gebhart/patrepeval huggingface dataset:
Three‐way methods for the calibration of chromatographic systems: Comparing PARAFAC and three‐way PLS (1991)

Abstract For the calibration of chromatographic systems, different methods can be used. One class of methods utilizes three‐way approaches. The calibration problem is stated in such a way that the decomposition of a three‐way array can serve for the prediction of retention on new stationary phases. Two three‐way approaches are presented: the Unfold‐PCA and PARAFAC models. The theory of both methods is presented and the differences are highlighted, the main difference being that PARAFAC is a trilinear decomposition whereas Unfold‐PCA is not. Both three‐way methods are evaluated on a small data set consisting of retention measurements of eight solutes at six mobile phase compositions on six stationary phases. The differences in performance of the two models are minor. For calibration purposes, two variants of the methods are discussed: three‐way PLS and an extension of PARAFAC. Again the theory and differences between the two methods are explained. The predictive performance of the two methods is compared using the same data set as earlier. The differences in predictive performance, however, are minor. Both methods are capable of predicting 98% of the variation in the test sets. Yet, there are other considerations when comparing methods than predictive performance, e.g. the quality of the predictions.
Human MBP‐specific T cells regulate IL‐6 gene expression in astrocytes through cell–cell contacts and soluble factors (2001)

One of the distinctive features of multiple sclerosis (MS) attacks is homing to the CNS of activated T cells able to orchestrate humoral and cell-based events, resulting in immune-mediated injury to myelin and oligodendrocytes. Of the complex interplay occurring between T cells and CNS constituents, we have examined some aspects of T-cell interactions with astrocytes, the major components of the glial cells. Specifically, we focused on the ability of T cells to regulate the gene expression of interleukin-6 (IL-6) in astrocytes, based on previous evidence showing the involvement of this cytokine in CNS disorders. We found that T-cell adhesion and T-cell soluble factors induce IL-6 gene expression in U251 astrocytes through distinct signaling pathways, respectively, resulting in the activation of NF-kappaB and IRF-1 transcription factors. In a search for effector molecules at the astrocyte surface, we found that alpha3beta1 integrins play a role in NF-kappaB activation induced by T-cell contact, whereas interferon-gamma (IFN-gamma) receptors dominate in IRF-1 induction brought about by T-cell-derived soluble factors. Similar phenomena were observed also in normal fetal astrocyte cultures. We therefore propose that through astrocyte induction, T cells may indirectly regulate the availability of a cytokine which is crucial in modulating fate and behavior of cell populations involved in the pathogenesis of MS inflammatory lesions.
The regulation and function of ornithine decarboxylase and of the polyamines. (1979)

Publisher Summary This chapter highlights the regulation and function of ornithine decarboxylase (ODC) and of the polyamines. ODC catalyzes the synthesis of putrescine. It is necessary to distinguish among several possible functions of polyamines, to define the state of the cell at the time of induction, and to differentiate among various modes of induction of ODC activity. The chapter discusses a few new aspects of the regulation and function of ODC and of the polyamines and some of the uncertainties in the field. It also presents areas that are closely related to the regulation and the interrelationships of the polyamines in a variety of physiological and pathological states. The chapter also explores the possible functions of the polyamines.
Metathesis of Sulfur‐Containing Olefins with a Metallacyclic Aryloxo(chloro)neopentylidenetungsten Complex (1993)

Co- and self-metathesis of acyclic and unstrained sulfur-containing ligands is catalyzed by the tungsten complex 1. The catalyst is not poisoned by the sulfur-containing substituents, possibly because of the shielding of the tungsten complex and the rigidity of its coordination. The intramolecular metathesis of diallyl sulfide catalyzed by 1 provides 2,5–dihydrothiophene in 80-90% yield and ethylene.
Piezoresistive ring-shaped MEMS resonator (2009)

We have previously reported a new class of MEMS resonators based on the piezoresistive readout principle and extensional vibration mode. Those devices suffer from unwanted mode-coupling at large vibration amplitudes, giving rise to problems such as beat patterns in the time signal. In this paper, we present a novel type of piezoresistive resonator that has a shape of a ring and operates in a flexural in-plane mode shape. The new resonators can be operated at larger excitation forces without having the mode-coupling problem, as compared to the conventional piezoresistive resonators.
Structurally-redesigned concentric-tube manipulators with improved stability (2014)

Concentric-tube manipulators could experience a snapping-through motion that negatively impacts their smooth operation. This may limit their adoption in the operating room, despite their advantage of enabling dexterity within a highly confined space. In this paper, we demonstrate through the kinematics of concentric-tube robots, how this adverse effect of torsion could be reduced or potentially eliminated. As proof of principle, we demonstrate experimentally and numerically that by adopting tubular composite structures, such as multi-layer helical tubes or cellular tubes, that could be designed to exhibit higher torsional-to-bending stiffness ratio, the stability margin of concentric-tube robots can be improved up to 40%. This will allow concentric-tube robots to achieve even a higher dexterity within a more confined space.
Quantum-dot-based suspension microarray for multiplex detection of lung cancer markers: preclinical validation and comparison with the Luminex xMAP® system (2017)

A novel suspension multiplex immunoassay for the simultaneous specific detection of lung cancer markers in bronchoalveolar lavage fluid (BALF) clinical samples based on fluorescent microspheres having different size and spectrally encoded with quantum dots (QDEM) was developed. The designed suspension immunoassay was validated for the quantitative detection of three lung cancer markers in BALF samples from 42 lung cancer patients and 10 control subjects. Tumor markers were detected through simultaneous formation of specific immune complexes consisting of a capture molecule, the target antigen, and biotinylated recognition molecule on the surface of the different QDEM in a mixture. The immune complexes were visualized by fluorescently labeled streptavidin and simultaneously analyzed using a flow cytometer. Preclinical validation of the immunoassay was performed and results were compared with those obtained using an alternative 3-plex immunoassay based on Luminex xMAP<sup>®</sup> technology, developed on classical organic fluorophores. The comparison showed that the QDEM and xMAP<sup>®</sup> assays yielded almost identical results, with clear discrimination between control and clinical samples. Thus, developed QDEM technology can become a good alternative to xMAP<sup>®</sup> assays permitting analysis of multiple protein biomarkers using conventional flow cytometers.
Antisense peptide nucleic acid‐mediated knockdown of the p75 neurotrophin receptor delays motor neuron disease in mutant SOD1 transgenic mice (2003)

Re-expression of the death-signalling p75 neurotrophin receptor (p75NTR) is associated with injury and neurodegeneration in the adult nervous system. The induction of p75NTR expression in mature degenerating spinal motor neurons of humans and transgenic mice with amyotrophic lateral sclerosis (ALS) suggests a role of p75NTR in the progression of motor neuron disease (MND). In this study, we designed, synthesized and evaluated novel antisense peptide nucleic acid (PNA) constructs targeting p75NTR as a potential gene knockdown therapeutic strategy for ALS. An 11-mer antisense PNA directed at the initiation codon, but not downstream gene sequences, dose-dependently inhibited p75NTR expression and death-signalling by nerve growth factor (NGF) in Schwann cell cultures. Antisense phosphorothioate oligonucleotide (PS-ODN) sequences used for comparison failed to confer such inhibitory activity. Systemic intraperitoneal administration of this antisense PNA to mutant superoxide dismutase 1 (SOD1G93A) transgenic mice significantly delayed locomotor impairment and mortality compared with mice injected with nonsense or scrambled PNA sequences. Reductions in p75NTR expression and subsequent caspase-3 activation in spinal cords were consistent with increased survival in antisense PNA-treated mice. The uptake of fluorescent-labelled antisense PNA in the nervous system of transgenic mice was also confirmed. This study suggests that p75NTR may be a promising antisense target in the treatment of ALS.
Cooperative diversity for wireless ad hoc networks (2006)

Cooperative diversity is a novel technique proposed for conveying information in wireless ad hoc networks, where closely located single-antenna network nodes cooperatively transmit and/or receive by forming virtual antenna arrays. For its building blocks, the relay channel and the two-transmitter, two-receiver cooperative channel, we survey the latest advances made in determining the theoretical capacity bounds and describe the best practical code designs reported so far. Both theory and practice predict that cooperative communication can provide increased capacity and power savings in ad hoc networks.
Quantitative Detection of <i>Clostridium perfringens</i> in the Broiler Fowl Gastrointestinal Tract by Real-Time PCR (2005)

Strains of Clostridium perfringens are a frequent cause of food-borne disease and gas gangrene and are also associated with necrotic enteritis in chickens. To detect and quantify the levels of C. perfringens in the chicken gastrointestinal tract, a quantitative real-time PCR assay utilizing a fluorogenic, hydrolysis-type probe was developed and utilized to assay material retrieved from the broiler chicken cecum and ileum. Primers and probe were selected following an alignment of 16S rDNA sequences from members of cluster I of the genus Clostridium, and proved to be specific for C. perfringens. The assay could detect approximately 50 fg of C. perfringens genomic DNA and approximately 20 cells in pure culture. Measurements of the analytical sensitivity determined with spiked intestinal contents indicated that the consistent limit of detection with ileal samples was approximately 10(2) CFU/g of ileal material, but only about 10(4) CFU/g of cecal samples. The decreased sensitivity with the cecal samples was due to the presence of an unidentified chemical PCR inhibitor(s) in the cecal DNA purifications. The assay was utilized to rapidly detect and quantify C. perfringens levels in the gut tract of broiler chickens reared without supplementary growth-promoting antibiotics that manifested symptoms of necrotic enteritis. The results illustrated that quantitative real-time PCR correlates well with quantification via standard plate counts in samples taken from the ileal region of the gastrointestinal tract.
Cytokine Changes and Tryptophan Metabolites in Medication-Naïve and Medication-Free Schizophrenic Patients (2009)

Cytokine imbalances especially between T helper type (Th) 1 and Th2 and tryptophan breakdown were reported to be involved in the pathophysiology of schizophrenia. The hyperactive inflammatory response system could induce enhanced tryptophan breakdown. This study aimed to investigate the relationship between cytokine changes, tryptophan breakdown parameter changes and clinical parameters in patients with schizophrenia in comparison with normal controls. In the plasma of schizophrenic patients, Th1-specific interferon-gamma was significantly higher (F = 7.485, p = 0.007) and Th2-specific interleukin (IL)-4 was significantly lower (F = 126.327, p < 0.0001). The Th1-related cytokine IL-2 was lower (F = 5.409, p = 0.021) but tumor necrosis factor-alpha (TNF-alpha) and Th2-related IL-6 were higher (F = 95.004, p < 0.0001 and F = 408.176, p < 0.0001, respectively) in the plasma of schizophrenic patients. After 6 weeks of treatment, IL-6 and TNF-alpha were significantly reduced (t = -3.762, p < 0.0001 and z = -2.668, p = 0.008). At the time of admission, plasma tryptophan concentrations were lower (F = 6.339, p = 0.012) in schizophrenic patients and were negatively correlated with the total positive symptoms score (r(2) = -0.343, p = 0.004). After 6 weeks of medication, both plasma tryptophan and kynurenine concentrations were increased (t = -2.937, p = 0.005 and t = -3.214, p = 0.002, respectively). The findings of this study indicate a hyperactive pro-inflammatory response inducing a change in tryptophan metabolism that might be related to the development of positive symptoms in schizophrenia.
Cost-based Multi-QoS Job Scheduling Using Divisible Load Theory in Cloud Computing (2013)

The advent of cloud computing as a new model of service provisioning in distributed systems, encourages researchers to investigate its benefits and drawbacks in executing scientific applications such as workflows. In this research, we attempt to investigate the use of a Divisible Load Theory (DLT) to design efficient strategies to minimize the overall processing time for scheduling jobs in compute cloud environments. We consider homogeneous processors in our analysis and we derive a closed-form solution for the load fractions to be assigned to each processors. Our analysis also attempts to schedule the jobs such a way that cloud provider can gain maximum benefit for his service and Quality of Service (QoS) requirement user's job. Finally, we quantify the performance of the strategies via rigorous simulation studies.
Three-Dimensional Solution Structure of the Extracellular Region of the Complement Regulatory Protein CD59, a New Cell-Surface Protein Domain Related to Snake Venom Neurotoxins (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThree-Dimensional Solution Structure of the Extracellular Region of the Complement Regulatory Protein CD59, a New Cell-Surface Protein Domain Related to Snake Venom NeurotoxinsBruno Kieffer, Paul C. Driscoll, Iain D. Campbell, Antony C. Willis, P. Anton van der Merwe, and Simon J. DavisCite this: Biochemistry 1994, 33, 15, 4471–4482Publication Date (Print):April 19, 1994Publication History Published online1 May 2002Published inissue 19 April 1994https://pubs.acs.org/doi/10.1021/bi00181a006https://doi.org/10.1021/bi00181a006research-articleACS PublicationsRequest reuse permissionsArticle Views304Altmetric-Citations116LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Engineering Cytochrome P450s for Enantioselective Cyclopropenation of Internal Alkynes (2020)

We report a biocatalytic platform of engineered cytochrome P450 enzymes to carry out efficient cyclopropene synthesis via carbene transfer to internal alkynes. Directed evolution of a serine-ligated P450 variant, P411-<b>C10</b>, yielded a lineage of engineered P411 enzymes that together accommodate a variety of internal aromatic alkynes as substrates for cyclopropenation with unprecedented efficiencies and stereoselectivities (up to 5760 TTN, and all with >99.9% ee). Using an internal aliphatic alkyne bearing a propargylic ether group, different P411 variants can selectively catalyze cyclopropene formation, carbene insertion into a propargylic C-H bond or [3 + 2]-cycloaddition. This tunable reaction selectivity further highlights the benefit of using genetically encoded catalysts to address chemoselectivity challenges.
Efficient SIMD Arithmetic Modulo a Mersenne Number (2011)

This paper describes carry-less arithmetic operations modulo an integer 2^M-1 in the thousand-bit range, targeted at single instruction multiple data platforms and applications where overall throughput is the main performance criterion. Using an implementation on a cluster of PlayStation 3 game consoles a new record was set for the elliptic curve method for integer factorization.
Requirement for ERK Activation in Cisplatin-induced Apoptosis (2000)

Cisplatin activates multiple signal transduction pathways involved in coordinating cellular responses to stress. Here we demonstrate a requirement for extracellular signal-regulated protein kinase (ERK), a member of the mitogen-activated protein kinase family in mediating cisplatin-induced apoptosis of human cervical carcinoma HeLa cells. Cisplatin treatment resulted in dose- and time- dependent activation of ERK. That elevated ERK activity contributed to cell death by cisplatin was supported by several observations: 1) PD98059 and U0126, chemical inhibitors of the MEK/ERK signaling pathway, prevented apoptosis; 2) pretreatment of cells with TPA, an activator of the ERK pathway, enhanced their sensitivity to cisplatin; 3) suramin, a growth factor receptor antagonist that greatly suppressed ERK activation, likewise inhibited cisplatin-induced apoptosis; and, finally, 4) HeLa cell variants selected for cisplatin resistance showed reduced activation of ERK following cisplatin treatment. Cisplatin-induced apoptosis was associated with cytochrome c release and subsequent caspase-3 activation, both of which could be prevented by treatment with the MEK inhibitors. However, the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone protected HeLa cells against apoptosis without affecting ERK activation. Taken together, our findings suggest that ERK activation plays an active role in mediating cisplatin-induced apoptosis of HeLa cells and functions upstream of caspase activation to initiate the apoptotic signal.
Terminal Chains as a Tool To Modulate the Properties of Bent-Core Liquid Crystals (2009)

Two series of bent-shaped liquid crystals derived from 4,4′-diphenylmethane and 3,4′-biphenylene moieties have been prepared and studied. The research, focused on the effect of the terminal chains on the mesogenic properties of bent-core compounds, demonstrates that they can be used as a tool to control their liquid crystal behavior. Together with achiral and chiral alkoxy tails, thioalkoxy chains and unusual terminal structures on bent-core mesogens such as oxyethylene moieties or unsaturated tails of different lengths have been investigated. Mesomorphism as well as dielectric responses of the new materials are reported and discussed in light of structural considerations. Interesting results concerning lowering of transition temperatures, mesophase vitrification, or columnar−lamellar sequences have been achieved by the incorporation of these terminal chains.
Large-scale isolation of Dane particles from plasma containing hepatitis B antigen and deomnstration of circular double-stranded DNA molecule extruding directly from their cores. (1976)

A method was developed to isolate, on a large scale, Dane particles from five liters of pooled plasma of asymptomatic carriers of hepatitis B antigen. It involved three successive ultracentrifugation procedures; the final preparation was more than 98% pure in Dane particles. Purified Dane particles had the density of 1.23 to 1.24 g/cm3. The concentration of nucleic acids in the preparation containing purified Dane particles was too low to be detected either by chemical or by spectrophotometric method. However, a circular double-stranded DNA molecule extruding directly from the core of Dane particles was clearly demonstrated by elelctron microscopic observations. The cores of Dane particles (hepatitis B core antigen; HBCAg) were prepared by treating the Dane particle preparation with mercaptoethanol and Nonidet P-40. They were sufficient both in purity and amounts to allow the determination of antibody to HBCAg by an immune adherence hamagglutination method.
Plasma extravasation induced by dietary supplemented histamine in histamine-free mice (2002)

Histidine decarboxylase (HDC) synthesizes endogenous histamine from histidine in mammals. To evaluate the role of histamine in skin allergic reaction, we used HDC gene knockout mice lacking histamine. No plasma extravasation reaction was observed in HDC-/- mice after passive cutaneous anaphylaxis (PCA) test. Compound 48/80, a mast cell granule depletor, produced plasma extravasation inHDC+/+ mice but no extravasation in HDC-/- mice. Interestingly, orally administered histamine was distributed in the skin in HDC-/- mice and in these histamine-supplemented mice the plasma extravasation reaction was observed after the injection of compound 48/80 and the PCA test. Cultured bone marrow-derived mast cells of HDC-/- mice took up histamine from the histamine-supplemented medium into the secretory granules. The absorbed histamine was released in response to the same antigen and antibody combination used as in PCA test. In contrast to the immediate-type response, the delayed-type hypersensitive response, observed as a thickening of the ear skin after trinitrochlorobenzene challenge (following sensitization), showed no differences between HDC+/+ and HDC-/- mice. Therefore, among the allergic skin reactions, histamine is revealed to be an important mediator especially for the plasma extravasation in an immediate-type allergy model.
A Noncontact Ultrasonic Platform for Structural Inspection (2011)

Miniature robotic vehicles are receiving increasing attention for use in nondestructive testing (NDE) due to their attractiveness in terms of cost, safety, and their accessibility to areas where manual inspection is not practical. Conventional ultrasonic inspection requires the provision of a suitable coupling liquid between the probe and the structure under test. This necessitates either an on board reservoir or umbilical providing a constant flow of coupling fluid, neither of which are practical for a fleet of miniature robotic inspection vehicles. Air-coupled ultrasound offers the possibility of couplant-free ultrasonic inspection. This paper describes the sensing methodology, hardware platform and algorithms used to integrate an air-coupled ultrasonic inspection payload into a miniature robotic vehicle platform. The work takes account of the robot's inherent positional uncertainty when constructing an image of the test specimen from aggregated sensor measurements. This paper concludes with the results of an automatic inspection of a aluminium sample.