1,349 research outputs found
Developing New Methods to Quantify Stress in Wildlife Using Liquid Chromatography Tandem Mass Spectrometry
Stress levels in wildlife species are an accurate indicator of an animal’s well-being and can reflect decreases in habitat quality. Stress levels can be measured by the presence of the stress response hormones cortisol, cortisone, and corticosterone. Analysis of these stress hormones in fecal samples has been widely used because feces can be easily obtained and non-invasively collected in the field. Methods of detecting stress levels from fecal samples of wildlife species are currently limited to enzyme immunoassay testing. This method uses antibodies to bind to target stress hormones. However, immunoassay testing can be time consuming and very expensive2. We propose that Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) offers a new method to quantify levels of the stress hormones from fecal samples that is less expensive and time consuming than traditional immunoassays1. As part of the Idaho Science Talent Expansion Program (STEP), we are developing a simple, accurate, and relatively inexpensive method to detect stress hormones in fecal samples from free-ranging pygmy rabbits (Brachylagus idahoensis) and sage grouse (Centrocercus urophasianus) using LC-MS/MS
Real-time Automatic M-mode Echocardiography Measurement with Panel Attention from Local-to-Global Pixels
Motion mode (M-mode) recording is an essential part of echocardiography to
measure cardiac dimension and function. However, the current diagnosis cannot
build an automatic scheme, as there are three fundamental obstructs: Firstly,
there is no open dataset available to build the automation for ensuring
constant results and bridging M-mode echocardiography with real-time instance
segmentation (RIS); Secondly, the examination is involving the time-consuming
manual labelling upon M-mode echocardiograms; Thirdly, as objects in
echocardiograms occupy a significant portion of pixels, the limited receptive
field in existing backbones (e.g., ResNet) composed from multiple convolution
layers are inefficient to cover the period of a valve movement. Existing
non-local attentions (NL) compromise being unable real-time with a high
computation overhead or losing information from a simplified version of the
non-local block. Therefore, we proposed RAMEM, a real-time automatic M-mode
echocardiography measurement scheme, contributes three aspects to answer the
problems: 1) provide MEIS, a dataset of M-mode echocardiograms for instance
segmentation, to enable consistent results and support the development of an
automatic scheme; 2) propose panel attention, local-to-global efficient
attention by pixel-unshuffling, embedding with updated UPANets V2 in a RIS
scheme toward big object detection with global receptive field; 3) develop and
implement AMEM, an efficient algorithm of automatic M-mode echocardiography
measurement enabling fast and accurate automatic labelling among diagnosis. The
experimental results show that RAMEM surpasses existing RIS backbones (with
non-local attention) in PASCAL 2012 SBD and human performances in real-time
MEIS tested. The code of MEIS and dataset are available at
https://github.com/hanktseng131415go/RAME
Non-ideal optical isotropy of blue phase liquid crystal
Since 1981, blue phase liquid crystal (BPLC) was regarded as optical isotropy and high contrast ratio (CR) should be achieved easily. However, low CR of BPLC display was reported in all literatures. Here, we show BPLC is non-ideal optical isotropy which leads to poor CR. In our report, BPLC not only revealed primary structure of double-twist cylinder and secondary structure of lattice but also revealed tertiary structure of self-alignment on electrode surface. This finding will be useful to improve CR and inspire researches in display industry and academics
Quantum Field Theoretical Description of Unstable Behavior of Trapped Bose-Einstein Condensates with Complex Eigenvalues of Bogoliubov-de Gennes Equations
The Bogoliubov-de Gennes equations are used for a number of theoretical works
on the trapped Bose-Einstein condensates. These equations are known to give the
energies of the quasi-particles when all the eigenvalues are real. We consider
the case in which these equations have complex eigenvalues. We give the
complete set including those modes whose eigenvalues are complex. The quantum
fields which represent neutral atoms are expanded in terms of the complete set.
It is shown that the state space is an indefinite metric one and that the free
Hamiltonian is not diagonalizable in the conventional bosonic representation.
We introduce a criterion to select quantum states describing the metastablity
of the condensate, called the physical state conditions. In order to study the
instability, we formulate the linear response of the density against the
time-dependent external perturbation within the regime of Kubo's linear
response theory. Some states, satisfying all the physical state conditions,
give the blow-up and damping behavior of the density distributions
corresponding to the complex eigenmodes. It is qualitatively consistent with
the result of the recent analyses using the time-dependent Gross-Pitaevskii
equation.Comment: 29 page
Intravenous corticosteroid treatment in adult patients with sepsis defined by the Sepsis-3 criteria: a systematic review and meta-analysis
Objectives To summarize the effects of intravenous corticosteroid treatment for sepsis defined by the Sepsis-3 criteria in adult patients.
Design Systematic review and meta-analysis.
Methods We searched RCTs from PubMed, Embase, ClinicalTrials.gov, Cochrane Central Register of Controlled Trials, Web of Science, and International Clinical Trials Registry Platform from inception to July 12th, 2019 and updated on June 28th, 2020. Conference proceedings from relevant societies and the reference lists of previous reviews were manually screened. Abstract or full-text articles were screened by two independent investigators. We included RCTs where (1) the participants had infections and the baseline Sequential Organ Failure Assessment (SOFA) score ≥ 2 (the Sepsis-3 definitions) (2) the intervention involved any intravenous corticosteroids; (3) the control group received placebo or standard of care (4) the outcomes of interest included mortality or clinical recovery. We chose the 28-day mortality as the pre-specified primary outcome and risk ratio (RR) as the effect measure. We followed PRISMA guidelines and chose random-effects models for the pooled analyses.
Results This study included 24 RCTs and 19 of them (7,115 participants) reported the 28-day mortality. Pooled analyses showed that intravenous corticosteroid treatment compared to placebo or standard of care was not associated with a lower risk of 28-day mortality (RR, 0.88; 95%CI, 0.73 to 1.05), but with a higher risk of hyperglycemia (RR, 1.16; 95%CI, 1.06 to 1.27). Sensitivity analysis of high-quality studies revealed a similar result for the 28-day mortality (RR, 0.95; 95%CI, 0.86 to 1.05).
Conclusions Our findings suggested that intravenous corticosteroids compared to placebo or standard of care may not reduce the 28-day mortality in adult patients with sepsis defined by the Sepsis-3 criteria. Further studies are warranted to clarify the roles of disease severity and treatment timing in the effects of corticosteroid treatment in this population.
PROSPERO registration number CRD4201914308
Designing physical activity environments to accrue physical and psychological effects
Understanding how best to accrue benefits from designing physical activity and exercise programmes is needed to tackle global health problems related to physical inactivity and poor mental health. Some studies have implicated an important role for green exercise and physical activity, but there is a lack of clarity in current research. Therefore, more work is needed to understand how to design green physical activity and exercise environments that afford (invite) physical and psychological benefits to individuals. We examined whether exercising while viewing a dynamic or static image of a scene from nature would offer different affordances (invitations for behaviours to emerge), compared to the common conditions of self-selected entertainment. For this purpose, 30 participants (18 males and 12 females; age 27.5 ± 9 yrs; mass 67.6 ± 11.1 kg; stature 173.7 ± 8.2 cm) exercised in three experimental conditions in a counterbalanced design while: (i) viewing a video of a green environment, (ii) viewing a single static image of the green environment; and (iii), when using typical self-selected entertainment without viewing images of nature. A twenty-minute treadmill run was undertaken at the participants’ own self-selected speed in a laboratory while energy expenditure and psychological states (using PANAS) were assessed. Results showed no differences in energy expenditure (p > .05) or negative affect (p > .05) between conditions. However, data revealed significant differences in positive affect when participants ran with a static image and their own entertainment compared to running with a dynamic image. Results revealed how differences in affordances designed into physical activity environments can shape psychological states that emerge during exercise. Further research is needed on affordance design in physical activity and exercise by engineers, designers, planners and psychologists to explore effects of a range of simulated environments, with different target groups, such as fit and unfit individuals, elderly and children
Stabilization and pumping of giant vortices in dilute Bose-Einstein condensates
Recently, it was shown that giant vortices with arbitrarily large quantum
numbers can possibly be created in dilute Bose-Einstein condensates by
cyclically pumping vorticity into the condensate. However, multiply quantized
vortices are typically dynamically unstable in harmonically trapped nonrotated
condensates, which poses a serious challenge to the vortex pump procedure. In
this theoretical study, we investigate how the giant vortices can be stabilized
by the application of a Gaussian potential peak along the vortex core. We find
that achieving dynamical stability is feasible up to high quantum numbers. To
demonstrate the efficiency of the stabilization method, we simulate the
adiabatic creation of an unsplit 20-quantum vortex with the vortex pump.Comment: 8 pages, 6 figures; to be published in J. Low Temp. Phys., online
publication available at http://dx.doi.org/10.1007/s10909-010-0216-
Synthesis and characterization of new fluorescent two-photon absorption chromophores{
A series of dipolar and quadrupolar type two-photon absorption (TPA) compounds has been synthesized and TPA cross sections (s) were measured by Ti:sapphire femtosecond laser excitation fluorescence (l = 800 nm). Among them, the compound ) can be achieved. One quadrupolar molecule (13) possessing an arylamine donor and a pyridazine acceptor has both a high s value (1442 GM) and s/MW (1.97 GM/g)
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