Designing green stormwater infrastructure (GSI) requires an accurate estimate of the contributing drainage area and a model for runoff generation. We examined some factors that add to the uncertainty associated with these two design steps in the urban environment. Delineated drainage areas at five GSI sites in southeastern Pennsylvania (PA) were compared for digital elevation model (DEM) resolutions (grid cell sizes) ranging from 8 to 300 cm.
View Article and Find Full Text PDFPeroxides find broad applications for disinfecting environmental pathogens particularly in the COVID-19 pandemic; however, the extensive use of chemical disinfectants can threaten human health and ecosystems. To achieve robust and sustainable disinfection with minimal adverse impacts, we developed Fe single-atom and Fe-Fe double-atom catalysts for activating peroxymonosulfate (PMS). The Fe-Fe double-atom catalyst supported on sulfur-doped graphitic carbon nitride outperformed other catalysts for oxidation, and it activated PMS likely through a nonradical route of catalyst-mediated electron transfer.
View Article and Find Full Text PDFAs urbanization increases across the globe, urban flooding is an ever-pressing concern. Urban fluvial systems are highly complex, depending on a myriad of interacting variables. Numerous hydraulic models are available for analyzing urban flooding; however, meeting the demand of high spatial extension and finer discretization and solving the physics-based numerical equations are computationally expensive.
View Article and Find Full Text PDFMyasthenia gravis (MG) is a chronic and progressive neuromuscular disease where autoantibodies target essential proteins such as the nicotinic acetylcholine receptor (nAChR) at the neuromuscular junction (NMJ) causing muscle fatigue and weakness. Autoantibodies directed against nAChRs are proposed to work by three main pathological mechanisms of receptor disruption: blocking, receptor internalization, and downregulation. Current models using experimental autoimmune animal models fail to recapitulate the disease pathology and are limited in clinical translatability due to disproportionate disease severity and high animal death rates.
View Article and Find Full Text PDFWe prepared a single-atom Fe catalyst supported on an oxygen-doped, nitrogen-rich carbon support (SAFe-OCN) for degrading a broad spectrum of contaminants of emerging concern (CECs) by activating peroxides such as peroxymonosulfate (PMS). In the SAFe-OCN/PMS system, most selected CECs were amenable to degradation and high-valent Fe species were present for oxidation. Moreover, SAFe-OCN showed excellent performance for contaminant degradation in complex water matrices and high stability in oxidation.
View Article and Find Full Text PDFAdv Ther (Weinh)
November 2020
Loss of the neuromuscular junction (NMJ) is an early and critical hallmark in all forms of ALS. The study design was to develop a functional NMJ disease model by integrating motoneurons (MNs) differentiated from multiple ALS-patients' induced pluripotent stem cells (iPSCs) and primary human muscle into a chambered system. NMJ functionality was tested by recording myotube contractions while stimulating MNs by field electrodes and a set of clinically relevant parameters were defined to characterize the NMJ function.
View Article and Find Full Text PDFSolving river engineering problems typically requires river flow characterization, including the prediction of flow depth, flow velocity, and flood extent. Hydraulic models use governing equations of the flow in motion (conservation of mass and momentum principles) to predict the flow characteristics. However, solving such equations can be substantially expensive, depending upon their spatial extension.
View Article and Find Full Text PDFQuantitative characterization of the strength of peripheral membrane protein-lipid bilayer interactions is fundamental in the understanding of many protein targeting pathways. SecA is a peripheral membrane protein that plays a central role in translocating precursor proteins across the inner membrane of . The membrane binding activity of the extreme N-terminus of SecA is critical for translocase function.
View Article and Find Full Text PDFData augmentation, a technique in which a training set is expanded with class-preserving transformations, is ubiquitous in modern machine learning pipelines. In this paper, we seek to establish a theoretical framework for understanding data augmentation. We approach this from two directions: First, we provide a general model of augmentation as a Markov process, and show that kernels appear naturally with respect to this model, even when we do not employ kernel classification.
View Article and Find Full Text PDFThe general secretory (Sec) system of Escherichia coli translocates both periplasmic and outer membrane proteins through the cytoplasmic membrane. The pathway through the membrane is provided by a highly conserved translocon, which in E. coli comprises two heterotrimeric integral membrane complexes, SecY, SecE, and SecG (SecYEG), and SecD, SecF, and YajC (SecDF/YajC).
View Article and Find Full Text PDFInteractions between short protein segments and phospholipid bilayers dictate fundamental aspects of cellular activity and have important applications in biotechnology. Yet, the lack of a suitable methodology for directly probing these interactions has hindered the mechanistic understanding. We developed a precision atomic force microscopy-based single-molecule force spectroscopy assay and probed partitioning into lipid bilayers by measuring the mechanical force experienced by a peptide.
View Article and Find Full Text PDFDuring the 1918-1919 pandemic, influenza mortality widely varied across populations and locations. Records of U.S.
View Article and Find Full Text PDFJ Phys Chem B
December 2014
Current understanding of virus life-cycle states and transitions between them is mainly built on knowledge of the protein shell structure encapsulating the genome. Little is known about the genome fate during viral transitions. Here, changes in the fluorescence rate from multilabeled transcript viral RNAs encapsulated in Brome mosaic virus capsids were examined as a function of the RNA state.
View Article and Find Full Text PDFThe ability of an antimicrobial, cationic polyethylenimine (PEI+) to induce the three known extracytoplasmic stress responses of Escherichia coli was quantified. Exposure of E. coli to PEI+ in solution revealed specific, concentration-dependent induction of the Cpx extracytoplasmic cellular stress response, ~2.
View Article and Find Full Text PDFObjective: To assess bleeding patterns with continuous use of the transvaginal contraceptive ring.
Methods: We did a prospective analysis of daily menstrual flow during a 21/7 cycle followed by 6 months of continuous use and institution of a randomized protocol to manage breakthrough bleeding/spotting. Seventy-four women completed the baseline 21/7 phase and were randomized equally into two groups during the continuous phase.
In all living cells, regulated passage across membranes of specific proteins occurs through a universally conserved secretory channel. In bacteria and chloroplasts, the energy for the mechanical work of moving polypeptides through that channel is provided by SecA, a regulated ATPase. Here, we use site-directed spin labeling and electron paramagnetic resonance spectroscopy to identify the interactive surface used by SecA for each of the diverse binding partners encountered during the dynamic cycle of export.
View Article and Find Full Text PDFObjective: This study measured the 10-year risk of reoperation for surgically treated pelvic organ prolapse and urinary incontinence (POPUI) in a community population.
Study Design: We conducted a prospective cohort analysis of 374 women who were > 20 years old and who underwent surgery for POPUI in 1995.
Results: The 10-year reoperation rate was 17% by Kaplan Meier analysis.
Background: Hyperglycaemia occurs in a substantial portion of critically ill patients in our intensive care units. Near normalization of elevated blood glucose levels with IV insulin may improve outcome. However, currently published IV insulin protocol are not ideal; most are relatively complex and often result in hypoglycaemia.
View Article and Find Full Text PDFThe general secretory, Sec, system translocates precursor polypeptides from the cytosol across the cytoplasmic membrane in Escherichia coli. SecB, a small cytosolic chaperone, captures the precursor polypeptides before they fold and delivers them to the membrane translocon through interactions with SecA. Both SecB and SecA display twofold symmetry and yet the complex between the two is stabilized by contacts that are distributed asymmetrically.
View Article and Find Full Text PDFDouble helicates are known to exhibit self-recognition characteristics determined by the coordination geometry of the metal involved as well as by the topicity of the ligands. Combining tridentate (terpyridine, T) or bidentate (bipyridine, B) subunits in a tritopic strand affords a set of ligands able to assemble by pairs to form double helicates, homo- or heterostranded, homo- or heterotopic, depending on the coordination properties of the metals involved. The four ligand strands, BBB, TTT, BBT, and TBT form constitutionally dynamic sets of double helicates with the metal ions Cu(I), Cu(II), and Zn(II); these helicates correspond to the correct coding of the BB, BT, and TT pairs for tetra-, penta-, and hexacoordinate Cu(I), Cu(II), and Zn(II) cations, respectively.
View Article and Find Full Text PDFThe role of domains in defining the equilibrium and kinetic folding properties of dihydrofolate reductase (DHFR) from Escherichia coli was probed by examining the thermodynamic and kinetic properties of a set of variants in which the chain connectivity in the discontinuous loop domain (DLD) and the adenosine-binding domain (ABD) was altered by permutation. To test the concept that chain cleavage can selectively destabilize the domain in which the N- and C-termini are resident, permutations were introduced at one position within the ABD, one within the DLD and one at a boundary between the domains. The results demonstrated that a continuous ABD is required for a stable thermal intermediate and a continuous DLD is required for a stable urea intermediate.
View Article and Find Full Text PDFExport of protein into the periplasm of Escherichia coli via the general secretory system is achieved by action of a ternary complex comprising the polypeptide ligand, the chaperone SecB and SecA, a peripheral component of the membrane translocon, which is itself an ATPase. The unfolded ligand is captured initially by SecB and must be transferred to SecA and subsequently through the membrane translocon into the periplasm. We have taken the first steps in the elucidation of the mechanism of this dynamic transfer by determining the interface of interaction between SecB and SecA.
View Article and Find Full Text PDFAlzheimer Dis Assoc Disord
September 2005
We compared demographics of subjects diagnosed with frontotemporal degeneration (FTD) at a group of 5 clinics specializing in this non-Alzheimer dementia against those subjects diagnosed at standard Alzheimer disease centers, to determine any differences in referral patterns between such clinics. Of the two major phenotypes of FTD, behavior and language, the latter more frequently presented to the specialty clinics (46% of FTD diagnoses versus 19%, P < 0.001).
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