bridge the gap, providing a way for these aircraft to fly distances not possible with batteries alone. There is a recognition that gasoline-electric hybrid systems can deliver specific energy and specific power that are higher than any currently available battery system. Embry-Riddle Aeronautical University’s (ERAU’s) Eagle Flight Research Center (EFRC) is building a 70+ kW hybrid-electric power generation system using a rotary engine and Permanent Magnet Synchronous Machine (PMSM) & Inverter. The rotary engine will be directly coupled to the PMSM which will generate electrical energy to power multi-rotor eVTOL vehicles. These results will be achieved by utilizing advanced control systems implemented on a National Instruments Compact RIO. Past research conducted at the EFRC demonstrated the ability to design and operate a hybrid-electric powerplant. The VOLTRON project will attempt to create a system with an even higher specific energy but with the compact size and high power characteristics of a rotary engine and eventually alternative fuel flexibility

The chaperone protein clusterin may serve as a cerebrospinal fluid biomarker for chronic spinal cord disorders in the dog

Chronic spinal cord dysfunction occurs in dogs as a consequence of diverse aetiologies, including long-standing spinal cord compression and insidious neurodegenerative conditions. One such neurodegenerative condition is canine degenerative myelopathy (DM), which clinically is a challenge to differentiate from other chronic spinal cord conditions. Although the clinical diagnosis of DM can be strengthened by the identification of the Sod1 mutations that are observed in affected dogs, genetic analysis alone is insufficient to provide a definitive diagnosis. There is a requirement to identify biomarkers that can differentiate conditions with a similar clinical presentation, thus facilitating patient diagnostic and management strategies. A comparison of the cerebrospinal fluid (CSF) protein gel electrophoresis profile between idiopathic epilepsy (IE) and DM identified a protein band that was more prominent in DM. This band was subsequently found to contain a multifunctional protein clusterin (apolipoprotein J) that is protective against endoplasmic reticulum (ER) stress-mediated apoptosis, oxidative stress, and also serves as an extracellular chaperone influencing protein aggregation. Western blot analysis of CSF clusterin confirmed elevated levels in DM compared to IE (p < 0.05). Analysis of spinal cord tissue from DM and control material found that clusterin expression was evident in neurons and that the clusterin mRNA levels from tissue extracts were elevated in DM compared to the control. The plasma clusterin levels was comparable between these groups. However, a comparison of clusterin CSF levels in a number of neurological conditions found that clusterin was elevated in both DM and chronic intervertebral disc disease (cIVDD) but not in meningoencephalitis and IE. These findings indicate that clusterin may potentially serve as a marker for chronic spinal cord disease in the dog; however, additional markers are required to differentiate DM from a concurrent condition such as cIVDD

Follicle Stimulating Hormone is an accurate predictor of azoospermia in childhood cancer survivors

Funding: RTM is supported by a Wellcome Trust Intermediate Clinical Fellowship (grant no: 098522), https://wellcome.ac.uk/what-we-do/directories/intermediate-clinical-fellowships-people-funded. TWK is supported by Engineering and Physical Sciences Research Council grant EP/P015638/1, http://gow.epsrc.ac.uk/NGBOViewGrant.aspx?GrantRef=EP/P015638/1.The accuracy of Follicle Stimulating Hormone as a predictor of azoospermia in adult survivors of childhood cancer is unclear, with conflicting results in the published literature. A systematic review and post hoc analysis of combined data (n = 367) were performed on all published studies containing extractable data on both serum Follicle Stimulating Hormone concentration and semen concentration in survivors of childhood cancer. PubMed and Medline databases were searched up to March 2017 by two blind investigators. Articles were included if they contained both serum FSH concentration and semen concentration, used World Health Organisation certified methods for semen analysis, and the study participants were all childhood cancer survivors. There was no evidence for either publication bias or heterogeneity for the five studies. For the combined data (n = 367) the optimal Follicle Stimulating Hormone threshold was 10.4 IU/L with specificity 81% (95% CI 76%–86%) and sensitivity 83% (95% CI 76%–89%). The AUC was 0.89 (95%CI 0.86–0.93). A range of threshold FSH values for the diagnosis of azoospermia with their associated sensitivities and specificities were calculated. This study provides strong supporting evidence for the use of serum Follicle Stimulating Hormone as a surrogate biomarker for azoospermia in adult males who have been treated for childhood cancer.Publisher PDFPeer reviewe

The evolution of pyrimethamine resistant dhfr in Plasmodium falciparum of south-eastern Tanzania: comparing selection under SP alone vs SP+artesunate combination

BACKGROUND\ud \ud Sulphadoxine-pyrimethamine (SP) resistance is now widespread throughout east and southern Africa and artemisinin compounds in combination with synthetic drugs (ACT) are recommended as replacement treatments by the World Health Organization (WHO). As well as high cure rates, ACT has been shown to slow the development of resistance to the partner drug in areas of low to moderate transmission. This study looked for evidence of protection of the partner drug in a high transmission African context. The evaluation was part of large combination therapy pilot implementation programme in Tanzania, the Interdisciplinary Monitoring Programme for Antimalarial Combination Therapy (IMPACT-TZ) METHODS: The growth of resistant dhfr in a parasite population where SP Monotherapy was the first-line treatment was measured for four years (2002-2006), and compared with the development of resistant dhfr in a neighbouring population where SP + artesunate (SP+AS) was used as the first-line treatment during the same interval. The effect of the differing treatment regimes on the emergence of resistance was addressed in three ways. First, by looking at the rate of increase in frequency of pre-existing mutant dhfr alleles under monotherapy and combination therapy. Second, by examining whether de-novo mutant alleles emerged under either treatment. Finally, by measuring diversity at three dhfr flanking microsatellite loci upstream of the dhfr gene.\ud \ud RESULTS\ud \ud The reduction in SP selection pressure resulting from the adoption of ACT slowed the rate of increase in the frequency of the triple mutant resistant dhfr allele. Comparing between the two populations, the higher levels of genetic diversity in sequence flanking the dhfr triple mutant allele in the population where the ACT regimen had been used indicates the reduction in SP selection pressure arising from combination therapy.\ud \ud CONCLUSION\ud \ud The study demonstrated that, alleles containing two mutations at the dhfr have arisen at least four times independently while those containing triple mutant dhfr arose only once, and were found carrying a single unique Asian-type flanking sequence, which apparently drives the spread of pyrimethamine resistance associated dhfr alleles in east Africa. SP+AS is not recommended for use in areas where SP cure rates are less than 80% but this study reports an observed principle of combination protection from an area where pyrimethamine resistance was already high

Validation and Use of 22Na Turnover to Measure Food Intake in Free-Ranging Lizards

As the food intake of free-ranging animals has proved to be difficult to measure by traditional means, the feasibility of using radioactive Na to measure food consumption in a small scincid lizard (Lampropholis guichenoti) was assessed. This technique has previously been used only for several species of mammal. A significant relationship between food intake and Na turnover was found in the laboratory, with Na turnover underestimating intake by 7.6%. The food intake of free-ranging members of a field population was estimated by 22Na turnover to be 9.55, 0.65, 9.39 and 13.75 mg dry weight (day)-1 during autumn, winter, spring and summer respectively. Estimates of assimilated and expended energy from these food intake values agree closely with data reported for other lizards using alternative techniques. This study also describes the technical innovations which were necessary to study lizards weighing less than 1 g; and it suggests that 22Na can provide an easy, reliable and inexpensive means of studying the energetics of many free-living animals

Mapping Migratory Bird Prevalence Using Remote Sensing Data Fusion

This is the publisher’s final pdf. The published article is copyrighted by the Public Library of Science and can be found at: http://www.plosone.org/home.action.Background: Improved maps of species distributions are important for effective management of wildlife under increasing anthropogenic pressures. Recent advances in lidar and radar remote sensing have shown considerable potential for mapping forest structure and habitat characteristics across landscapes. However, their relative efficacies and integrated use in habitat mapping remain largely unexplored. We evaluated the use of lidar, radar and multispectral remote sensing data in predicting multi-year bird detections or prevalence for 8 migratory songbird species in the unfragmented temperate deciduous forests of New Hampshire, USA. \ud \ud Methodology and Principal Findings: A set of 104 predictor variables describing vegetation vertical structure and variability from lidar, phenology from multispectral data and backscatter properties from radar data were derived. We tested the accuracies of these variables in predicting prevalence using Random Forests regression models. All data sets showed more than 30% predictive power with radar models having the lowest and multi-sensor synergy ("fusion") models having highest accuracies. Fusion explained between 54% and 75% variance in prevalence for all the birds considered. Stem density from discrete return lidar and phenology from multispectral data were among the best predictors. Further analysis revealed different relationships between the remote sensing metrics and bird prevalence. Spatial maps of prevalence were consistent with known habitat preferences for the bird species. \ud \ud Conclusion and Significance: Our results highlight the potential of integrating multiple remote sensing data sets using machine-learning methods to improve habitat mapping. Multi-dimensional habitat structure maps such as those generated from this study can significantly advance forest management and ecological research by facilitating fine-scale studies at both stand and landscape level

Drug education in victorian schools (DEVS): the study protocol for a harm reduction focused school drug education trial

<p>Abstract</p> <p>Background</p> <p>This study seeks to extend earlier Australian school drug education research by developing and measuring the effectiveness of a comprehensive, evidence-based, harm reduction focused school drug education program for junior secondary students aged 13 to 15 years. The intervention draws on the recent literature as to the common elements in effective school curriculum. It seeks to incorporate the social influence of parents through home activities. It also emphasises the use of appropriate pedagogy in the delivery of classroom lessons.</p> <p>Methods/Design</p> <p>A cluster randomised school drug education trial will be conducted with 1746 junior high school students in 21 Victorian secondary schools over a period of three years. Both the schools and students have actively consented to participate in the study. The education program comprises ten lessons in year eight (13-14 year olds) and eight in year nine (14-15 year olds) that address issues around the use of alcohol, tobacco, cannabis and other illicit drugs. Control students will receive the drug education normally provided in their schools. Students will be tested at baseline, at the end of each intervention year and also at the end of year ten. A self completion questionnaire will be used to collect information on knowledge, patterns and context of use, attitudes and harms experienced in relation to alcohol, tobacco, cannabis and other illicit drug use. Multi-level modelling will be the method of analysis because it can best accommodate hierarchically structured data. All analyses will be conducted on an Intent-to-Treat basis. In addition, focus groups will be conducted with teachers and students in five of the 14 intervention schools, subsequent to delivery of the year eight and nine programs. This will provide qualitative data about the effectiveness of the lessons and the relevance of the materials.</p> <p>Discussion</p> <p>The benefits of this drug education study derive both from the knowledge gained by trialling an optimum combination of innovative, harm reduction approaches with a large, student sample, and the resultant product. The research will provide better understanding of what benefits can be achieved by harm reduction education. It will also produce an intervention, dealing with both licit and illicit drug use that has been thoroughly evaluated in terms of its efficacy, and informed by teacher and student feedback. This makes available to schools a comprehensive drug education package with prevention characteristics and useability that are well understood.</p> <p>Trial registration</p> <p>Australia and New Zealand Clinical Trials Register (ANZCTR): <a href="http://www.anzctr.org.au/ACTRN12612000079842.aspx">ACTRN12612000079842</a></p

Cisplatin and Doxorubicin Induce Distinct Mechanisms of Ovarian Follicle Loss; Imatinib Provides Selective Protection Only against Cisplatin

Chemotherapy treatment in premenopausal women has been linked to ovarian follicle loss and premature ovarian failure; the exact mechanism by which this occurs is uncertain. Here, two commonly used chemotherapeutic agents (cisplatin and doxorubicin) were added to a mouse ovary culture system, to compare the sequence of events that leads to germ cell loss. The ability of imatinib mesylate to protect the ovary against cisplatin or doxorubicin-induced ovarian damage was also examined.Newborn mouse ovaries were cultured for a total of six days, exposed to a chemotherapeutic agent on the second day: this allowed for the examination of the earliest stages of follicle development. Cleaved PARP and TUNEL were used to assess apoptosis following drug treatment. Imatinib was added to cultures with cisplatin and doxorubicin to determine any protective effect.Histological analysis of ovaries treated with cisplatin showed oocyte-specific damage; in comparison doxorubicin preferentially caused damage to the granulosa cells. Cleaved PARP expression significantly increased for cisplatin (16 fold, p<0.001) and doxorubicin (3 fold, p<0.01). TUNEL staining gave little evidence of primordial follicle damage with either drug. Imatinib had a significant protective effect against cisplatin-induced follicle damage (p<0.01) but not against doxorubicin treatment.Cisplatin and doxorubicin both induced ovarian damage, but in a markedly different pattern, with imatinib protecting the ovary against damage by cisplatin but not doxorubicin. Any treatment designed to block the effects of chemotherapeutic agents on the ovary may need to be specific to the drug(s) the patient is exposed to