Adaptive robotic system for the inspection of aerospace slat actuator mount.

Introduction: Robotics uptake in the aerospace industry is low, mainly due to the low-volume/high-accuracy production that aerospace manufacturers require. Furthermore, aerospace manufacturing and assembly sites are often unstructured environments not specifically suitable for robots to operate in. Methods: This paper introduces a robotic visual inspection system using off-the-shelf components able to inspect the mounting holes for wing slat actuators without the need for fixed-coordinate programming; the part just needs to be left within reach of the robot. Our system sets one of the opposed pairs of mounting holes as a reference (the "datum") and then compares the tilt of all other pairs of mounting holes with respect to it. Under the assumption that any deviation in the mounting hole tilt is not systematic but due to normal manufacturing tolerances, our system will either guarantee the correct alignment of all mounting holes or highlight the existence of misaligned holes. Results and Discussion: Computer-vision tilt measurements are performed with an error of below 0.03° using custom optimization for the sub-pixel determination of the center and radius of the mounting holes. The error introduced by the robot's motion from the datum to each of the remaining hole pairs is compensated by moving back to the datum and fixing the orientation again before moving to inspect the next hole pair. This error is estimated to be approximately 0.05°, taking the total tilt error estimation for any mounting hole pair to be 0.08° with respect to the datum. This is confirmed by manually measuring the tilt of the hole pairs using a clock gauge on a calibrated table (not used during normal operation).

Integrating Wireless Remote Sensing and Sensors for Monitoring Pesticide Pollution in Surface and Groundwater.

Water constitutes an indispensable resource crucial for the sustenance of humanity, as it plays an integral role in various sectors such as agriculture, industrial processes, and domestic consumption. Even though water covers 71% of the global land surface, governments have been grappling with the challenge of ensuring the provision of safe water for domestic use. A contributing factor to this situation is the persistent contamination of available water sources rendering them unfit for human consumption. A common contaminant, pesticides are not frequently tested for despite their serious effects on biodiversity. Pesticide determination in water quality assessment is a challenging task because the procedures involved in the extraction and detection are complex. This reduces their popularity in many monitoring campaigns despite their harmful effects. If the existing methods of pesticide analysis are adapted by leveraging new technologies, then information concerning their presence in water ecosystems can be exposed. Furthermore, beyond the advantages conferred by the integration of wireless sensor networks (WSNs), the Internet of Things (IoT), Machine Learning (ML), and big data analytics, a notable outcome is the attainment of a heightened degree of granularity in the information of water ecosystems. This paper discusses methods of pesticide detection in water, emphasizing the possible use of electrochemical sensors, biosensors, and paper-based sensors in wireless sensing. It also explores the application of WSNs in water, the IoT, computing models, ML, and big data analytics, and their potential for integration as technologies useful for pesticide monitoring in water.

A card-sorting tool to measure expert versus novice thinking in scientific research.

Undergraduate research and laboratory experiences provide a wide range of benefits to student learning in science and are integral to imbed authentic research experiences in biology labs. While the benefit of courses with research experience is widely accepted, it can be challenging to measure conceptual research skills in a quick and easily scalable manner. We developed a card-sorting task to differentiate between novice and expert conceptualization of research principles. There were significant differences in the way faculty/postdocs, graduate students, and undergraduate students organized their information, with faculty/postdocs more likely to use deep feature sorting patterns related to research approach. When provided scaffolding of group names reflecting expert-like organization, participant groups were better able to sort by that organization, but undergraduate students did not reach expert levels. Undergraduates with Advanced Placement experience were more likely to display expert-like thinking than undergraduates without Advanced Placement Biology experience and non-PEER (persons excluded because of their Ethnicity or Race) students displayed more expert-like thinking than PEER students. We found evidence of undergraduates in various stages of development toward expert-like thinking in written responses. This card-sorting task can provide a framework for analyzing student's conceptualizations of research and identify areas to provide added scaffolding to help shift from novice-like to expert-like thinking.

Investigating Instructor Talk in Novel Contexts: Widespread Use, Unexpected Categories, and an Emergent Sampling Strategy.

Instructor Talk-noncontent language used by instructors in classrooms-is a recently defined and promising variable for better understanding classroom dynamics. Having previously characterized the Instructor Talk framework within the context of a single course, we present here our results surrounding the applicability of the Instructor Talk framework to noncontent language used by instructors in novel course contexts. We analyzed Instructor Talk in eight additional biology courses in their entirety and in 61 biology courses using an emergent sampling strategy. We observed widespread use of Instructor Talk with variation in the amount and category type used. The vast majority of Instructor Talk could be characterized using the originally published Instructor Talk framework, suggesting the robustness of this framework. Additionally, a new form of Instructor Talk-Negatively Phrased Instructor Talk, language that may discourage students or distract from the learning process-was detected in these novel course contexts. Finally, the emergent sampling strategy described here may allow investigation of Instructor Talk in even larger numbers of courses across institutions and disciplines. Given its widespread use, potential influence on students in learning environments, and ability to be sampled, Instructor Talk may be a key variable to consider in future research on teaching and learning in higher education.

Identification of Variants in RET and IHH Pathway Members in a Large Family With History of Hirschsprung Disease.

BACKGROUND & AIMS: Hirschsprung disease (HSCR) is an inherited congenital disorder characterized by absence of enteric ganglia in the distal part of the gut. Variants in ret proto-oncogene (RET) have been associated with up to 50% of familial and 35% of sporadic cases. We searched for variants that affect disease risk in a large, multigenerational family with history of HSCR in a linkage region previously associated with the disease (4q31.3-q32.3) and exome wide. METHODS: We performed exome sequencing analyses of a family in the Netherlands with 5 members diagnosed with HSCR and 2 members diagnosed with functional constipation. We initially focused on variants in genes located in 4q31.3-q32.3; however, we also performed an exome-wide analysis in which known HSCR or HSCR-associated gene variants predicted to be deleterious were prioritized for further analysis. Candidate genes were expressed in HEK293, COS-7, and Neuro-2a cells and analyzed by luciferase and immunoblot assays. Morpholinos were designed to target exons of candidate genes and injected into 1-cell stage zebrafish embryos. Embryos were allowed to develop and stained for enteric neurons. RESULTS: Within the linkage region, we identified 1 putative splice variant in the lipopolysaccharide responsive beige-like anchor protein gene (LRBA). Functional assays could not confirm its predicted effect on messenger RNA splicing or on expression of the mab-21 like 2 gene (MAB21L2), which is embedded in LRBA. Zebrafish that developed following injection of the lrba morpholino had a shortened body axis and subtle gut morphological defects, but no significant reduction in number of enteric neurons compared with controls. Outside the linkage region, members of 1 branch of the family carried a previously unidentified RET variant or an in-frame deletion in the glial cell line derived neurotrophic factor gene (GDNF), which encodes a ligand of RET. This deletion was located 6 base pairs before the last codon. We also found variants in the Indian hedgehog gene (IHH) and its mediator, the transcription factor GLI family zinc finger 3 (GLI3). When expressed in cells, the RET-P399L variant disrupted protein glycosylation and had altered phosphorylation following activation by GDNF. The deletion in GDNF prevented secretion of its gene product, reducing RET activation, and the IHH-Q51K variant reduced expression of the transcription factor GLI1. Injection of morpholinos that target ihh reduced the number of enteric neurons to 13% ± 1.4% of control zebrafish. CONCLUSIONS: In a study of a large family with history of HSCR, we identified variants in LRBA, RET, the gene encoding the RET ligand (GDNF), IHH, and a gene encoding a mediator of IHH signaling (GLI3). These variants altered functions of the gene products when expressed in cells and knockout of ihh reduced the number of enteric neurons in the zebrafish gut.

Collectively Improving Our Teaching: Attempting Biology Department-wide Professional Development in Scientific Teaching.

Many efforts to improve science teaching in higher education focus on a few faculty members at an institution at a time, with limited published evidence on attempts to engage faculty across entire departments. We created a long-term, department-wide collaborative professional development program, Biology Faculty Explorations in Scientific Teaching (Biology FEST). Across 3 years of Biology FEST, 89% of the department's faculty completed a weeklong scientific teaching institute, and 83% of eligible instructors participated in additional semester-long follow-up programs. A semester after institute completion, the majority of Biology FEST alumni reported adding active learning to their courses. These instructor self-reports were corroborated by audio analysis of classroom noise and surveys of students in biology courses on the frequency of active-learning techniques used in classes taught by Biology FEST alumni and nonalumni. Three years after Biology FEST launched, faculty participants overwhelmingly reported that their teaching was positively affected. Unexpectedly, most respondents also believed that they had improved relationships with departmental colleagues and felt a greater sense of belonging to the department. Overall, our results indicate that biology department-wide collaborative efforts to develop scientific teaching skills can indeed attract large numbers of faculty, spark widespread change in teaching practices, and improve departmental relations.

A systems approach to natural disaster resilience.

The frequency, social, and economic impacts of natural disasters show exponential increases in recent decades. Cities and countries around the world have begun to realize that these events are no longer "hundred year" storms, but repeat within a few years. As urbanisation continues throughout this century, more and more people and more economic activity will be concentrated in at-risk areas; especially as new arrivals in cities throughout Asia and Africa are likely to be concentrated in the highest risk districts, much as they often are in North America and Europe today. This article reviews recent growth of natural disasters and considers how a systems approach can improve approaches to mitigation and adaptation of these risks and to recovery from such events.

In vivo visualization of the development of the enteric nervous system using a Tg(-8.3bphox2b:Kaede) transgenic zebrafish.

The phox2b gene encodes a transcription factor that is expressed in the developing enteric nervous system (ENS). An enhancer element has been identified in the zebrafish phox2b locus that can drive tissue specific expression of reporter genes in enteric neuron precursor cells. We have generated a transgenic zebrafish line in which the Kaede fluorescent protein is under the control of this phox2b enhancer. This line has stable expression of the Kaede protein in enteric neuron precursor cells over three generations. To demonstrate the utility of this line we compared the migration and division rates of enteric neuron precursor cells in wild type and the zebrafish ENS mutant lessen.

Contrast-enhanced magnetic resonance angiography of the peripheral arteries: technique, tips, pitfalls and problems.

Contrast-enhanced magnetic resonance angiography is a reliable way to assess peripheral vascular disease. This article reviews the basic physics behind this technique and discusses our institution's experience with regard to the clinical role, recent advances in image acquisition and use of contrast agents. Problems that can affect image quality and interpretation are also highlighted.

Serum iron markers are inadequate for guiding iron repletion in chronic kidney disease.

BACKGROUND AND OBJECTIVES: Iron (Fe) overload may complicate parenteral Fe therapy used to enhance the efficacy of erythropoietic-stimulating agents in the treatment of anemia of chronic kidney disease. However, serum Fe markers are influenced by inflammation or malignancy and may not accurately reflect the amount of body Fe. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We studied the relationship between parenteral Fe therapy, conventional serum Fe markers, and liver iron concentration (LIC) measured using magnetic resonance R2 relaxometry (FerriScan) in 25 Fe-deficient predialysis chronic kidney disease patients before and 2 and 12 weeks after single high-dose intravenous Fe and in 15 chronic hemodialysis patients with elevated serum ferritin (>500 µg/L). RESULTS: In predialysis patients, there was strong dose dependency between the administered Fe dose and changes in LIC at weeks 2 and 12; however, no dose dependency between Fe dose and changes in ferritin or transferrin saturation (TSAT) were observed. In hemodialysis patients, LIC correlated with the cumulative Fe dose and duration of dialysis but not with current ferritin or TSAT. The cumulative Fe dose remained a significant independent predictor of LIC in a multiple regression model. Two dialysis patients who received >6 g parenteral Fe had substantially elevated LIC >130 µmol/g, which is associated with hemochromatosis. CONCLUSIONS: In Fe-deficient predialysis patients, intravenous Fe therapy is associated with increases in LIC unrelated to changes in conventional Fe markers. In hemodialysis patients, TSAT and ferritin are poor indicators of body Fe load, and some patients have LICs similar to those found in hemochromatosis.

Differentiation of MIS 9 and MIS 11 in the continental record: vegetational, faunal, aminostratigraphic and sea-level evidence from coastal sites in Essex, UK.

Multidisciplinary investigations of the vegetational, faunal and sea-level history inferred from the infills of buried channels on the coast of eastern Essex have a direct bearing on the differentiation of MIS 11 and MIS 9 in continental records. New data are presented from Cudmore Grove, an important site on Mersea Island that can be linked to the terrace sequence of the River Thames. The vegetational history has been reconstructed from a pollen sequence covering much of the interglacial represented. The temperate nature of the climate is apparent from a range of fossil groups, including plant remains, vertebrates (especially the rich herpetofauna), molluscs and beetles, which all have strong thermophilous components. The beetle data have been used to derive a Mutual Climatic Range reconstruction, suggesting that mean July temperatures were about 2 degrees C warmer than modern values for southeast England, whereas mean January temperatures may have been slightly colder. The sea-level history has been reconstructed from the molluscs, ostracods and especially the diatoms, which indicate that the marine transgression occurred considerably earlier in the interglacial cycle than at the neighbouring Hoxnian site at Clacton. There are a number of palynological similarities between the sequence at Cudmore Grove and Clacton, especially the presence of Abies and the occurrence of Azolla filiculoides megaspores. Moreover, both sites have yielded Palaeolithic archaeology, indeed the latter is the type site of the Clactonian (flake-and-core) industry. However, the sites can be differentiated on the basis of mammalian biostratigraphy, new aminostratigraphic data, as well as the differences in the sea-level history. The combined evidence suggests that the infill of the channel at Cudmore Grove accumulated during MIS 9, whereas the deposits at Clacton formed during MIS 11. The infill of a much later channel, yielding non-marine molluscs and vertebrates including Hippopotamus, appears to have formed during the Ipswichian (MIS 5e). This evidence is compared with other important sites of late Middle Pleistocene age in Britain and elsewhere on the continent and the importance of a multidisciplinary approach is stressed.