Synchronous fluorescence spectroscopy (SFS) is a technique that involves the simultaneous detection of fluorescence excitation and emission at a constant wavelength difference. The spectrum yields bands that are narrower and less complex than the original excitation and emission bands. The SFS bands correspond uniquely to the fluorescing molecule.
View Article and Find Full Text PDFObjective: Biomarkers of Alzheimer disease vary between groups of self-identified Black and White individuals in some studies. This study examined whether the relationships between biomarkers or between biomarkers and cognitive measures varied by racialized groups.
Methods: Cerebrospinal fluid (CSF), amyloid positron emission tomography (PET), and magnetic resonance imaging measures were harmonized across four studies of memory and aging.
IEEE Trans Biomed Eng
April 2024
Objective: Individuals with cognitive impairment (CI) exhibit different oculomotor functions and viewing behaviors. In this work we aimed to quantify the differences in these functions with CI severity, and assess general CI and specific cognitive functions related to visual exploration behaviors.
Methods: A validated passive viewing memory test with eyetracking was administered to 348 healthy controls and CI individuals.
Objective: Compared to individuals without cognitive impairment (CI), those with CI exhibit differences in both basic oculomotor functions and complex viewing behaviors. However, the characteristics of the differences and how those differences relate to various cognitive functions have not been widely explored. In this work we aimed to quantify those differences and assess general cognitive impairment and specific cognitive functions.
View Article and Find Full Text PDFNucleic acids aptamers often fail to efficiently target some proteins because of the hydrophilic character of the natural nucleotides. Here we present hydrophobic 7-phenylbutyl-7-deaadenine-modified DNA aptamers against the Heat Shock Protein 70 that were selected via PEX and magnetic bead-based SELEX. After 9 rounds of selection, the pool was sequenced and a number of candidates were identified.
View Article and Find Full Text PDFSelf-incompatibility (SI) is a genetic mechanism of hermaphroditic plants to prevent inbreeding after self-pollination. Allogamous Poaceae species exhibit a unique gametophytic SI system controlled by two multi-allelic and independent loci, S and Z. Despite intense research efforts in the last decades, the genes that determine the initial recognition mechanism are yet to be identified.
View Article and Find Full Text PDFElectronic platforms provide an opportunity to improve the informed consent (IC) process by permitting elements shown to increase research participant understanding and satisfaction, such as graphics, self-pacing, meaningful engagement, and access to additional information on demand. However, including these elements can pose operational and regulatory challenges for study teams and institutional review boards (IRBs) responsible for the ethical conduct and oversight of research. We examined the experience of two study teams at Alzheimer's Disease Research Centers who chose to move from a paper-based IC process to an electronic informed consent (eIC) process to highlight some of these complexities and explore how IRBs and study teams can navigate them.
View Article and Find Full Text PDFDifferences in expressing facial emotions are broadly observed in people with cognitive impairment. However, these differences have been difficult to objectively quantify and systematically evaluate among people with cognitive impairment across disease etiologies and severity. Therefore, a computer vision-based deep learning model for facial emotion recognition trained on 400.
View Article and Find Full Text PDFSelf-incompatibility (SI) is a genetic mechanism preventing self-pollination in ~40% of plant species. Two multiallelic loci, called and , control the gametophytic SI system of the grass family (Poaceae), which contains all major forage grasses. Loci independent from and have been reported to disrupt SI and lead to self-compatibility (SC).
View Article and Find Full Text PDFIntroduction: We and collaborators discovered that flickering lights and sound at gamma frequency (40 Hz) reduce Alzheimer's disease (AD) pathology and alter immune cells and signaling in mice. To determine the feasibility of this intervention in humans we tested the safety, tolerability, and daily adherence to extended audiovisual gamma flicker stimulation.
Methods: Ten patients with mild cognitive impairment due to underlying AD received 1-hour daily gamma flicker using audiovisual stimulation for 4 or 8 weeks at home with a delayed start design.
Background: Hyperthermic intraperitoneal chemotherapy (HIPEC) with gemcitabine, after cytoreductive surgery, may reduce the tumor progression of pancreatic cancer through the reduction of the neoplastic volume and the subpopulation of residual pancreatic cancer stem cells, improving the survival of patients with pancreatic cancer and decreasing the recurrence of the disease.
Methods: A pilot study is performed with the first ten patients in the experimental group. A randomized study (phase II-III clinical trial) that requires a population of 42 patients, with 21 patients in each group.
Background: Self-incompatibility (SI) systems prevent self-fertilization in several species of Poaceae, many of which are economically important forage, bioenergy and turf grasses. Self-incompatibility ensures cross-pollination and genetic diversity but restricts the ability to fix useful genetic variation. In most inbred crops it is possible to develop high-performing homozygous parental lines by self-pollination, which then enables the creation of F1 hybrid varieties with higher performance, a phenomenon known as heterosis.
View Article and Find Full Text PDFBackground: Self-incompatibility (SI) is a physiological mechanism that many flowering plants employ to prevent self-fertilization and maintain heterozygosity. In the grass family this is known to be controlled by a two locus (S-Z) system; however, the SI system is intrinsically leaky. Modifier genes of both the S and Z loci and a further locus, T, are known to override SI leading to self-fertilization and self-seed production.
View Article and Find Full Text PDFObjective: Alzheimer's disease (AD) is a neurodegenerative disorder that initially presents with memory loss in the presence of underlying neurofibrillary tangle and amyloid plaque pathology. Mild cognitive impairment is the initial symptomatic stage, which is an early window for detecting cognitive impairment prior to progressive decline and dementia. We recently developed the Visuospatial Memory Eye-Tracking Test (VisMET), a passive task capable of classifying cognitive impairment in AD in under five minutes.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
June 2020
Vibrational Fundamental and overtone transitions of CH around the Δυ = 1-3 in liquid Ar, Kr, Xe and N solutions have been obtained using a low temperature cryostat and a Fourier transform infrared spectrophotometer for wavenumbers between 800 and 10,000 cm. The visible CH spectra for Δυ = 6 of ethylene in cryogenic solutions of the same solvents and liquid ethane have been measured with a low temperature cell and the thermal lens technique. Spectra in solutions show great simplification of the bands with respect to gas phase absorption bands.
View Article and Find Full Text PDF: Informed consent (IC) is critical to performing ethical research. Unfortunately, the IC process and supporting IC forms are frequently burdensome and do not necessarily meet the informational needs of participants. The intersecting legal and ethical challenges of obtaining IC from individuals with memory or cognitive deficits further exacerbate existing IC shortcomings.
View Article and Find Full Text PDFThe entorhinal-hippocampal circuit is one of the earliest sites of cortical pathology in Alzheimer's disease (AD). Visuospatial memory paradigms that are mediated by the entorhinal-hippocampal circuit may offer a means to detect memory impairment during the early stages of AD. In this study, we developed a 4-min visuospatial memory paradigm called VisMET (Visuospatial Memory Eye-Tracking Task) that passively assesses memory using eye movements rather than explicit memory judgements.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
March 2019
In this paper, we describe in detail an assembled open-path optical cavity to act as a temperature sensor of air. A metal absorption cell in a temperature-regulated tube furnace is placed at the center of an optical cavity. The optical cavity consists of two mirrors, two nitrogen buffer sleeves, and the open cell.
View Article and Find Full Text PDFBackground: Epidural analgesia during labor can provide effective pain relief, but can also lead to adverse effects. The practice of moderate exercise during pregnancy is associated with an increased level of endorphins in the blood, and this could also provide pain relief during labor. Aerobic water exercises, rather than other forms of exercise, do not negatively impact articulations, reduce edema, blood pressure, and back pain, and increase diuresis.
View Article and Find Full Text PDFThe thermal lens technique is applied to vibrational overtone spectroscopy of solutions of naphthalene (CH) in liquid hexane. The C-H fifth vibrational (Δν = 6) overtone spectrum of CH is detected at room temperature for mole fractions from 0.08 to 19 × 10 using n-CH as solvent.
View Article and Find Full Text PDFSelf-incompatibility (SI) is a mechanism that many flowering plants employ to prevent fertilisation by self- and self-like pollen ensuring heterozygosity and hybrid vigour. Although a number of single locus mechanisms have been characterised in detail, no multi-locus systems have been fully elucidated. Historically, examples of the genetic analysis of multi-locus SI, to make analysis tractable, are either made on the progeny of bi-parental crosses, where the number of alleles at each locus is restricted, or on crosses prepared in such a way that only one of the SI loci segregates.
View Article and Find Full Text PDFThe solubility of ethylene (HC=CH), propyne (CH-C≡C-H), 2-methyl-2-butene (CH-CH=C(CH)), and isoprene or 2-methyl-1, 3-butadiene (HC=C(CH)-CH=CH) in liquid argon has been measured using mid-infrared and near-infrared (NIR) absorption. Spectra were recorded in the C-H infrared (IR) region. Spectra were obtained at increasing solution composition until the magnitude of the integrated absorption band reached a maximum value, indicating a saturated solution.
View Article and Find Full Text PDFThe A-band of oxygen has been measured at low resolution at temperatures between 90 K and 373 K using the phase shift cavity ring down (PS-CRD) technique. For temperatures between 90 K and 295 K, the PS-CRD technique presented here involves an optical cavity attached to a cryostat. The static cell and mirrors of the optical cavity are all inside a vacuum chamber at the same temperature of the cryostat.
View Article and Find Full Text PDFMutation breeding has a long-standing history and in some major crop species, many of the most important cultivars have their origin in germplasm generated by mutation induction. For almost two decades, methods for TILLING (Targeting Induced Local Lesions IN Genomes) have been established in model plant species such as Arabidopsis (Arabidopsis thaliana L.), enabling the functional analysis of genes.
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