gebhart/patrepeval huggingface dataset:
Effect of Temperature on Local Structure in Poly(ethylene oxide)−Zinc Bromide Salt Complexes (2001)

Extended X-ray absorption fine structure (EXAFS) spectroscopy was used to characterize the (PEO)n[ZnBr2(1-x)(LiBr)x] system. Values of n and x were chosen so that the average number of nearest-neighbor bromine atoms varied from 2.25 to 3 as determined by Raman spectroscopy. This study determined that the number of nearest-neighbor oxygen atoms was 3, 1, and 0 for zinc with 2, 3, and 4 nearest-neighbor bromine atoms, respectively. Some ambiguity is present in the first case, with four nearest-neighbor oxygen atoms being almost impossible and two being possible but not likely. The mean-squared displacement of the zinc−bromine bond increased almost linearly with absolute temperature, similar to the behavior observed for other covalent or ionic bonds. Interestingly, the strength of the Zn−Br bond, as determined by the change of the mean-squared displacement with temperature, was the same for all samples independent of the degree and nature of coordination. For some samples, there was a clear rise in the mean-squared displacement (MSD) of the Zn−O linkage with temperature. For other samples, the mean-squared displacement at 20 K was extremely large; consequently, the expected increase of the MSD with an increase in temperature was barely noticeable. The MSD showed a relative minimum at a temperature corresponding roughly to the glass transition temperature for all samples where data were collected in an appropriate temperature range. To our knowledge, this study represents the first time a feature in EXAFS spectra has been found to be sensitive to the glass transition temperature. The significance of this observation in terms of local structural changes at the glass transition is discussed.
Down‐regulation of chondrocyte aggrecan and type‐II Collagen gene expression correlates with increases in static compression magnitude and duration (1999)

The goal of this study was to examine the simultaneous effects of mechanical compression of chondrocytes on mRNA expression and macromolecular synthesis of aggrecan and type-II collagen. Bovine cartilage explants were exposed to different magnitudes and durations of applied mechanical compression, and levels of aggrecan and type-IIa collagen mRNA normalized to glyceraldehyde-3-phosphate dehydrogenase were measured and quantified by Northern blot analysis. Synthesis of aggrecan and type-II collagen protein was measured by radiolabel incorporation of [35S]sulfate and [3H]proline into macromolecules. The results showed a dose-dependent decrease in mRNA levels for aggrecan and type-II collagen, with increasing compression relative to physiological cut thickness applied for 24 hours. Radiolabel incorporation into glycosaminoglycans and collagen also decreased with increasing compression in a dose-related manner similar to the changes seen in mRNA expression. The modulation of aggrecan and type-II collagen mRNA and protein synthesis were dependent on the duration of the compression. Aggrecan and type-II collagen mRNA expression increased during the initial 0.5 hours of static compression; however, 4-24 hours after compression was applied total mRNA levels had significantly decreased. The synthesis of aggrecan and collagen protein decreased more rapidly than did mRNA levels after the application of a step compression. Together, these results suggest that mechanical compression rapidly alters chondrocyte aggrecan and type-II collagen gene expression on application of load. However, our results indicate that the observed decreases in biosynthesis may not be related solely to changes in mRNA expression. The mechanisms by which mechanical forces affect different segments of the biosynthetic pathways remain to be determined.
Optimal design of experiment for the identification of throttle-to-slip dynamics in two-wheeled vehicles (2010)

The design of traction control systems for motorcycles is a very challenging research topic. Among other issues, one of the most difficult task is the control-oriented modeling phase. Black-box identification procedures are very suitable for this purpose, but the required experiments are often safety-critical and limited by some aspects, such as the length of the track. In this paper, an optimal protocol has been proposed and implemented, by adapting mixed H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> input design techniques. It will be shown that this approach allows to get a less time-consuming experiment, without decreasing the accuracy of the model.
Crystallography, Morphology, Electronic Structure, and Transport in Non-Fullerene/Non-Indacenodithienothiophene Polymer:Y6 Solar Cells (2020)

Emerging nonfullerene acceptors (NFAs) with crystalline domains enable high-performance bulk heterojunction (BHJ) solar cells. Thermal annealing is known to enhance the BHJ photoactive layer morphology and performance. However, the microscopic mechanism of annealing-induced performance enhancement is poorly understood in emerging NFAs, especially regarding competing factors. Here, optimized thermal annealing of model system <b>PBDB-TF:Y6</b> (<b>Y6</b> = 2,2'-((2<i>Z</i>,2'<i>Z</i>)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-<i>e</i>]thieno[2″,3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]-thieno[3,2-<i>b</i>]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1<i>H</i>-indene-2,1-diylidene))dimalononitrile) decreases the open circuit voltage (<i>V</i><sub>OC</sub>) but increases the short circuit current (<i>J</i><sub>SC</sub>) and fill factor (FF) such that the resulting power conversion efficiency (PCE) increases from 14 to 15% in the ambient environment. Here we systematically investigate these thermal annealing effects through in-depth characterizations of carrier mobility, film morphology, charge photogeneration, and recombination using SCLC, GIXRD, AFM, XPS, NEXAFS, R-SoXS, TEM, STEM, fs/ns TA spectroscopy, 2DES, and impedance spectroscopy. Surprisingly, thermal annealing does not alter the film crystallinity, R-SoXS characteristic size scale, relative average phase purity, or TEM-imaged phase separation but rather facilitates <b>Y6</b> migration to the BHJ film top surface, changes the <b>PBDB-TF</b>/<b>Y6</b> vertical phase separation and intermixing, and reduces the bottom surface roughness. While these morphology changes increase bimolecular recombination (BR) and lower the free charge (FC) yield, they also increase the average electron and hole mobility by at least 2-fold. Importantly, the increased μ<sub>h</sub> dominates and underlies the increased FF and PCE. Single-crystal X-ray diffraction reveals that <b>Y6</b> molecules cofacially pack via their end groups/cores, with the shortest π-π distance as close as 3.34 Å, clarifying out-of-plane π-face-on molecular orientation in the nanocrystalline BHJ domains. DFT analysis of <b>Y6</b> crystals reveals hole/electron reorganization energies of as low as 160/150 meV, large intermolecular electronic coupling integrals of 12.1-37.9 meV rationalizing the 3D electron transport, and relatively high μ<sub>e</sub> of 10<sup>-4</sup> cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup>. Taken together, this work clarifies the richness of thermal annealing effects in high-efficiency NFA solar cells and tasks for future materials design.
Single mode, polarisation independent waveguides in silicon-on-insulator (2005)

The conditions for single mode and zero birefringence for small and deeply etched SOI waveguides are presented and discussed. It is difficult to satisfy both conditions simultaneously.
Improved reversible data hiding through full employment of image pixels (2011)

A new reversible data hiding algorithm for digital images is proposed in this paper. A single key parameter is derived in the algorithm during the hiding process. This parameter must be transferred to extract data. A 3 × 3 window slides over the cover image by one pixel unit, and one bit can be embedded at each position of the window. Thus, the ideal maximum hiding capacity is equal to the number of pixels in the image. As a result, significant increases in hiding capacity and better visual quality of message-hidden images may be achieved. The proposed algorithm is verified with simulations.
ADIPOSE-DERIVED STROMAL VASCULAR FRACTION SHOWS MARKED BONE-REGENERATIVE POTENTIAL ON A XENOHYBRID BONE SCAFFOLD (2018)

Intra-articular infusions of adipose tissue-derived stem cells (ASCs) are a promising tool for bone regenerative medicine, thanks to their multilineage differentiating ability. One major limitation...
Laboratory visit in the framework of the FSP "GRIPAVI" granted by the french ministry of foreign affairs : mission in Hanoi, Vietnam, july 3-6 2008 (2008)

In the framework of the FSP GRIPAVI "Ecologie et épidémiologie de la grippe aviaire dans les pays du Sud", a visit to the National Institute of Veterinary Research in Hanoi, Vietnam was carried out with the aim to assess the laboratory organisation, traceability and competence in the field of avian influenza virus (AN) molecular diagnosis. The assessment was conducted through interviews of the head of the virology section and scientists involved in AN detection and characterisation. The protocols in use were checked and fruitful discussions on result interpretation were carried out. The general impression of the "auditor" was that the virology team appears to be well trained on the current diagnostic procedures for MV and perfectly aware of the drawbacks of the procedures. Traceability within the laboratory appeared satisfactory. Few weak-points related to the primer sets used and the result interpretation were noticed and will be reported here. However, they can be solved easily and rapidly. A set of calibrated and inactivated AIV strains were brought to NIVR for an interlaboratory proficiency test. The samples were analysed during the week after the visit and therefore were inferred later on. The results demonstrate good performances in terms of analytical sensitivity, higher than the minimum required. All together, this review demonstrated that NNR is competent for the diagnosis of AN and can therefore be one of the good quality laboratories including in the network of GRIPAVI.
ABSTRACT 26 (2014)

Background and aims: Extra Corporeal Life Support (ECLS) has evolved to a standard of care in many pediatric centers, with thousands of patients supported to date. There is a lack of studies examining long-term outcomes including health related quality of life (HRQL). Aims: We aim to assess the HRQL of children who received cardiac ECLS, and to compare them with a healthy sample, children with chronic conditions and children who had cardiac surgery and did not receive ECLS. Methods: Prospective cohort study including children < 5 years old with diagnosis of cardiac disease who received ECLS at the Stollery Children’s Hospital between 1999 and 2009. HRQL was assessed using the PedsQLTM 4.0 Generic Core Scales. Analysis was performed with t-test for independent samples and multiple linear regression. Study approved by institutional health research ethics board. Results: Ninety-eight patients received ECLS between 2000 and 2009, 50 (51%) survived and 47 children were assessed at a median age of 4 years. Children who received veno-arterial ECLS have significantly lower PedsQLTM 4.0 than healthy children (64.9 vs. 82.2; P<0.0001), children with chronic conditions (64.9 vs. 73.1; P=0.007), and children who underwent cardiac surgery and who did not receive ECLS (64.9 vs. 81.1; P<0.0001). Multiple linear regression analysis found an independent association between higher inotrope score in the first 24 hours of ECLS, longer hospital length of stay and lower PedsQLTM 4.0 scores. Conclusions: Pediatric cardiac ECLS survivors showed lower HRQL than healthy children, children with chronic conditions and those with congenital heart disease who did not receive ECLS.
Harnessing the Spatial-Temporal Attention of Diffusion Models for High-Fidelity Text-to-Image Synthesis (2023)

Diffusion-based models have achieved state-of-the-art performance on text-to-image synthesis tasks. However, one critical limitation of these models is the low fidelity of generated images with respect to the text description, such as missing objects, mismatched attributes, and mislocated objects. One key reason for such inconsistencies is the inaccurate cross-attention to text in both the spatial dimension, which controls at what pixel region an object should appear, and the temporal dimension, which controls how different levels of details are added through the denoising steps. In this paper, we propose a new text-to-image algorithm that adds explicit control over spatial-temporal cross-attention in diffusion models. We first utilize a layout predictor to predict the pixel regions for objects mentioned in the text. We then impose spatial attention control by combining the attention over the entire text description and that over the local description of the particular object in the corresponding pixel region of that object. The temporal attention control is further added by allowing the combination weights to change at each denoising step, and the combination weights are optimized to ensure high fidelity between the image and the text. Experiments show that our method generates images with higher fidelity compared to diffusion-model-based baselines without fine-tuning the diffusion model. Our code is publicly available at https://github.com/UCSB-NLP-Chang/Diffusion-SpaceTime-Attn.
The C-terminal SET domains of ALL-1 and TRITHORAX interact with the INI1 and SNR1 proteins, components of the SWI/SNF complex (1998)

The ALL-1 gene was discovered by virtue of its involvement in human acute leukemia. Its Drosophila homolog trithorax (trx) is a member of the trx-Polycomb gene family, which maintains correct spatial expression of the Antennapedia and bithorax complexes during embryogenesis. The C-terminal SET domain of ALL-1 and TRITHORAX (TRX) is a 150-aa motif, highly conserved during evolution. We performed yeast two hybrid screening of Drosophila cDNA library and detected interaction between a TRX polypeptide spanning SET and the SNR1 protein. SNR1 is a product of snr1, which is classified as a trx group gene. We found parallel interaction in yeast between the SET domain of ALL-1 and the human homolog of SNR1, INI1 (hSNF5). These results were confirmed by in vitro binding studies and by demonstrating coimmunoprecipitation of the proteins from cultured cells and/or transgenic flies. Epitope-tagged SNR1 was detected at discrete sites on larval salivary gland polytene chromosomes, and these sites colocalized with around one-half of TRX binding sites. Because SNR1 and INI1 are constituents of the SWI/SNF complex, which acts to remodel chromatin and consequently to activate transcription, the interactions we observed suggest a mechanism by which the SWI/SNF complex is recruited to ALL-1/trx targets through physical interactions between the C-terminal domains of ALL-1 and TRX and INI1/SNR1.
ENDOR studies of VO2+: probing protein-metal ion interactions in nephrocalcin. (2000)

Nephrocalcin inhibits the growth of calcium oxalate monohydrate crystals in the mammalian kidney. Isoforms A and B contain three equivalents of gamma-carboxyglutamic acid (Gla) residues implicated in Ca2+-binding and exhibit strong inhibitor properties and high Ca2+-binding affinity (Kd approximately 10(-8) M). Isoforms C and D lack these properties and exhibit low Ca2+-binding affinity (Kd approximately 10(-6) M). With VO2+ as a structural probe, electron paramagnetic resonance (EPR) studies of the Ca2+-binding sites of isoforms B and D showed that VO2+ binds competitively with a metal ion:protein stoichiometry of 4:1. EPR spectral parameters of the VO2+ ion were consistent with only equatorial oxygen-donor ligands. EPR and angle-selected electron nuclear double resonance (ENDOR) spectra showed two equatorially positioned, metal coordinating waters in isoform D while in isoform B no ligands undergoing hydrogen exchange were found. Since isoform D showed no evidence for axially coordinated water, similarly to isoform B, it is likely that the protein residues occupying the axial sites are identical in both proteins. ENDOR spectra of VO2+-complexes of isoforms B and D were compared to spectra of the VO2+-complex with alpha-ethylmalonic acid (EMA), a molecular mimic of Gla. Spectra of the VO2+-complex of EMA showed axial water located trans to the V=O bond and outer shell water hydrogen-bonded to the vanadyl oxygen, consistent with the X-ray structure of Ca(EMA)2. We, therefore, conclude that the spatial disposition of carboxylate groups of Gla residues coordinating Ca2+ in isoforms A and B must differ from that observed in the crystal structure of Ca(EMA)2.
Direct Thickeners for Carbon Dioxide (2000)

Abstract Direct thickeners for dense carbon dioxide were designed and synthesized. Each thickener contained highly CO2-soluble "CO2-philic" fluorinated groups, while "CO2-phobic" functionalities promoted viscosity-enhancing intermolecular associations. Semifluorinated trialkyltin fluorides, fluorinated telechelic ionomers, fluoroacrylate-styrene copolymers and sulfonated fluoroacrylate-styrene copolymers, were soluble to at least several weight percent in dense carbon dioxide without the use of a cosolvent. Increases in solution viscosity were measured using falling cylinder viscometry. The most promising CO2 thickener was a styrene - heptadecafluorodecylacrylate bulk-polymerized random copolymer. The optimal composition of the copolymer was about 30 mol% styrene - 70% fluoroacrylate. For example, a 29% styrene-71%fluoroacrylate copolymer increased the viscosity of liquid CO2 by a factor of 250 at a concentration of 5 wt% and a shear rate of 20 s−1 at 297K and 34 MPa. A 0.2 wt% copolymer - 99.8 wt% CO2 solution exhibited a viscosity twice that of neat CO2 at shear rates of about 3000 s−1. Greater proportions of styrene in the thickener led to decreased CO2 solubility and solution viscosity, while lower proportions of styrene resulted in greater CO2 solubility but decreased solution viscosity. Solution viscosity increased with increasing copolymer concentration, increasing pressure and decreasing shear rate.
Oscillator Flicker Phase Noise: A Tutorial (2020)

A deep understanding of how to reduce flicker phase noise (PN) in oscillators is critical in supporting ultra-low PN frequency generation for the advanced communications and other emerging high-speed applications. Unfortunately, the current literature is either full of conflicting theories and ambiguities or too complex in mathematics, hiding the physical insights. In this brief, we comprehensively review the evolution of flicker noise upconversion theories and clarify their controversial and confusing parts. Two classes of such upconversion mechanisms in voltage-biased LC-tank oscillators (nMOS-only and complementary) are specifically compared and numerically verified using a commercial simulation model of 28-nm CMOS. We identify that non-resistive terminations of both 2nd and 3rd harmonic currents contribute to oscillation waveform asymmetries that lead to the flicker noise upconversion. Further, we discuss three 1/f <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> PN reduction mechanisms: waveform shaping, narrowing of conduction angle, and gate-drain phase shift.
A template-proximal RNA paired element contributes to Saccharomyces cerevisiae telomerase activity (2003)

The ribonucleoprotein complex telomerase is critical for replenishing chromosome-end sequence during eukaryotic DNA replication. The template for the addition of telomeric repeats is provided by the RNA component of telomerase. However, in budding yeast, little is known about the structure and function of most of the remainder of the telomerase RNA. Here, we report the identification of a paired element located immediately 5' of the template region in the Saccharomyces cerevisiae telomerase RNA. Mutations disrupting or replacing the helical element showed that this structure, but not its exact nucleotide sequence, is important for telomerase function in vivo and in vitro. Biochemical characterization of a paired element mutant showed that the mutant generated longer products and incorporated noncognate nucleotides. Sequencing of in vivo synthesized telomeres from this mutant showed that DNA synthesis proceeded beyond the normal template. Thus, the S. cerevisiae element resembles a similar element found in Kluyveromyces budding yeasts with respect to a function in template boundary specification. In addition, the in vitro activity of the paired element mutant indicates that the RNA element has additional functions in enzyme processivity and in directing template usage by telomerase.
Polymer cyclization for the emergence of hierarchical nanostructures (2021)

The creation of synthetic polymer nanoobjects with well-defined hierarchical structures is important for a wide range of applications such as nanomaterial synthesis, catalysis, and therapeutics. Inspired by the programmability and precise three-dimensional architectures of biomolecules, here we demonstrate the strategy of fabricating controlled hierarchical structures through self-assembly of folded synthetic polymers. Linear poly(2-hydroxyethyl methacrylate) of different lengths are folded into cyclic polymers and their self-assembly into hierarchical structures is elucidated by various experimental techniques and molecular dynamics simulations. Based on their structural similarity, macrocyclic brush polymers with amphiphilic block side chains are synthesized, which can self-assemble into wormlike and higher-ordered structures. Our work points out the vital role of polymer folding in macromolecular self-assembly and establishes a versatile approach for constructing biomimetic hierarchical assemblies.
Generation of Direct-Detection Optical OFDM Signal for Radio-Over-Fiber Link using Frequency Doubling Scheme with Carrier Suppression (2008)

This investigation demonstrates the generation of OFDM-RoF signal using frequency doubling. Benchmarked against the OOK format, the 4-Gb/s, 16-QAM OFDM format has four times the higher spectral efficiency with a sensitivity penalty of under 2.6-dB.
Poster (2017)

With continuing advances in the development of low-power electronics, including sensors and actuators, we anticipate a rapid expansion of pervasive computing. Wearable devices, in particular, require new modes for interaction -- many have no keyboard or touchscreen. In this work, we focus on user authentication on wearable devices. For an entertainment device, such as a VR headset, it can recognize the user and load the right game profile or music playlist. For a house climate-control system, it can adjust the environment to the wearer's preference. Most compellingly, for a health-monitoring device, it can label the sensor data with the correct identity so that the data can be stored in the correct health record. (A mix-up of sensor data could lead to incorrect decisions, with harm to the patient.) Because not all devices are personal devices -- my phone, your fitness sensor -- many devices will need to automatically recognize their wearer. They may have no interface for user identification (or PIN or password for authentication). Thus, we need a simple, wearable biometric technique to identify the user -- which could be embedded in one authentication device that shares the identity with a body-area network of other devices (earlier confirmed to be on the same body). This device should be trained once, for each user that might wear it, but thenceforth be completely automatic. Although a wristband could use a physiological biometric to recognize its wearer; we seek an alternative biometric, notably, one that might work for devices mounted on the head, neck, or chest.