77 research outputs found
DataSheet1_Urbanization may enhance tornado potential: A single case report.DOCX
Tornadoes pose a risk of catastrophic economic loss and casualty in the United States. Modification of land use by urbanization alters the meteorological conditions that may impact tornado formation and intensification processes. Here we explored the simulated impact of Kansas City urbanization on the tornado potential of a supercell storm. In this studied case, we found that urbanization might enhance tornado potential by a) strengthening the low-level streamwise vorticity in the storm inflow region, thus forming stronger rotating updrafts; and b) intensifying near-surface horizontal vorticity near the boundary of the forward-flank cold pool which increases the ingestion, tilting, and stretching of streamwise horizontal vorticity into vertical vorticity. The former results from the stronger east-to-west pressure perturbation gradient due to the faster, stronger outflow boundary, and the latter is mainly a result of stronger cold fronts and a better alignment of storm-relative inflow with the horizontal vorticity vector. We emphasize that our conclusions only represent one possibility of how urbanization would affect tornado potential, and a more systematic examination is needed to achieve a more general conclusion.</p
Current perspectives and trends of the research on hypertensive nephropathy: a bibliometric analysis from 2000 to 2023
Hypertensive nephropathy continues to be a major cause of end-stage renal disease and poses a significant global health burden. Despite the staggering development of research in hypertensive nephropathy, scientists and clinicians can only seek out useful information through articles and reviews, it remains a hurdle for them to quickly track the trend in this field. This study uses the bibliometric method to identify the evolutionary development and recent hotspots of hypertensive nephropathy. The Web of Science Core Collection database was used to extract publications on hypertensive nephropathy from January 2000 to November 2023. CiteSpace was used to capture the patterns and trends from multi-perspectives, including countries/regions, institutions, keywords, and references. In total, 557 publications on hypertensive nephropathy were eligible for inclusion. China (n = 208, 37.34%) was the most influential contributor among all the countries. Veterans Health Administration (n = 19, 3.41%) was found to be the most productive institution. Keyword bursting till now are renal fibrosis, outcomes, and mechanisms which are predicted to be the potential frontiers and hotspots in the future. The top seven references were listed, and their burst strength was shown. A comprehensive overview of the current status and research frontiers of hypertensive nephropathy has been provided through the bibliometric perspective. Recent advancements and challenges in hypertensive nephropathy have been discussed. These findings can offer informative instructions for researchers and scholars.</p
A Protein-Based Hydrogel for <i>In Vitro</i> Expansion of Mesenchymal Stem Cells
<div><p>Hydrogels are widely used as scaffolds in tissue engineering because they can provide excellent environments for bioactive components including growth factors and cells. We reported in this study on a physical hydrogel formed by a specific protein-peptide interaction, which could be used for the three dimensional (3D) cell culture of murine mesenchymal stem cells (mMSC). The mMSC kept dividing during the 7-day culture period and the metabolic-active cell number at day 7 was 359% more than that at day 1. This kind of physical hydrogel could be converted to a homogeneous solution by firstly adding an equal volume of culture medium and then pipeting for several times. Therefore, mMSC post culture could be easily separated from cell-gel constructs. We believed that the protein-based hydrogel system in this study could be developed into a promising scaffold for <i>in vitro</i> expansion of stem cells and cell therapy. This work would be in the general interests of researchers in the fields of biomaterials and supramolecular chemistry.</p></div
Four lead isotope abundances (mean ± SD) for diet and test substance.
a<p>significant difference between diet and test substance at <i>P</i><0.05.</p
Additional file 1: of Reduce the Sensitivity of CL-20 by Improving Thermal Conductivity Through Carbon Nanomaterials
Experimental details and equations. (DOCX 20Ă‚Â kb
If the motor system is no mirror'
Largely aided by the neurological discovery of so-called “ mirror neurons,” the attention to motor activity during action observation has exploded over the last two decades. The idea that we internally “ mirror ” the actions of others has led to a new strand of implicit simulation theories of action understanding[1][2]. The basic idea of this sort of simulation theory is that we, via an automatic covert activation of our own action representations, can understand the action and possibly the goal and/or intentions of the observed agent. In this way motor “simulation” is seen as the basis for low-level “mind-reading”; i.e. for the ascription of goals and intentional mental states to others. The thought is that one, through mirroring simulations, can get beyond the observable behaviour to the hidden minds of others. I am questioning the idea of an exclusively “mirroring” role of the motor system in social perception, which is tacitly assumed in this sort of simulation theories. Is motor activity during action observation really primarily a simulation, a detailed “echo” of the others action? My point is not that we never simulate what we observe, but rather to question whether such processes are representative of the overall motor contribution to social cognition. More and more studies on the functional properties of mirror neurons and motor facilitation during perception points to a more complex role of the motor system in action perception. Recently, several proposals have been made attempting to reinterpret and critique the function of motor activity in social situations. I shall here briefly touch on a few of these and sketch parts of my own alternative “social affordance” hypothesis of the sensorimotor contribution to social perception. By way of these analyses I highlight how traditional discussions are marred by problematic theoretical assumptions. It seems to me that we need a thorough reinterpretation not just of mirror neurons and mirroring, but also of what we take motor and social cognition to be. In my view the details of the sensorimotor findings underline the need to move beyond the simplistic idea of the motor system as a unitary output system. In terms of social cognition I question the traditional focus on hidden mental states. I suggest that the motor contribution might have more to do with understanding the process of how others choose their actions, navigate the world and relate to others than with simulating specific actual actions or mental states. I conclude that low-level simulation theories, which see the motor role in social perception as passive “mirroring,” are faced with serious empirical challenges, and that the motor system serve a much more proactive and complex cognitive role in social perception and interaction than previously thought. But my claim is also that many empirical tensions have slipped out of focus due to entrenched theoretical assumptions. Narrow theoretical expectations have marked not only the interpretations but the research itself and I propose that we are in dire need of more studies of actual contextual and interactive social perception
A cartoon representation to illustrate the formation of the hydrogels.
<p>3D networks of the hydrogels are formed by the specific protein-peptide interaction. The blue, green, red and cyan represent ULD tetramer; the yellow represent TIP-1 protein; the grey thick line represent PEG-peptide; the grey balls represent hexapeptide of WRESAI which can bind with TIP-1.</p
Statistical significance of differences in <sup>208</sup>Pb/<sup>206</sup>Pb for test substance, diet, blood, urine, and feces in different dose groups (n = 6) of respiratory lead exposure.
<p>Note: Difference are significant when <i>p</i><0.05 level.</p>a, b<p>A significant difference with blood and urine, respectively.</p>c, d, e<p>A significant difference with control group, low dose group and medium dose group, respectively.</p>f, g<p>A significant difference with test substance and diet, respectively.</p
Phenyl Trimethylsilyl Sulfide-Mediated Controlled Ring-Opening Polymerization of α‑Amino Acid <i>N</i>‑Carboxyanhydrides
We describe here the first example
of trimethylsilyl sulfide (<i>S</i>-TMS) mediated controlled
ring-opening polymerization (ROP)
of α-amino acid <i>N</i>-carboxyanhydrides (NCAs).
We show that phenyl trimethylsilyl sulfide (PhS-TMS), an inexpensive
and commercially available compound, mediates rapid ROP of a broad
scope of NCA monomers, produces functional polyÂ(amino acids) (PAAs)
with controllable molecular weights (MWs), narrow polydispersity index
(PDI), and an in situ generated phenyl thioester group at the <i>C</i>-terminus (PAA-SPhs). PhS-TMS offers more rapid chain initiation
than previously reported hexamethyldisilazane (HMDS) initiator, ensuring
a living polymerization with better control. Mechanistic studies suggest
that a reactive trimethylsilyl carbamate (TMSC) was generated during
the chain initiation and continued to regulate the chain propagation
through a TMS transfer process. Considering the versatility of NCAs,
and the potential of leveraging the <i>C</i>-terminal phenyl
thioester for native chemical ligation (NCL), we believe this method
may offer a powerful platform enabling the rapid generation of functional
PAAs and their <i>C</i>-terminal conjugates for numerous
biological applications
<sup>208</sup>Pb% (mean ± SD) for biological samples in different groups (n = 6).
<p>Note: Difference are significant when <i>p<</i>0.05 level.</p>D,T<p>A significant difference with diet and test substance, respectively.</p>a,b,c,d,e,f<p>A significant difference with blood, urine, feces,kidneys, liver and lungs, respectively.</p>g,h,i<p>A significant difference with control group, low-dose group and medium-dose group, respectively.</p
- …