Mangrove or mudflat: Prioritising fish habitat for conservation in a turbid tropical estuary

Mangrove habitats are typically the focus of conservation efforts in tropical estuaries because their structural complexity is thought to support greater biodiversity and nursery function than unvegetated habitats. However, evidence for this paradigm has been equivocal in turbid tropical estuaries where unvegetated mudflats are also highly productive. The present study compared the community composition, biodiversity, nursery-role and commercial fish biomass in two mangrove habitats and one mudflat habitat in the Gulf of Paria, Trinidad. A total of 12 705 fishes, comprising 63 species from 26 families, were sampled in mangrove creeks, seaward mangrove fringe and the subtidal margin of an intertidal mudflat from June 2014 to June 2015. The composition of the creek and mudflat communities were distinct, while the community of the mangrove fringe more closely resembled the mudflat than the mangrove creeks. Mean species richness (MSR), total species richness (TSR) extrapolated from species accumulation curves, and juvenile species richness (JSR) were significantly greater in the mudflat (MSR = 11.4 ± 1.0; TSR = 75 ± 14; JSR = 9.1 ± 0.8) than mangrove creeks (MSR = 9.0 ± 0.5; TSR = 49 ± 3; JSR = 6.1 ± 0.4) and the seaward mangrove fringe (MSR = 6.4 ± 0.7; TSR = 58 ± 14; JSR = 5.2 ± 0.4). Meanwhile, Shannon Weiner diversity, juvenile fish abundance and commercial fish biomass were comparable between habitats. These findings caution against the generalisation that mangroves are the most important habitat for fishes in turbid tropical estuaries. There is now a growing body of evidence that mudflats warrant consideration as important repositories of biodiversity and nursery function for juvenile fishes

10 um wavefront spatial filtering: first results with chalcogenide fibers

Wavefront cleaning by single-mode fibers has proved to be efficient in optical-infrared interferometry to improve calibration quality. For instance, the FLUOR instrument has demonstrated the capability of fluoride glass single-mode fibers in this respect in the K and L bands. New interferometric instruments developped for the mid-infrared require the same capability for the 8-12 um range. We have initiated a program to develop single-mode fibers in the prospect of the VLTI mid-infrared instrument MIDI and of the ESA/DARWIN and NASA/TPF missions that require excellent wavefront quality. In order to characterize the performances of chalcogenide fibers we are developping, we have set up an experiment to measure the far-field pattern radiated at 10 um. In this paper, we report the first and promising results obtained with this new component.Comment: Conference "Interferometry for Optical Astronomy II", SPIE 200

Diffuse retro-reflective imaging for improved mosquito tracking around human baited bednets

Robust imaging techniques for tracking insects have been essential tools in numerous laboratory and field studies on pests, beneficial insects and model systems. Recent innovations in optical imaging systems and associated signal processing have enabled detailed characterisation of nocturnal mosquito behaviour around bednets and improvements in bednet design, a global essential for protecting populations against malaria. Nonetheless, there remain challenges around ease of use for large scale in situ recordings and extracting data reliably in the critical areas of the bednet where the optical signal is attenuated. Here we introduce a retro-reflective screen at the back of the measurement volume, which can simultaneously provide diffuse illumination, and remove optical alignment issues whilst requiring only one-sided access to the measurement space. The illumination becomes significantly more uniform, although, noise removal algorithms are needed to reduce the effects of shot noise particularly across low intensity bednet regions. By systematically introducing mosquitoes in front and behind the bednet in lab experiments we are able to demonstrate robust tracking in these challenging areas. Overall, the retro-reflective imaging setup delivers mosquito segmentation rates in excess of 90% compared to less than 70% with back-lit systems

Benthic Microalgal Production at Stellwagen Bank, Massachusetts Bay, USA

Benthic microalgal chlorophyll a and production were measured at 3 sites at Stellwagen Bank, a cold temperate continental shelf habitat in Massachusetts Bay, USA, during August 1991. Benthic microalgal chlorophyll a averaged 39.8 Mg M-2, vs average integrated phytoplankton chlorophyll a of 25.9 mg m-2. Gross benthic microalgal production, measured by oxygen exchange in clear and opaque benthic chambers, averaged 20.9 mg C m-2 h-1. This production was supported by average daily light fluxes to the bottom that never exceeded 1 % of surface incident radiation and were as low as 4.7 μE M-2 s-1. These results indicate that benthic microalgal production can be spatially extensive and quantitatively important in continental shelf ecosystems

Quantifying late-stage host-seeking behaviour of Anopheles gambiae at the insecticidal net interface using a baited-box bioassay

Background Insecticide-treated nets (ITNs) are losing efficacy against pyrethroid-resistant malaria vector populations throughout Africa. Safeguarding bed net efficacy, vital for effective malaria control, requires greater knowledge of mosquito–ITN interactions and how this impacts on the mosquito. Methods A purpose-built benchtop apparatus with a closed 10 cm cubic chamber (the ‘Baited-box’) was used to video record behaviour of individual free-flying female Anopheles gambiae during approach and blood-feeding on a human hand through untreated nets and ITNs at close range. Time and duration of defined behavioural events, and knockdown and mortality at 1- and 24-h post-exposure respectively, were recorded for pyrethroid susceptible and resistant mosquitoes. Results Using three human volunteers differing in relative attractiveness to mosquitoes, 328 mosquitoes were individually tested. There were no significant differences between response rates to ITNs and untreated nets (P > 0.1) or between resistant (Tiassalé) and susceptible (Kisumu) mosquito strains, at untreated nets (P = 0.39) or PermaNet 2.0 (P = 1). The sequence of behavioural events from host-seeking to completion of blood-feeding was consistent in all tests but duration and start time of events involving net contact were reduced or delayed respectively with ITNs. Blood-feeding durations at untreated nets (means from 4.25 to 8.47 min (95% confidence interval (CI) = 3.39–9.89) at 3 human volunteers) were reduced by 37–50% at PermaNet 2.0, in susceptible (mean 2.59–4.72 min, 95% CI = 1.54–5.5, P =  0.2), and neither ITN type showed detectable spatial repellency. After initial contact, blood-feeding commenced later at Olyset (mean 2.76 min, 95% CI = 1.74–3.76, P = 0.0009) and PermaNet (mean 2.4 min, 95% CI = 1.52–3.33, P = 0.0058) than untreated netting (mean 0.68 min, 95% CI = 0.42–0.94). Conclusions The baited box offers a simple method for detailed characterization of mosquito behavioural responses to insecticidal nets, for comparing entomological modes of action between nets and for defining the behavioural responses of particular mosquito strains or populations. The device has potential as a screening assay in the search for novel net treatments and for investigations into behavioural resistance mechanisms

Detecting bipolar depression from geographic location data

Objective: This work aims to identify periods of depression using geolocation movements recorded from mobile phones in a prospective community study of individuals with bipolar disorder (BD). Methods: Anonymised geographic location recordings from 22 BD participants and 14 healthy controls (HC) were collected over 3 months. Participants reported their depressive symptomatology using a weekly questionnaire (QIDS-SR16). Recorded location data were pre-processed by detecting and removing imprecise data points and features were extracted to assess the level and regularity of geographic movements of the participant. A subset of features were selected using a wrapper feature selection method and presented to (a) a linear regression model and a quadratic generalised linear model with a logistic link function for questionnaire score estimation; and (b) a quadratic discriminant analysis classifier for depression detection in BD participants based on their questionnaire responses. Results: HC participants did not report depressive symptoms and their features showed similar distributions to nondepressed BD participants. Questionnaire score estimation using geolocation-derived features from BD participants demonstrated an optimal mean absolute error rate of 3.73 while depression detection demonstrated an optimal (median±IQR) F1 score of 0.857±0.022 using 5 features (classification accuracy: 0.849±0.016; sensitivity: 0.839±0.014; specificity: 0.872±0.047). Conclusion: These results demonstrate a strong link between geographic movements and depression in bipolar disorder. Significance: To our knowledge this is the first community study of passively recorded objective markers of depression in bipolar disorder of this scale. The techniques could help individuals monitor their depression and enable healthcare providers to detect those in need of care or treatment

Verbal learning impairment in euthymic bipolar disorder: BDI v BDII

AbstractObjectivesCognitive impairment is known to occur in bipolar disorder (BD), even in euthymic patients, with largest effect sizes often seen in Verbal Learning and Memory Tasks (VLT). However, comparisons between BD Type-I and Type-II have produced inconsistent results partly due to low sample sizes.MethodsThis study compared the performance of 183 BDI with 96 BDII out-patients on an adapted version of the Rey Verbal Learning Task. Gender, age, years of education, mood scores and age at onset were all used as covariates. Current medication and a variety of illness variables were also investigated for potential effects on VLT performance.ResultsBDI patients were significantly impaired relative to BDII patients on all five VLT outcome measures after controlling for the other variables [Effect Sizes=.13–.17]. The impairments seem to be unrelated to drug treatment and largely unrelated to illness variables, although age of onset affected performance on three outcome measures and number of episodes of mood elevation affected performance on one.LimitationsThis study used historical healthy controls. Analysis of potential drug effects was limited by insufficient participants not being drug free. Cross-sectional nature of the study limited the analysis of the potential effect of illness variables.ConclusionsThis study replicates earlier findings of increased verbal learning impairment in BDI patients relative to BDII in a substantially larger sample. Such performance cannot be wholly explained by medication effects or illness variables. Thus, the cognitive impairment is likely to reflect a phenotypic difference between bipolar sub-types

Greater than the Sum of its Parts: Centering Science within Elementary STEM Education

Conceptualizing STEM Integration For our reform efforts, the fundamental question to consider was, “What is STEM learning, or what should count as STEM learning?” The different models and definitions for Integrated STEM education range from STEM disciplines traditionally taught as separate and distinct content areas to integration among the four STEM disciplines (NAE and NRC, 2014; Stohlmann et al., 2012). Teacher educators are often challenged to design STEM learning experiences within teacher preparation courses that prepare for the reality of classrooms while presenting pedagogical alternatives (Corp et al., 2020). Many researchers, for instance, Roehrig et al. (2012) distinguish between content and context integration of STEM. Content integration requires the blending of knowledge from different content fields into a single curricular activity or unit to build a collective knowledge of STEM from multiple content areas (Roehrig et al., 2012; Wang et al., 2011) while context integration, “primarily focuses on the content of one discipline and uses contexts from others” to make the content more relevant (Roehrig et al., 2012, p. 9). Most researchers conclude that STEM integration should involve the merging of some or all the STEM disciplines to solve real-world problems (Moore et al., 2020; Rinke et al., 2016). Our conceptualization of STEM integration stems from (1) Dewey’s work (1938) that highlights learning as an active process that involves students engaged in experiences situated in and connected to the real world and, (2) ideas based on social constructivism developed by Vygotsky (1978) that emphasize learning via social interactions among individuals within a social setting. Constructionist theory (Ackermann, 2001; Harel and Papert, 1991; Papert, 1980) also framed learning experiences in the integrated STEM semester. Teaching Integrated STEM calls for pedagogies that pro-mote active learning that engages students in social interactions while working collaboratively in teams (Moore et al., 2014), and knowledge that is constructed via social discourse (Stohlmann et al., 2012). Other pedagogies that are fundamental to conceptualizing STEM learning are inquiry-based and hands-on strategies promoted in the Next Generation Science Standards (Bybee, 2009); NGSS Lead States, 2013), problem-based learning that involves a problem to solve (Shaughnessy, 2013) and connections to real-life experiences (Kelley and Knowles, 2016). In leading our curriculum reform effort, we draw upon the viewpoint that STEM curriculum must involve both content and context integration. Our framework positions science at the center placing emphasis on scientific inquiry (Kelley and Knowles, 2016). Integrated STEM education has strong ties to inquiry processes allowing students to formulate questions, participate in investigations that facilitate engineering design, and integrate technology and mathematics to design solutions to complex real-world problems (Kennedy and Odell, 2014; Moore and Smith, 2014). The framework served as a guide to inform our Integrated STEM curriculum design and STEM pathways (shared assignments) across multiple courses within the STEM Semester as explained in the subsequent sections