Estimating pilots’ cognitive load from ocular parameters through simulation and in-flight studies

Eye tracking is the process of measuring either the point of gaze (where one is looking) or the motion of an eye relative to the head. This paper investigated use of eye gaze trackers in military aviation environment to automatically estimate pilot’s cognitive load from ocular parameters. We used a fixed base variable stability flight simulator with longitudinal tracking task and collected data from 14 military pilots. In a second study, we undertook three test flights with a BAES Hawk Trainer aircraft doing air to ground attack training missions and constant G level turn maneuvers up to +5G. Our study found that ocular parameters like rate of fixation is significantly different in different flying conditions and significantly correlate with altitude gradient during air to ground dive training task, normal load factor (G) of the aircraft during constant G level turn maneuvers and pilot’s control inceptor and tracking error in simulation tasks. Results from our studies can be used for real time estimation of pilots’ cognitive load, providing suitable warnings and alerts to the pilot in cockpit and training of military pilots on cognitive load management during operational missions

Environmental DNA of aquatic macrophytes: The potential for reconstructing past and present vegetation and environments

1. Environmental DNA is increasingly being used to reconstruct past and present biodiversity including from freshwater ecosystems. Macrophytes are especially good environmental indicators, thus their environmental DNA palaeorecord might shed light on past postglacial environments. 2. Here, we first review and compare studies that use metagenomics, targeted capture, and various barcoding and metabarcoding markers, in order to explore how each of these methods can be used to capture aquatic vegetation diversity and change. We then investigate the extent to which such a record can be leveraged for reconstructing local environmental conditions, using a case study based on macrophyte ecological niches. 3. We find that, with state-of-the-art DNA barcode reference libraries, using metabarcoding to target the P6 loop region of the chloroplast trnL (UAA) intron is optimal to maximise taxonomic resolution and the diversity of past macrophyte communities. Shotgun sequencing also retrieves a high proportion of aquatic macrophyte diversity, but has the lowest taxonomic resolution, and targeted capture needs to be more widely applied before comparisons can be made. 4. From our case study, we infer past aquatic habitats from sedimentary ancient DNA records of macrophyte taxa. We reconstructed Holocene thermal range, continentality, water pH, trophic status, and light conditions in northern Fennoscandia. We show an overall stability since 9,000 years ago, even though individual lakes display different trends and variation in local climatic and physicochemical conditions. 5. Combined with the availability of near-exhaustive barcode and traits databases, metabarcoding data can support wider ecological reconstructions that are not limited to aquatic plant taxonomic inventories but can also be used to infer past changes in water conditions and their environmental drivers. Sedimentary DNA is also a powerful tool to measure present diversity, as well as to reconstruct past lacustrine and fluvial communities of aquatic macrophytes

Anionic Fluorine and Cationic Niobium Codoped Tin Oxide Thin Films as Transparent Conducting Electrodes for Optoelectronic Applications

Exploration of alternatives for supplementing indium tin oxide electrode is currently trending due to scarcity of indium, leading to a steep increase in the cost of related optoelectronic components. Codoping of niobium (Nb) and fluorine (F) into SnO2 lattice as cationic and anionic dopants, respectively, is explored by spray deposition technique. A fixed 10 wt% F and varying Nb concentration from 0 to 5 wt% is incorporated into the SnO2 lattice. X-ray diffraction reveals substitution of Nb and F into the SnO2 lattice without altering the structure. Optical transmittance is found to increase with Nb content up to 4% of Nb (77.59%), and it decreases thereafter. Scanning electron microscope and optical profiler imply a relatively smooth surface with sharp-tipped particles which vary with Nb concentration. Sheet resistance decreases up to 3 wt% of Nb doping and increases thereafter. Contact angle measurement indicates that upon doping with Nb, the films turn hydrophilic. Among the deposited films, 4 wt% of Nb-doped film shows the highest figure of merit of 5.01 × 10−3 Ω−1. The surface work function of the 4 wt% Nb-doped SnO2 film is 4,687.85 meV. The optimal films are tested as electrodes in dye-sensitized solar cells and are discussed in detail

Holocene summer temperature reconstruction from plant sedaDNA and chironomids from the northern boreal forest

Climate-induced ecotonal shifts are expected to occur in the (sub)arctic and boreal zones in the coming decades. Understanding how these ecosystems have previously responded to climate change can provide greater insight into how ecosystems may develop under existing and future pressures. Here we present a Holocene record from Lake Horntjernet, a lake on the northern edge of the boreal forest in Northern Norway. We show vegetation development and landscape dynamics typical for Northern Fennoscandia during the Holocene. A plant sedaDNA record indicates rapid vegetation development following deglaciation with early arrival of Betula trees/shrubs. Pine forest was established by c. 8500 cal yr BP, and subsequent mid- to late Holocene vegetation assemblages are relatively stable. The aquatic ecosystem community is indicative of climatic change during the early Holocene, while strong coupling with changes in the catchment vegetation affects the water quality during the mid- and late Holocene. The chironomid record indicates lake water acidification following the establishment of pine forest and heathland. Different approaches for temperature reconstruction are calculated and the results are compared to better understand ecosystem-climate relationships and ecosystem resilience to climate change. Chironomid-inferred temperatures indicate early Holocene warming and late Holocene cooling, comparable to independent regional temperature trends. However, lake acidification impedes reliable reconstruction of chironomid-inferred temperatures in the mid-Holocene, a trend recognised in other boreal chironomid records. The application of sedaDNA plant-inferred summer temperature reconstruction is inhibited by the persistence of cold and warm tolerant species within the boreal pine forest. However, a trait-based approach reconstructed temperature trends that aligned with independent regional data. Thus, here we demonstrate the value of combined molecular and fossil-based proxies for elucidating the complex response of a boreal catchment to climate change

Postglacial species arrival and diversity buildup of northern ecosystems took millennia

What drives ecosystem buildup, diversity, and stability? We assess species arrival and ecosystem changes across 16 millennia by combining regional-scale plant sedimentary ancient DNA from Fennoscandia with near-complete DNA and trait databases. We show that postglacial arrival time varies within and between plant growth forms. Further, arrival times were mainly predicted by adaptation to temperature, disturbance, and light. Major break points in ecological trait diversity were seen between 13.9 and 10.8 calibrated thousand years before the present (cal ka BP), as well as break point in functional diversity at 12.0 cal ka BP, shifting from a state of ecosystem buildup to a state where most habitat types and biotic ecosystem components were in place. Trait and functional diversity stabilized around 8 cal ka BP, after which both remained stable, although changes in climate took place and species inflow continued. Our ecosystem reconstruction indicates a millennial-scale time phase of formation to reach stable and resilient levels of diversity and functioning.publishedVersio

Sedimentary ancient DNA shows terrestrial plant richness continuously increased over the Holocene in northern Fennoscandia

The effects of climate change on species richness are debated but can be informed by the past. Here, we generated a sedimentary ancient DNA dataset covering 10 lakes and applied novel methods for data harmonization. We assessed the impact of Holocene climate changes and nutrients on terrestrial plant richness in northern Fennoscandia. We find that richness increased steeply during the rapidly warming Early Holocene. In contrast to findings from most pollen studies, we show that richness continued to increase thereafter, although the climate was stable, with richness and the regional species pool only stabilizing during the past three millennia. Furthermore, overall increases in richness were greater in catchments with higher soil nutrient availability. We suggest that richness will increase with ongoing warming, especially at localities with high nutrient availability and assuming that human activity remains low in the region, although lags of millennia may be expected.The effects of climate change on species richness are debated but can be informed by the past. Here, we generated a sedimentary ancient DNA dataset covering 10 lakes and applied novel methods for data harmonization. We assessed the impact of Holocene climate changes and nutrients on terrestrial plant richness in northern Fennoscandia. We find that richness increased steeply during the rapidly warming Early Holocene. In contrast to findings from most pollen studies, we show that richness continued to increase thereafter, although the climate was stable, with richness and the regional species pool only stabilizing during the past three millennia. Furthermore, overall increases in richness were greater in catchments with higher soil nutrient availability. We suggest that richness will increase with ongoing warming, especially at localities with high nutrient availability and assuming that human activity remains low in the region, although lags of millennia may be expected.Peer reviewe

High resolution ancient sedimentary DNA shows that alpine plant diversity is associated with human land use and climate change.

The European Alps are highly rich in species, but their future may be threatened by ongoing changes in human land use and climate. Here, we reconstructed vegetation, temperature, human impact and livestock over the past ~12,000 years from Lake Sulsseewli, based on sedimentary ancient plant and mammal DNA, pollen, spores, chironomids, and microcharcoal. We assembled a highly-complete local DNA reference library (PhyloAlps, 3923 plant taxa), and used this to obtain an exceptionally rich sedaDNA record of 366 plant taxa. Vegetation mainly responded to climate during the early Holocene, while human activity had an additional influence on vegetation from 6 ka onwards. Land-use shifted from episodic grazing during the Neolithic and Bronze Age to agropastoralism in the Middle Ages. Associated human deforestation allowed the coexistence of plant species typically found at different elevational belts, leading to levels of plant richness that characterise the current high diversity of this region. Our findings indicate a positive association between low intensity agropastoral activities and precipitation with the maintenance of the unique subalpine and alpine plant diversity of the European Alps

Absence of mutations in four genes encoding for congenital cataract and expressed in the human brain in Tunisian families with cataract and mental retardation

<p>Abstract</p> <p>Background</p> <p>To identify the genetic defect associated with autosomal recessive congenital cataract (ARCC), mental retardation (MR) and ARCC, MR and microcephaly present in most patients in four Tunisian consanguineous families.</p> <p>Methods</p> <p>We screened four genes implicated in congenital cataract by direct sequencing in two groups of patients; those affected by ARCC associated to MR and those who presented also microcephaly. Among its three genes <it>PAX6</it>, <it>PITX3 </it>and <it>HSF4 </it>are expressed in human brain and one gene <it>LIM2 </it>encodes for the protein MP20 that interact with the protein galectin-3 expressed in human brain and plays a crucial role in its development. All genes were screened by direct sequencing in two groups of patients; those affected by ARCC associated to MR and those who presented also microcephaly.</p> <p>Results</p> <p>We report no mutation in the four genes of congenital cataract and its flanking regions. Only variations that did not segregate with the studied phenotypes (ARCC associated to MR, ARCC associated with MR and microcephaly) are reported. We detected three intronic variations in <it>PAX6 </it>gene: IVS4 -274insG (intron 4), IVS12 -174G>A (intron12) in the four studied families and IVS4 -195G>A (intron 4) in two families. Two substitutions polymorphisms in <it>PITX3 </it>gene: c.439 C>T (exon 3) and c.930 C>A (exon4) in one family. One intronic variation in <it>HSF4 </it>gene: IVS7 +93C>T (intron 7) identified in one family. And three intronic substitutions in <it>LIM2 </it>gene identified in all four studied families: IVS2 -24A>G (intron 2), IVS4 +32C>T (intron 4) and c.*15A>C (3'-downstream sequence).</p> <p>Conclusion</p> <p>Although the role of the four studied genes: <it>PAX6</it>, <it>PITX3</it>, <it>HSF4 </it>and <it>LIM2 </it>in both ocular and central nervous system development, we report the absence of mutations in all studied genes in four families with phenotypes associating cataract, MR and microcephaly.</p

Prospective evaluation of the impact of sonography on the management and surgical intervention of neonates with necrotizing enterocolitis

Background/aimEstablished indications for surgery in necrotizing enterocolitis (NEC) are pneumoperitoneum and failure to improve or clinical deterioration with medical treatment alone. It has been proposed that infants with intestinal necrosis may benefit from surgery in the absence of one of these indications yet the diagnosis of definitive intestinal necrosis is challenging. Recent data suggest that abdominal ultrasound (US) examination focused on the gastrointestinal tract and the peritoneal cavity may be of utility in this regard. The aim of this study was to evaluate the ability of abdominal US to detect intestinal necrosis in infants with radiographically confirmed NEC.MethodsTwenty-six consecutive infants with Bell stage II or III NEC were prospectively included in the study between September 2013 and July 2014. Infants with a pre-existing indication for surgery were excluded. At least one abdominal US examination was performed in each patient using a standardized previously described method. Surgery was performed at the discretion of the attending surgeon based on clinical and imaging findings. Clinical, radiographic, US, and intra-operative data were recorded to allow comparison between US findings, surgical findings and outcome.ResultsUS demonstrated signs of intestinal necrosis in 5 of the 26 patients. All of these five had laparotomy. Intestinal necrosis requiring resection was confirmed in four and the other was found to have NEC but no necrosis was identified. In 21 patients US did not suggest intestinal necrosis. Of these, only one had surgery in whom NEC but no necrosis was identified. The remaining 20 responded to medical treatment for NEC and were assumed not to have had intestinal necrosis based on improvement without surgical intervention. The sensitivity, specificity, positive predictive value and negative predictive values of US for the detection of bowel necrosis were calculated as 100, 95.4, 80.0, and 100 %, respectively.ConclusionOur prospective findings suggest that abdominal US can identify those infants with NEC who may need surgery by detecting bowel necrosis (prior to the development of perforation or medical deterioration) with high sensitivity and specificity. Early surgical intervention in the clinical pathway of NEC may lead to improved outcomes