1,501 research outputs found
Assessment of ns-LA-MC-ICP-MS for Pb and Sr isotopic analysis of archaeological glass : mass bias correction strategies and Corning glass standards
Microstructure of chemically modified wood using X-ray computed tomography in relation to wetting properties
X-ray computed tomography (XCT) was utilized to visualize and quantify the 2D and 3D microstructure of acetylated southern yellow pine (pine) and maple, as well as furfurylated pine samples. The total porosity and the porosity of different cell types, as well as cell wall thickness and maximum opening of tracheid lumens were evaluated. The wetting properties (swelling and capillary uptake) were related to these microstructural characteristics. The data show significant changes in the wood structure for furfurylated pine sapwood samples, including a change in tracheid shape and filling of tracheids by furan polymer. In contrast, no such changes were noted for the acetylated pine samples at the high resolution of 0.8 mu m. The XCT images obtained for the furfurylated maple samples demonstrated that all ray cells and some vessel elements were filled with furan polymer while the fibers largely remained unchanged. Furfurylation significantly decreased the total porosity of both the maple and pine samples. Furthermore, this was observed in both earlywood (EW) and latewood (LW) regions in the pine samples. In contrast, the total porosity of pine samples was hardly affected by acetylation. These findings are in line with wetting results demonstrating that furfurylation reduces both swelling and capillary uptake in contrast to acetylation which reduces mostly swelling. Furfurylation significantly increased the cell wall thickness of both the maple and pine samples, especially at higher levels of furfurylation
Maintaining the Integrity of FBA-Based Interventions in Schools
The best interventions and best laid plans are brought into jeopardy when they are implemented inappropriately or of insufficient duration. Six factors that affect fidelity of treatment in relationship to functional behavioral assessment (FBA) are discussed: a) understanding the function of and the contextual valuables that support target behavior, b) adult knowledge of effective interventions, c) adult acceptance of the intervention, d) selection of suitable replacement behavior, e) selection of the standard to judge behavior change, and f) utilization of procedures to enhance integrity of implementation. Examples and suggestions for improving treatment fidelity in schools are offered
K 3-22: a D-type symbiotic star
A goal of the IPHAS survey is to determine the frequency and nature of
emission-line sources in the Galactic plane. According to our selection
criteria, K 3-22 is a candidate symbiotic star, but it was previously
classified as a planetary nebula. To determine its nature, we acquired a
low-resolution optical spectrum of K 3-22. Our analysis of our spectroscopy
demonstrates that K 3-22 is indeed a D-type symbiotic star, because of its high
excitation nebular spectrum and the simultaneous presence of Raman-scattered O
VI emission at 6825 and 7082 angstrom, which is detected primarily in symbiotic
stars.Comment: 3 pages, 1 figure. Accepted for publication on Astronomy and
Astrophysic
Integrating Academic and Non-Academic Instruction for Students with Emotional/Behavioral Disorders
Students with emotional/behavioral disorders exhibit a wide range of academic and behavioral problems. Not surprisingly, there is growing support for integrating instruction to address overlapping students\u27 needs in both areas. In this article, we discuss instructional variables that contribute to a positive classroom climate and that serve as setting events for more focused group-individual instructional programs. We draw on the accumulated research to identify common non-academic challenges that should be incorporated into those programs. We examine issues that relate to the efficacy of instruction and also the cultural and chronological age differences among students and how they relate to planning for instruction. Finally, we offer several forms that illustrate ways to combine academics and non-academics into a manageable instructional plan
Muscle Synergies Obtained from Comprehensive Mapping of the Cortical Forelimb Representation Using Stimulus Triggered Averaging of EMG Activity
This work is licensed under a Creative Commons Attribution 4.0 International License.Neuromuscular control of voluntary movement may be simplified using muscle synergies similar to those found using non-negative matrix factorization. We recently identified synergies in electromyography (EMG) recordings associated with both voluntary movement and movement evoked by high-frequency long-duration intracortical microstimulation applied to the forelimb representation of the primary motor cortex (M1). The goal of this study was to use stimulus-triggered averaging (StTA) of EMG activity to investigate the synergy profiles and weighting coefficients associated with poststimulus facilitation, as synergies may be hard-wired into elemental cortical output modules and revealed by StTA. We applied StTA at low (LOW, ∼15 μA) and high intensities (HIGH, ∼110 μA) to 247 cortical locations of the M1 forelimb region in two male rhesus macaques while recording the EMG of 24 forelimb muscles. Our results show that 10–11 synergies accounted for 90% of the variation in poststimulus EMG facilitation peaks from the LOW-intensity StTA dataset while only 4–5 synergies were needed for the HIGH-intensity dataset. Synergies were similar across monkeys and current intensities. Most synergy profiles strongly activated only one or two muscles; all joints were represented and most, but not all, joint directions of motion were represented. Cortical maps of the synergy weighting coefficients suggest only a weak organization. StTA of M1 resulted in highly diverse muscle activations, suggestive of the limiting condition of requiring a synergy for each muscle to account for the patterns observed
Marine biogenics in sea spray aerosols interact with the mTOR signaling pathway
Sea spray aerosols (SSAs) have profound effects on our climate and ecosystems. They also contain microbiota and biogenic molecules which could affect human health. Yet the exposure and effects of SSAs on human health remain poorly studied. Here, we exposed human lung cancer cells to extracts of a natural sea spray aerosol collected at the seashore in Belgium, a laboratory-generated SSA, the marine algal toxin homoyessotoxin and a chemical inhibitor of the mammalian target of rapamycin (mTOR) pathway. We observed significant increased expression of genes related to the mTOR pathway and Proprotein convertase subtilisin/kexin type 9 (PCSK9) after exposure to homoyessotoxin and the laboratory-generated SSA. In contrast, we observed a significant decrease in gene expression in the mTOR pathway and of PCSK9 after exposure to the natural SSA and the mTOR inhibitor, suggesting induction of apoptosis. Our results indicate that marine biogenics in SSAs interact with PCSK9 and the mTOR pathway and can be used in new potential pharmaceutical applications. Overall, our results provide a substantial molecular evidence base for potential beneficial health effects at environmentally relevant concentrations of natural SSAs
Putting Quality Functional Assessment into Practice in Schools: A Research Agenda on Behalf of E/BD Students
The discipline provisions of the IDEA place emphasis on gaining an understanding of why the student is motivated to engage in problem behavior and to consider, when appropriate, positive behavioral interventions, strategies, and supports to address the behavior. These legislative mandates bring center stage a range of new duties and responsibilities for the IEP team. This article discusses the problems that school divisions across the country are encountering when implementing these requirements and recommends a course of research to address these issues
Sea spray aerosols, a new wind in coastal monitoring
A growing number of epidemiological studies are confirming what appears to be common knowledge around the world: i.e. that human health benefits can often be linked directly to the proximity of oceans and seas. People living near the coast are generally healthier, and have longer life-expectancies than urban dwellers. These health benefits are attributed to the quality of air and food, the physical and psychiological advantages provided by the wide range of (cheap) recreational possibilities, and the constant exposure to immunological cues that boost the overall function of the human immune system. Little is known, though, about the relative importance of each of these factors. The inhalation of aerosolized triggers, which gained attention due to emerging harmful algal blooms that cause respiratory distress, probably varies strongly on spatiotemporal scales. Yet, to date, only a handful of studies have characterized the composition of seaspray aerosols (SSAs), and none have done so on a regular basis. Here, we present a new methodology that was used to monitor the composition of SSAs along the Belgian coast during summer. Overall, these efforts aim to enhance our understanding of the natural variability of immunological cues present in SSAs and, hence, their contribution to the health benefits that are associated with blue environments
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