Fast and Noise-Resilient Magnetic Field Mapping on a Low-Cost UAV Using Gaussian Process Regression.

This study presents a comprehensive approach to mapping local magnetic field anomalies with robustness to magnetic noise from an unmanned aerial vehicle (UAV). The UAV collects magnetic field measurements, which are used to generate a local magnetic field map through Gaussian process regression (GPR). The research identifies two categories of magnetic noise originating from the UAV's electronics, adversely affecting map precision. First, this paper delineates a zero-mean noise arising from high-frequency motor commands issued by the UAV's flight controller. To mitigate this noise, the study proposes adjusting a specific gain in the vehicle's PID controller. Next, our research reveals that the UAV generates a time-varying magnetic bias that fluctuates throughout experimental trials. To address this issue, a novel compromise mapping technique is introduced, enabling the map to learn these time-varying biases with data collected from multiple flights. The compromise map circumvents excessive computational demands without sacrificing mapping accuracy by constraining the number of prediction points used for regression. A comparative analysis of the magnetic field maps' accuracy and the spatial density of observations employed in map construction is then conducted. This examination serves as a guideline for best practices when designing trajectories for local magnetic field mapping. Furthermore, the study presents a novel consistency metric intended to determine whether predictions from a GPR magnetic field map should be retained or discarded during state estimation. Empirical evidence from over 120 flight tests substantiates the efficacy of the proposed methodologies. The data are made publicly accessible to facilitate future research endeavors.

Identification of quantitative trait nucleotides and candidate genes for tuber yield and mosaic virus tolerance in an elite population of white guinea yam (Dioscorea rotundata) using genome-wide association scan.

BACKGROUND: Improvement of tuber yield and tolerance to viruses are priority objectives in white Guinea yam breeding programs. However, phenotypic selection for these traits is quite challenging due to phenotypic plasticity and cumbersome screening of phenotypic-induced variations. This study assessed quantitative trait nucleotides (QTNs) and the underlying candidate genes related to tuber yield per plant (TYP) and yam mosaic virus (YMV) tolerance in a panel of 406 white Guinea yam (Dioscorea rotundata) breeding lines using a genome-wide association study (GWAS). RESULTS: Population structure analysis using 5,581 SNPs differentiated the 406 genotypes into seven distinct sub-groups based delta K. Marker-trait association (MTA) analysis using the multi-locus linear model (mrMLM) identified seventeen QTN regions significant for TYP and five for YMV with various effects. The seveteen QTNs were detected on nine chromosomes, while the five QTNs were identified on five chromosomes. We identified variants responsible for predicting higher yield and low virus severity scores in the breeding panel through the marker-effect prediction. Gene annotation for the significant SNP loci identified several essential putative genes associated with the growth and development of tuber yield and those that code for tolerance to mosaic virus. CONCLUSION: Application of different multi-locus models of GWAS identified 22 QTNs. Our results provide valuable insight for marker validation and deployment for tuber yield and mosaic virus tolerance in white yam breeding. The information on SNP variants and genes from the present study would fast-track the application of genomics-informed selection decisions in breeding white Guinea yam for rapid introgression of the targeted traits through markers validation.

Improving Attitude Estimation Using Gaussian-Process-Regression-Based Magnetic Field Maps.

Magnetometers measure the local magnetic field and are present in most modern inertial measurement units (IMUs). Readings from magnetometers are used to identify Earth's Magnetic North outdoors, but are often ignored during indoor experiments since the magnetic field does not behave how most expect. This paper presents methods to create, validate, and visualize three-dimensional magnetic field maps to expand the use of magnetic fields as a sensing modality for navigation. The utility of these maps is measured in their ability to accurately represent the magnetic field and to enable dynamic attitude estimation. In experiments with motion capture truth data, a small multicopter with three-axis inertial measurements, including magnetometer, traversed five flight profiles distinctly exciting roll, pitch, and yaw motion to provide interesting trajectories for attitude estimation. Indoor experimental results were compared to those outdoors to emphasize how spatial variation in the magnetic field drives the need for our mapping techniques. Our work presents a new way of visualizing 3D magnetic fields, which allows users to better reason about the magnetic field in their workspace. Next, we show that magnetic field maps generated from coverage patterns are generally more accurate, but training such maps using observations from desired flight paths is sufficient in the vicinity of these paths. All training sets were interpolated using Gaussian process regression (GPR), which yielded maps with <1 µT of error when interpolating between and extrapolating outside of observed locations. Finally, we validated the utility of our GPR-based maps in enabling attitude estimates in regions of high magnetic field spatial variation with experimental data.

Genetic characterization of cassava (Manihot esculenta Crantz) genotypes using agro-morphological and single nucleotide polymorphism markers.

Dearth of information on extent of genetic variability in cassava limits the genetic improvement of cassava genotypes in Sierra Leone. The aim of this study was to assess the genetic diversity and relationships within 102 cassava genotypes using agro-morphological and single nucleotide polymorphism markers. Morphological classification based on qualitative traits categorized the germplasm into five different groups, whereas the quantitative trait set had four groups. The SNP markers classified the germplasm into three main cluster groups. A total of seven principal components (PCs) in the qualitative and four PCs in the quantitative trait sets accounted for 79.03% and 72.30% of the total genetic variation, respectively. Significant and positive correlations were observed between average yield per plant and harvest index (r = 0.76***), number of storage roots per plant and harvest index (r = 0.33*), height at first branching and harvest index (0.26*), number of storage roots per plant and average yield per plant (r = 0.58*), height at first branching and average yield per plant (r = 0.24*), length of leaf lobe and petiole length (r = 0.38*), number of leaf lobe and petiole length (r = 0.31*), width of leaf lobe and length of leaf lobe (r = 0.36*), number of leaf lobe and length of leaf lobe (r = 0.43*), starch content and dry matter content (r = 0.99***), number of leaf lobe and root dry matter (r = 0.30*), number of leaf lobe and starch content (r = 0.28*), and height at first branching and plant height (r = 0.45**). Findings are useful for conservation, management, short term recommendation for release and genetic improvement of the crop.

Exploring the impact of therapeutic advances in HIV-related mortality in the United States.

Objectives: Mortality from HIV has significantly declined with the introduction of highly active antiretroviral therapy (HAART). This study sought to examine the longitudinal trends in mortality from HIV-related diseases by race, sex, geographical region, and over time as HAART trends changed. Methods: We queried the Centers for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research database and performed serial cross-sectional analyses of national death certificate data for all-cause mortality with comorbid HIV from 1999 to 2020. HIV diseases (International Classification of Diseases, Tenth Revision codes B20-B24, O98.7, R75) were listed as the contributing cause of death. We calculated the age-adjusted mortality ratio (AAMR) per 1,000,000 individuals and determined mortality trends using the Joinpoint Regression Program. Subgroup analyses were performed by sex, race, region, and organ system. The study period was further stratified into three groups when specific drug regimens were more prevalent. Results: In the 22-year study period, 251,759 all-cause mortalities with comorbid HIV were identified. The leading cause of death was infectious disease (84.0%, N = 211,438). Men recorded a higher AAMR than women (4.66 vs 1.65, P < 0.01). African American individuals had the highest AAMR (13.46) compared to White, American Indian, and Asian individuals (1.70 vs 1.65 vs 0.47). The South region had the highest AAMR (4.32) and urban areas had a higher AAMR compared to rural areas (1.77 vs 0.88). Conclusions: More than 80% of deaths occurred because of infectious disease over the last 2 decades with a decreasing trend over time when stratified by race, sex, and geographical region. Despite advances in HAART, mortality disparities persist which emphasizes the need for targeted interventions in these populations.

The involvement of parents in healthcare decisions where adult children are at risk of lacking decision-making capacity: a qualitative study of treatment decisions in epilepsy.

BACKGROUND: Patients with intellectual disabilities (ID) receive health care by proxy. It is family members and/or paid support staff who must recognise health problems, communicate with clinicians, and report the benefits, if any, of a particular treatment. At the same time international and national statutes protect and promote the right of people with disabilities to access the highest attainable standards of health on the basis of free and informed consent. METHODS: To consider the role of parent-proxies in the management of epilepsy in adult children with ID who are at risk of lacking capacity to make decisions about their health care we interviewed 21 mothers. FINDINGS: These mothers are not pursuing changes in treatment that might improve their son or daughter's epilepsy, nor are they willing to countenance changes in treatment. Clinicians concerned to build and sustain therapeutic alliances with these mothers, our evidence suggests, may well avoid going against their wishes. DISCUSSION: Our research highlights the interactional contingencies of a hitherto neglected three-way clinical relationship comprising parent-proxy, an adult at risk of lacking decision-making capacity, and a treating clinician. This is a relationship, our findings suggest, where little importance is attached to either patient consent, or involvement in treatment decisions.

Cost-Effectiveness Analysis of Myopia Progression Interventions in Children.

Importance: Several interventions exist for treating myopia progression in children. While these interventions' efficacy has been studied, their cost-effectiveness remains unknown and has not been compared. Objective: To determine cost-effective options for controlling myopia progression in children. Design, Setting, and Participants: In this cost-effectiveness analysis, a Markov model was designed to compare the cost-effectiveness of interventions for controlling myopia progression over 5 years from a societal perspective in a simulated hypothetical cohort of patients aged 10 years with myopia. Myopia interventions considered included atropine eye drops, 0.05% and 0.01%, defocus incorporated multiple segment spectacles, outdoor activity, soft contact lenses (daily disposable and multifocal), rigid gas-permeable contact lenses, progressive addition lenses, bifocal spectacle lenses, orthokeratology, highly aspherical lenslets (HALs), and red light therapy; all interventions were compared with single-vision lenses. Deterministic and probabilistic sensitivity analysis determined the association of model uncertainties with the cost-effectiveness. Costs were obtained from the charges of the Hospital Authority of Hong Kong and The Chinese University of Hong Kong Eye Center. Main Outcome and Measures: The mean costs (in US dollars) per child included the cost of hospital visits, medications, and optical lenses. The outcomes of effectiveness were the annual spherical equivalent refraction (SER) and axial length (AL) reductions. Incremental cost-effectiveness ratios (ICERs) were calculated for each strategy relative to single-vision lenses over a time horizon of 5 years. Results: Outdoor activity, atropine (0.05%), red light therapy, HALs, and orthokeratology were cost-effective. The ICER of atropine, 0.05%, was US $220/SER reduction; red light therapy, US $846/SER reduction; and HALs, US $448/SER reduction. Outdoor activity yielded a savings of US $5/SER reduction and US $8/AL reduction. Orthokeratology resulted in an ICER of US $2376/AL reduction. Conclusions and Relevance: These findings suggest that atropine eye drops, 0.05%, and outdoor activity are cost-effective for controlling myopia progression in children. Though more expensive, red light therapy, HALs, and orthokeratology may also be cost-effective. The use of these interventions may help to control myopia in a cost-effective way.

Paternity Assignment in White Guinea Yam (Dioscorea Rotundata) Half-Sib Progenies from Polycross Mating Design Using SNP Markers.

White Guinea yam is mostly a dioecious outcrossing crop with male and female flowers produced on distinct plants. Fertile parents produce high fruit set in an open pollination polycross block, which is a cost-effective and convenient way of generating variability in yam breeding. However, the pollen parent of progeny from polycross mating is usually unknown. This study aimed to determine paternity in white Guinea yam half-sib progenies from polycross mating design. A total of 394 half-sib progenies from random open pollination involving nine female and three male parents was genotyped with 6602 SNP markers from DArTSeq platform to recover full pedigree. A higher proportion of expected heterozygosity, allelic richness, and evenness were observed in the half-sib progenies. A complete pedigree was established for all progenies from two families (TDr1685 and TDr1688) with 100% accuracy, while in the remaining families, paternity was assigned successfully only for 56 to 98% of the progenies. Our results indicated unequal paternal contribution under natural open pollination in yam, suggesting unequal pollen migrations or gene flow among the crossing parents. A total of 3.8% of progenies lacking paternal identity due to foreign pollen contamination outside the polycross block was observed. This study established the efficient determination of parental reconstruction and allelic contributions in the white Guinea yam half-sib progenies generated from open pollination polycross using SNP markers. Findings are useful for parental reconstruction, accurate dissection of the genetic effects, and selection in white Guinea yam breeding program utilizing polycross mating design.

Migratory movements, depth preferences, and thermal biology of Atlantic bluefin tuna.

The deployment of electronic data storage tags that are surgically implanted or satellite-linked provides marine researchers with new ways to examine the movements, environmental preferences, and physiology of pelagic vertebrates. We report the results obtained from tagging of Atlantic bluefin tuna with implantable archival and pop-up satellite archival tags. The electronic tagging data provide insights into the seasonal movements and environmental preferences of this species. Bluefin tuna dive to depths of >1000 meters and maintain a warm body temperature. Western-tagged bluefin tuna make trans-Atlantic migrations and they frequent spawning grounds in the Gulf of Mexico and eastern Mediterranean. These data are critical for the future management and conservation of bluefin tuna in the Atlantic.

Bridging the research gap: aboriginal and academic collaboration in FASD prevention. The Healthy Communities, Mothers and Children Project.

OBJECTIVES: The objective was to assist with the prevention of Fetal Alcohol Spectrum Disorder through a participatory research approach involving local women and health care workers. Our interest was in understanding how well communities could develop culturally appropriate methods of helping women to reduce their alcohol consumption during pregnancy. STUDY DESIGN: Four geographically distant Aboriginal communities were presented with a task of adapting a standard Brief Alcohol Intervention, and in particular to develop a culturally appropriate means of using the Intervention with women in the community. METHODS: Academic and Aboriginal community researchers worked together in partnership, using a participatory action research approach to address alcohol use during pregnancy. RESULTS: The outcome of the project was the design of four differing models of culturally appropriate community interventions designed to support vulnerable women in their childbearing years. The intervention models developed by the four communities have five core characteristics: (1) identification of women at risk; (2) assessment of the woman's drinking/ drug use; (3) provision of information to the women; (4) delivery method facilitates the decision to adopt healthier behaviors; and (5) means to monitor changes. CONCLUSION: This project was considered successful in many respects: (1) each community developed a culturally-relevant prevention tool; (2) community involvement in the design lead to better understanding of its usefulness; (3) considerable knowledge exchange between academic and community partners took place; and (4) most importantly, it was found that community members can be active members in developing and implementing solutions to important public health issues.

Androgen deprivation and radiation therapy: sequencing studies using the Shionogi in vivo tumor system.

PURPOSE: To test the relative effect of neoadjuvant and adjuvant androgen deprivation on the radiation response of an androgen dependent tumor. METHODS AND MATERIALS: The transplantable, androgen dependent, Shionogi adenocarcinoma was grown as allografts in the hind limbs of NCr/Sed (nu/nu) athymic nude mice. Bilateral orchiectomy was the chosen form of androgen deprivation. Groups of tumors were irradiated to graded tumor doses and then studied for durable tumor control. The radiation response was expressed as the radiation dose required to control 50% of the tumors (TCD50). The sequence of radiation and orchiectomy was studied. RESULTS: When radiation was combined with orchiectomy the Shionogi tumor was significantly more likely to be controlled than when radiation was used alone. Orchiectomy 12 days prior to radiation (neoadjuvant therapy) produced a significantly greater decline in the TCD50 than when orchiectomy was used 1 day or 12 days after radiation (adjuvant therapy). If, before radiation, tumors were allowed to regrow after orchiectomy to their original size in an androgen independent fashion then the advantage was largely lost. Those tumors responding well to neoadjuvant orchiectomy (>50% volume decrease) were significantly more likely to be eradicated by radiation than those with a lesser response. CONCLUSION: When using combinations of androgen deprivation and radiation in the treatment of the Shionogi tumor, sequence and timing of the therapies are crucial to maximize the effect.

Neoadjuvant androgen suppression with radiation in the management of locally advanced adenocarcinoma of the prostate: experimental and clinical results.

Conventional radiotherapy has been a standard treatment for the management of locally advanced T2c-4 prostatic carcinoma for over 2 decades. The routine use of serum PSA in follow-up makes it clear that > 80% of these patients will show evidence of failure by 10 years. Rebiopsy of those with a rising PSA shows locally persistent disease in the majority of cases. Increasing the radiation dose applied to the prostate increases local control but at the risk of higher morbidity. Experimental data using the Shionogi tumor mouse model suggest a potential gain from neoadjuvant androgen suppression without any increase in normal tissue morbidity. Two randomized trials comparing neoadjuvant androgen suppression prior to radiation therapy with radiation alone in humans show considerable short-term gains in local control and disease-free survival but mature data are still awaited. It is currently unknown whether the positive interaction between radiation and androgen suppression is synergistic or simply additive.

An evaluation of the efficacy of Aqualox for microbiological control of industrial cooling tower systems.

A comprehensive sampling protocol was employed to evaluate the efficacy of Aqualox, a biocide based on electrochemically activated water, against legionellae and heterotrophic bacteria in two industrial cooling tower systems. Both of the towers in the study remained free from evidence of Legionella spp. contamination throughout a five-month evaluation period, despite the previously demonstrated presence of legionellae in one of the test towers, and in two other towers on the same site, at levels well in excess of UK Health and Safety Commission (HSC) Approved Code of Practice and Guidance (ACOP) upper action limits. Levels of heterotrophic bacteria were controlled below 10(4) cfu/mL in both towers throughout most of the trial. Results also provided indirect evidence of significant activity against biofilm bacteria, with biofilm removal beginning almost immediately after commissioning of the Aqualox treatment systems. The results were particularly encouraging as the two towers studied had a long history of poor microbiological control using conventional bromine-based biocide products. Significant differences were observed between laboratory measurements of total viable counts on frequent liquid samples and those obtained from dip slides following HSC recommendations.

Ab initio phase determination for X-ray diffraction data from crystals of a native protein.

An efficient algorithm for the determination of an everywhere positive electron-density distribution that agrees with observed structure amplitudes has been used to determine the phases of X-ray diffraction data from recombinant bovine chymosin, a protein with 323 amino-acid residues in the molecular chain whose structure was recently determined using molecular replacement methods. A systematic procedure for testing the signs of centric reflections, using the total entropy of the map as a figure of merit, was used to produce a low-resolution map. The phases of acentric and additional centric reflections were then chosen by adding them to the map with various possible phases and computing the total entropy of the resulting map. Of 159 centric reflections whose phases were chosen by this procedure, 141 had the same phase as in the refined structure. The median absolute phase difference for 1811 acentric reflections was 32 degrees. A map produced from these 1970 reflections, out of 12,346 reflections in the data set, showed a remarkable agreement with the refined structure. This molecule is many times larger than any whose structures have previously been determined without the use of isomorphous replacement, molecular replacement or anomalous dispersion, and the map demonstrates the potential of maximum-entropy methods in macromolecular structure determination.

Materials Research With Neutrons at NIST.

The NIST Materials Science and Engineering Laboratory works with industry, standards bodies, universities, and other government laboratories to improve the nation's measurements and standards infrastructure for materials. An increasingly important component of this effort is carried out at the NIST Center for Neutron Research (NCNR), at present the most productive center of its kind in the United States. This article gives a brief historical account of the growth and activities of the Center with examples of its work in major materials research areas and describes the key role the Center can expect to play in future developments.

Trends in treatment performed in the Phelophepa Dental Clinic: 1995-2000.

Mobile clinics are a cost-effective method of meeting the dental needs of rural communities in South Africa. Phelophepa, the first primary health care train of its kind world-wide, provides eye care, education, medicine, basic health care and since June 1995 dental treatment to rural communities. All services are rendered by students under supervision of qualified staff. The aim of this study was to analyse and report the data for treatment performed in the dental clinic from June 1995 to May 2000. During its first five years of operation, dental services were provided at 183 towns in all provinces except Gauteng. Of the 42,073 patients treated during this time (an average of 229.9 per town), 67.4% were adults. 71.3% of the 103,283 procedures performed were extractions, 15.7% could be classified as preventive with the remaining 13% as restorative procedures. The average value of the service provided to each patient was R218.53. The exposure of dental, dental therapy and oral hygiene students to rural areas of South Africa serves the important purpose of sensitising students to the realities of oral diseases in these communities.

Analysis of occlusal vertical dimension and mandibular Basal bone height in a nigerian population.

Background. The actual basal bone height of the reconstructed mandible is relevant to achieve normal occlusal vertical dimension for the prosthesis fabricated. The purpose of the study was to determine the mean and baseline values of the occlusal vertical dimension and height of the mandibular basal bone in a Nigerian population. Method. Each participant was asked to bring the upper and lower teeth into contact, while the distance between the nasal sill and dimple on the lower lip was measured (OVD). The skin at lower border of the mandible was marked and the distance between this point and the landmark on the lower lip was measured, MBH. Result. 200 subjects were evaluated. Age range was 16-30 years, mean ± (SD), 21.6 ± (3.1) years. Males had mean ± (SD) of 42.10 ± (5.34) mm for OVD and females 39.72 ± (5.25) mm; acceptable baseline range of OVD for any population will be 34-48 mm (3.4-4.8) cm. All the males had a mean ± (SD), 30.54 ± (6.13) mm for MBH, and all the females 29.63 ± (5.23) mm. Acceptable baseline range of MBH for any population will be 24-37 mm (2.4-3.7) cm. Conclusion. To reconstruct the mandible and still maintain the OVD, heights of bone grafts must not be less than 2 cm or greater than 4 cm.