gebhart/patrepeval huggingface dataset:
Building a Better Redox Flow Battery - Innovative Diagnostics to Visualise Reactant Transport (2015)

While the optimization of PEMFCs and RFBs require addressing multiple issues, both systems share an operation mechanism based on pumping a fluid (a gas or a liquid) containing chemically reactive species across the face of an electrode. As a consequence of this characteristic, a significant source of inefficiency is linked to mass transport limitations including high pressure drop or inhomogeneous reactant flow distribution across the electrode. Previously, strategies including infrared mapping, (1) magnetic resonance imaging (2) or neutron radiography (3) were employed in an attempt to investigate fluid transport phenomena (predominantly for fuel cells). However, although those studies rendered valuable results, the measuring procedures can be considered as expensive and require delicate equipment. In this contribution, a simple and low cost methodology to study the mass transport processes in RFBs is presented. This approach relies on the instantaneous electrochemiluminescence of Luminol. By simply recording the emitted light with a low cost camera, (4) concentration profiles at the surface of the electrode were obtained presenting high temporal and spatial resolutions. In addition, modifications on the electrolyte formulation and flow rate permitted identifying turbulent flow areas located at the turn of the flow field (Fig. 1) as well as leading to the design of improved components. References: (1) Wang et al. , Journal of Power Sources, 157, 181–187 ( 2006 ). (2) Tsushima et al. , Magnetic Resonance Imaging, 23, 255-258 ( 2005 ). (3) Trabold et al. , International Journal of Heat and Mass Transfer, 49, 4712–4720 ( 2006 ). (4) Lopes et al. , Journal of Power Sources, 274, 382–392 ( 2015 ). Figure 1
What is the Effective Component in Suanzaoren Decoction for Curing Insomnia? Discovery by Virtual Screening and Molecular Dynamic Simulation (2008)

The reliable structure of gamma aminobutyric acid type A (GABA-A) receptor was built based on several criteria. According to zolpidem and GABA binding conformations, the key residues that were indicated to be the determination of binding were consistent with our simulation. Investigation of the major effective constituents from suanzaoren to modulate the GABA-A was the aim of the study. Jujuboside A, which was indicated to be the effective constituent from suanzaoren, had no blood-brain barrier (BBB) penetration and was unable to bind at both binding sites due to its large volume. In addition, the glycoside groups on jujuboside A were easily to be hydrolyzed. In contrast, jujubogenin, which was hydrolyzed from jujuboside A, had the most compatible binding conformation. In addition, jujubogenin formed two HBs with the key residue beta(2)-Thr226 and beta(2)-Tyr229 at the GABA binding site. Moreover, it gained the comparably highest scoring values among suanzaoren constituents. Furthermore, the Adsorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) descriptor predicted that jujubogenin have good BBB penetration. Consequently, we suggested jujubogenin to be the effective suanzaoren constituent to mediate the GABA-A receptor.
Projected cross-laminated timber demand and lumber supply analysis (2020)

The use of cross-laminated lumber (CLT) for building construction has gained interest in the United States (US) and Canada. Although anecdotal market size claims exist, few quantitative studies have estimated the potential market size or discussed the impact of CLT on lumber supply. This paper presents a method to quantify CLT markets and lumber supplies based on data for the Northwest US. The western US was chosen for its early adoption of CLT combined with a long history of commercial timber construction. Structural designs of archetype buildings were combined with projected multifamily residential and commercial building construction to estimate the demand for CLT. These figures were reduced to account for assumptions that address market penetration and population density. In the case study for the Northwest, the total potential market is less than the existing CLT production in western North America. Thus, the demand region was expanded to include the US and Canada west of the Rocky Mountains, resulting in an estimated demand of 800,000 m3/yr by 2030. A regional lumber supply study suggests that the lumber supply will support the existing CLT industry, which utilizes approximately 2% of the selected lumber classifications, with an unknown impact on lumber cost and production.
Geometrical ray theory; rays and traveltimes in seismic systems (second-order approximations of the traveltimes) (1989)

Abstract In this paper, I establish general laws that represent global properties for the reflected and transmitted rays in seismic systems. The method used for establishing these laws is based on Hamilton's original ideas; the laws do not depend on the specific seismic system being used.The reflected and transmitted rays, as well as their traveltimes, are described by the same four 2 X 2 matrices. These matrices are interrelated by three equations that provide the basis for the general laws and also provide relations between reflected and transmitted rays that eventually will be exploitable for downward continuation and migration.The traveltimes of reflected and transmitted rays are summed up in single functions, giving the traveltime for any pair of source and receiver positions in a seismic system and corresponding to Hamilton's point characteristics in optics. The traveltimes of the gathers commonly used in seismic exploration are special cases of the general point characteristics.The consequences from the derived laws are directly available as a priori knowledge before any actual ray tracing and computation of traveltimes are done in any particular seismic system. The laws are also available as a general foundation for future treatments of (1) downward continuation, (2) amplitudes of reflected and transmitted events, (3) true amplitude migration, (4) examples of nonuniqueness of seismic interpretations, (5) focus phenomena, and (6) higher order approximations.
Photochemistry and Cytotoxicity Evaluation of Heptamethinecyanine Near Infrared (NIR) Dyes (2013)

The present study investigates the photochemical properties of potential photosensitizers for photodynamic therapy, namely four commercial heptamethinecyanine dyes (IR125, IR780, IR813, IR820). Spectroscopic studies were made by means of laser induced fluorescence and laser flash photolysis in order to obtain fluorescence quantum yields and transient absorption spectra. Fluorescence lifetimes were also determined. The differences encountered were essentially related with the interaction of the sulfonate groups with the solvent, and also regarding the rigidification of the central bridge connecting the two nitrogen-containing heterocyclic groups. Transient absorption studies were performed both in aerated and oxygen free samples, to conclude about the formation of photoisomers and triplet state. For the four dyes under study, a cytotoxic evaluation in the dark and after irradiation was performed using HeLa cells as the model cell line, which revealed significant changes after irradiation mainly in IR125 and IR813 dyes. Confocal microscopy analysis showed that these dyes tend to enter to the intracellular space.
Analysis of efficient resource sharing among voice and data users (2002)

We present a protocol that efficiently allocates resources in a communication network among voice and data users. The proposed protocol gains efficiency over methods with separate channels for voice and data by taking advantage of idle periods in the voice activity. An exponential on-off voice activity model is used to determine the performance of distributive or centrally controlled systems. In addition, the communication systems considered can use either code division multiple access (CDMA) or time division multiple access (TDMA) as the underlying multiple access technique. In either case, the protocol is a valid mechanism for integrating voice and data in a multiple access channel. Comparisons are made between mathematical analyses using a Markov model of the servers and simulation results using a communication network simulation tool. Results for both CDMA and TDMA systems are presented.
Review on grid-forming converter control methods in high-proportion renewable energy power systems (2022)

Grid-forming (GFM) converters can provide inertia support for power grids through control technology, stabilize voltage and frequency, and improve system stability, unlike traditional grid-following (GFL) converters. Therefore, in future “double high” power systems, research on the control technology of GFM converters will become an urgent demand. In this paper, we first introduce the basic principle of GFM control and then present five currently used control strategies for GFM converters: droop control, power synchronization control (PSC), virtual synchronous machine control (VSM), direct power control (DPC), and virtual oscillator control (VOC). These five strategies can independently establish voltage phasors to provide inertia to the system. Among these, droop control is the most widely used strategy. PSC and VSM are strategies that simulate the mechanical characteristics of synchronous generators; thus, they are more accurate than droop control. DPC regulates the active power and reactive power directly, with no inner current controller, and VOC is a novel method under study using an oscillator circuit to realize synchronization. Finally, we highlight key technologies and research directions to be addressed in the future.
P2‐355: Folate deficiency impairs brain oxygen delivery in rat: Detection by non‐invasive near infrared spectroscopy (2010)

Dietary vascular risk factors, including poor folate status are powerful and potentially modifiable predictors of cognitive impairment among older adults. The prevalence of folate deficiency has been estimated at 5-10% of middle aged and elderly adults exposed to food folate fortification, and as much as 30% in unfortified populations. In mouse, we have shown consuming a diet deficient in vitamins folate, B12 and B6 to cause a 30% decrease in brain capillary density in association with significantly impaired performance on the Morris water maze. Similarly, folate deficiency in rat impairs cognition and causes cerebral microvascular damage, without concomitant neurodegeneration. Based on these observations we hypothesized that folate deficiency should result in functional decrements in cerebral blood volume, oxygen delivery and vascular reactivity, all of which should be detectable non-invasively by near-infrared spectroscopy (NIRS). We developed a NIRS device for non-invasive evaluation of these parameters in rat. We used this device to measure absolute tissue concentrations of oxygen free and bound hemoglobin, and tissue oxygen saturation, and related hemodynamic parameters at rest and during transient mild hypoxia and hypercapnia, in Sprague Dawley rats folate deficient diets for up to 20 weeks. Total hemoglobin concentration [tHb] was 23% lower in folate deficient than in control rats at baseline, hypoxia and recovery (73 ± 10 vs. 95 ± 14 μM tHb (Mean ± SD); p < 0.02). Brain tissue oxygen saturation (StO2%) was significantly lower in folate deficient than in control rats with baseline and recovery values of 55% ± 7% vs. 66% ± 4% (p < 0.03), and 43% ± 8% vs. 55% ± 6% (p < 0.01) during hypoxia for folate deficient vs. control rats respectively. However the change in brain StO2 during hypoxia was similar in both groups with a -13% ± 2% for control rats and -12% ± 4% for folate deficient rats. In contrast, arterial oxygen saturation did not differ by diet with baseline values of 96% ± 2% for both groups, indicating that the decrements detected by NIRS in brain were independent of blood oxygen carrying capacity. Our results point to microvascular rarefaction and diminished oxygen delivery as a basis of folate-deficiency associated cognitive impairment.
Low-temperature phonon, magnon and exciton effects on the polarization of BaXF4 (1978)

Studies of the polarization deviation ΔP and of the dynamic pyroelectric response (I/cρ) (dP/dT) at low temperatures of the family of barium-transition metal-fluorides BaXF4, for X = Mg, Zn, Mn, Ni and Co are reported. The various effects of acoustic and optic phonon excitation, 2D and 3D antiferromagnetic ordering in the Ni and Co salts. Frenkel excitons in the Mn salt and the subtle structural transition in the Mn salt are demonstrated.
DimethylN,N′-(1,2-phenylene)dicarbamate (2004)

The title compound, C10H12N2O4, crystallizes in the monoclinic non-centrosymmetric space group Pn with Z = 2. The two methyl carbamate groups, —N(H)—C(=O)—OCH3, are twisted away from the aromatic ring mean plane, but form a semiflexible eight-membered cavity involving the atoms of the MeO—C(=O)—N(H)—CH2—CH2—N(H)—C(=O)—OMe group. The NH groups act as hydrogen-bond donors and the C=O groups as acceptors to form intermolecular N—H⋯O hydrogen bonding with an R21(7) motif, generating extended ribbons along the b direction.
Metabolism of the aminoterminal propeptide of type III procollagen in cultures of human proximal tubular cells (1992)

Degradation of the intact form of the aminoterminal propeptide of type III procollagen (PIIINP) has been established in the liver, whereas the col 1 domain of PIIINP is extracted by the kidneys. We used native human PIIINP and col 1 domain of PIIINP to investigate the degradation of PIIINP in cultures of human proximal tubular cells. Normal renal tissue was obtained from the healthy part of kidneys surgically removed and from biopsies from a total of 10 patients. The degradation was characterized by incubation of [125I]-PIIINP followed by gel filtration. We found that in physiological concentrations (4.4 micrograms l-1 and 11.9 micrograms l-1 intact PIIINP was almost totally degraded, but not col 1 domain. High concentrations of PIIINP (20-50 micrograms l-1) had a non-linear, non-monoexponential degradation over time, which suggests several steps. Gel filtration of [125I]-PIIINP after 1 h, 3 h, 6 h and 24 h of incubation confirmed the observation by showing the rapid formation of a high-molecular-weight fraction, followed by the slower formation of a low-molecular-weight fraction. The high-molecular-weight fraction was PIIINP immunoreactive, but not the low-molecular-weight fraction. We conclude that cultures of human proximal tubular cells degrade intact human PIIINP by the formation of high- and low-molecular-weight fractions. Earlier findings that extraction of the PIIINP col 1 domain takes place in the kidneys, cannot be explained by degradation by the proximal tubular cells.
Minimizing energy consumption for handheld computers in Moby Dick (2002)

We propose a number of techniques to reduce energy consumption for mobile computers. We use extra dedicated low power modules to cut processor cycles of the main CPU, i.e., hardware and software decomposition. These modules are autonomous and can be powered down individually. Furthermore, as networking consumes a large part of a mobile system's battery resources, much effort is put into reducing energy consumption in this part. We use intelligent network interfaces with a power aware network protocol, and a MAC protocol that minimizes the 'on-time' of network interfaces to reduce energy. There is a direct link between QoS and energy consumption. Therefore we move power management into the QoS domain.
Secure file system services for web 2.0 applications (2009)

We present a design for a file system that provides a secure file storage service for Web 2.0 applications. Currently, each Web application stores its own user data. This not only burdens the applications with storing, managing, and securing user data but also deprives users from controlling their own data. With recent proposals of secure client-side cross-domain communication mechanisms, we can provide an independent file system service to Web applications. This service returns the control over user data back to the users, where users can share or restrict access to their files as they wish, and relieves web application servers from the contractual or regulatory obligation of safeguarding user data.
Suppression of Oxidative Stress as a Mechanism of Reduction of Hypercholesterolemic Atherosclerosis by Aspirin (2003)

These results suggest that aspirin, an inhibitor of cyclooxygenase, reduced the development of hypercholesterolemic atherosclerosis, and this effect was associated with a decrease in the oxidative stress.
Engineering a lifetime-based activatable probe for photoacoustic imaging (2013)

High-resolution, high-penetration depth activatable probes are needed for in-vivo imaging of enzyme activity. In this paper, we will describe the contrast mechanism of a new photoacoustic activatable probe that changes its excitation lifetime upon activation. The excitation decay of methylene blue (MB), a chromophore commonly used in therapeutic and diagnostic applications, is probed by photoacoustic lifetime contrast imaging (PLCI). The monomer of the dye presents a high-quantum yield of intersystem-crossing and long lifetime (70 μs) whereas the dimer is statically quenched with a short lifetime (a few ns). This forms the basis of a highly sensitive contrast mechanism between monomers and dimers. Two dimerization models - one using sodium sulfate, the other using sodium dodecyl sulfate - were applied to control the monomer-to-dimer ratio in MB solutions. Preliminary results show that the photoacoustic signal of a dimer solution is efficiently suppressed (&lt; 20 dB) due to their short lifetime compared to the monomer sample. Flash-photolysis of the same solutions reveals a 99% decrease in transient absorption confirming PLCI results. This contrast mechanism can be applied to design a MB dual-labeled activatable probe bound by an enzyme-specific cleavable peptide linker. When the probe is cleaved by its target, MB molecules will separate by molecular diffusion and recover their long excitation lifetime enabling their detection by PLCI. Our long-term goal is to investigate enzyme-specific imaging in small animals and establish pre-clinical data for translational research and implementation of the technology in clinical applications.
An EBNF grammar for Wiki Creole 1.0 (2007)

Today's wiki engines are not interoperable. This is an unfortunate consequence of the lack of rigorously specified standards. This technical report presents a complete and validated EBNF-based grammar for Wiki Creole, a community standard for wiki markup. Wiki Creole is also the only standard currently available. Wiki Creole is being specified using prose, leading to inconsistencies and ambiguities. Our grammar uncovered those ambiguities which we fed back into the specification process. The Wiki Creole grammar presented in this report makes the creation of Wiki Creole parsers simple using parser generators, ANTLR in our case. Using a precise specification of wiki markup lets us decouple wiki editors from wiki storage from further wiki processing tools. Based on this decoupling layer we expect innovation on these different parts to proceed independently and at a faster pace than before.
Structural behaviour of fibre reinforced sprayed concrete anchored in rock (2003)

The main objective of this investigation was to create a better foundation for design of a bolt-anchored tunnel lining. Mechanisms that influence the load bearing capacity such as compressive arch action and the irregular shape of the lining have been especially studied. A thorough investigation of the punching capacity has also been performed. It has been shown that compressive arch action has a considerable positive effect on the load bearing capacity of fibre reinforced concrete. Punching tests were performed on circular symmetrically loaded slabs that symbolised a full-scale model of sprayed concrete around a rock bolt. A thick steel ring was placed around some of the slabs in order to incorporate the effect of compressive arch action on the failure. This ring simulates to a certain degree the restraint against lateral movements that the corresponding surrounding parts in a real lining would provide on a local failure zone. All slabs that were tested without a surrounding steel ring and could freely rotate along the support failed in bending without any signs of punching. The slabs that were tested with a lateral confinement received a considerably higher load bearing capacity and a changed failure behaviour that in many cases may be regarded as pure punching. The increase of load bearing capacity due to the surrounding steel ring was caused by compressive arch action, which also transformed the failure into punching. Increasing the fibre content from 30 kg/m 3 to 60 kg/m 3 gave no observable effect on the structural response of the slabs. A comparison between existing calculation/design methods for punching and test results showed that these methods are not fully valid for a bolt-anchored tunnel lining. Finite element simulations indicated that the failure is almost inverse to the traditional mechanism of punching. The influence of the irregularity of the tunnel surface on the structural behaviour of the sprayed concrete was studied with numerical calculations using non-linear finite element analysis. A portion of a tunnel lining with a bolt placed at its centre showed that the stiffness is more affected by the irregularity than the load bearing capacity. If the bolts were consistently placed at the peaks or at the depressions in the lining, a completely different structural behaviour was observed. The load bearing capacity became considerably higher if the bolts were located at the peaks. This can be explained by the fact that the lining acted as compressed domes between the bolts and hence the high load bearing capacity.
A new macroazo-initiator for the synthesis of polymers with crown ether units (1986)

Synthese d&apos;un polyamide a partir de transdiaminodibenzo-4,4 benzo-18 crown-6, amorceur de la polymerisation radicalaire en masse du styrene a 70°C
Quantification of the Aβ peptide in Alzheimer's plaques by laser dissection microscopy combined with mass spectrometry (2005)

The accumulation and aggregation of the beta-amyloid peptide (A beta) in the brain represents a key factor in the pathogenesis of Alzheimer's disease (AD). Many of the transgenic mouse models for AD exhibit an amyloid pathology with neuritic plaques but they typically vary by the type and abundance of plaques identified in their brains and by the onset and severity of cognitive impairment. Thus, an important consideration in the characterization of AD transgenic mouse models should be the quantitative evaluation of the amyloid load in the brain together with a detailed physico-chemical analysis of A beta from the deposited plaques. Here we present an analytical procedure to collect single amyloid plaques from anatomically defined brain regions by laser dissection microscopy that can be quantitatively assessed in their A beta isoforms composition by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Quantification was achieved by stable isotope dilution using calibrated 15N-labeled A beta standards that were spiked in the sample immediately after laser dissection. Using this method, we found that the amyloid loads in brain plaques isolated from the transgenic AD mouse model PS2APP or from human were similar. Total A beta composition was estimated at approximately 50-100 fmol per excised plaque disc, as confirmed by immunoblot analysis. N-Terminal truncated A beta isoforms were identified in both transgene and human amyloid plaques but with significantly elevated levels in human samples.
Designing a wireless underwater optical communication system (2010)

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.