gebhart/patrepeval huggingface dataset:
Cell Biology Education (2002)

We have not been very systematic about our quest to improve teaching, even though we value it highly and frequently do well at it.I am struck, for example, by the lack of conversation about what pedagogy means, and what makes it successful.It is our profession, yet it is mysteriously absent from our professional discourse.Here we are, engaged in an activity that is vital to ourselves, our students, and our public-yet we speak of how to do it, if at all, as though it had no data base, lacked a history, and offered no innovative challenges.(
Tridentate ligands derived from substitution in the methyl group of 8-hydroxyquinaldine (1967)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTridentate ligands derived from substitution in the methyl group of 8-hydroxyquinaldineRobert L. Stevenson and Henry. FreiserCite this: Anal. Chem. 1967, 39, 12, 1354–1358Publication Date (Print):October 1, 1967Publication History Published online1 May 2002Published inissue 1 October 1967https://pubs.acs.org/doi/10.1021/ac60256a013https://doi.org/10.1021/ac60256a013research-articleACS PublicationsRequest reuse permissionsArticle Views213Altmetric-Citations31LEARN 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
Ecogeographic variation in human nasal passages (2008)

Theoretically, individuals whose ancestors evolved in cold and/or dry climates should have greater nasal mucosal surface area relative to air volume of the nasal passages than individuals whose ancestors evolved in warm, humid climates. A high surface-area-to-volume (SA/V) ratio allows relatively more air to come in contact with the mucosa and facilitates more efficient heat and moisture exchange during inspiration and expiration, which would be adaptive in a cold, dry environment. Conversely, a low SA/V ratio is not as efficient at recapturing heat and moisture during expiration and allows for better heat dissipation, which would be adaptive in a warm, humid environment. To test this hypothesis, cross-sectional measurements of the nasal passages that reflect surface area and volume were collected from a sample of CT scans of patients of European and African ancestry. Results indicate that individuals of European descent do have higher SA/V ratios than individuals of African descent, but only when decongested. Otherwise, the two groups show little difference. This pattern of variation may be due to selection for different SA/V configurations during times of physical exertion, which has been shown to elicit decongestion. Relationships between linear measurements of the skeletal nasal aperture and cavity and cross-sectional dimensions were also examined. Contrary to predictions, the nasal index, the ratio of nasal breadth to nasal height, is not strongly correlated with internal dimensions. However, differences between the nasal indices of the two groups are highly significant. These results may be indicative of different adaptive solutions to the same problem.
The intracellular bacterium Rhodococcus equi requires Mac-1 to bind to mammalian cells (1993)

Rhodococcus equi is a facultative intracellular bacterium of macrophages that causes disease in immunocompromised individuals, particularly those with AIDS. In this report, we demonstrate that R. equi binding to mammalian cells requires complement and is mediated primarily by the leukocyte complement receptor, Mac-1. Bacteria bind to macrophages poorly unless exogenous complement is added to the incubation medium. The addition of fresh nonimmune serum, which contains no detectable antibodies to R. equi, greatly enhances bacterial binding to macrophages, whereas heat inactivation of this serum or immunological depletion of C3 from the serum reduces binding to levels only slightly higher than those of binding under serum-free conditions. Human serum depleted of C2 or C4 is fully opsonic, indicating that complement activation and fixation occur by the alternative pathway. The serum-dependent binding of rhodococci to macrophages is mediated primarily by the macrophage complement receptor type 3, Mac-1 (CD11b/CD18). Bacteria do not bind to fibroblastoid or epithelial cells that lack this receptor. Most of the bacterial binding to macrophages is inhibited by a monoclonal antibody to Mac-1 but is unaffected by a monoclonal antibody to complement receptor type 1. Furthermore, opsonized, but not unopsonized, bacteria bind to purified Mac-1 immobilized on plastic. In addition, in the presence of opsonic complement, rhodococci bind efficiently to fibroblastoid cells transfected with cloned Mac-1 but relatively poorly to cells transfected with the complement receptor type 1. Hence, R. equi fixes complement by activating the alternative complement pathway, and this fixation is a requirement for bacterial adhesion and invasion. Furthermore, complement fixation defines rhodococcal host cell tropism, since R. equi binds specifically and exclusively to cells expressing Mac-1.
Conditioned Behavior in Drosophila melanogaster (1974)

Populations of Drosophila were trained by alternately exposing them to two odorants, one coupled with electric shock. On testing, the flies avoided the shock-associated odor. Pseudoconditioning, excitatory states, odor preference, sensitization, habituation, and subjective bias have been eliminated as explanations. The selective avoidance can be extinguished by retraining. All flies in the population have equal probability of expressing this behavior. Memory persists for 24 hr. Another paradigm has been developed in which flies learn to discriminate between light sources of different color.
Human serum amyloid P component. cDNA isolation, complete sequence of pre-serum amyloid P component, and localization of the gene to chromosome 1. (1985)

Complementary DNA clones corresponding to the human serum amyloid P component (SAP) were isolated, and the complete nucleotide and derived amino acid sequence of preSAP was determined. PreSAP biosynthesis is directed by a 1.1-kilobase mRNA. Synthesis and postsynthetic processing of preSAP in Xenopus oocytes result in secretion of a protein with mobility similar to native purified SAP when analyzed by sodium dodecyl sulfate gel electrophoresis. The human SAP gene is on chromosome 1, probably closely linked to the gene for C-reactive protein which encodes the related acute phase reactant found in human plasma.
Receptor-mediated endocytosis of vitronectin is regulated by its conformational state (1993)

Vitronectin is a structurally labile molecule with a native, non-heparin binding form and a conformationally altered, heparin binding form. To understand the physiological significance of the two conformers of vitronectin, we examined the metabolism of both conformers by cultured human skin fibroblasts. Both native and altered vitronectin bound to confluent fibroblast monolayers. Both conformers of vitronectin competed equally well for the binding of altered vitronectin to the cell layer, suggesting that both conformers bound to the same site in the cell layer. In contrast, 125I-altered vitronectin, but not 125I-native vitronectin, was degraded to trichloroacetic acid-soluble radioactivity by the fibroblast monolayer. Degradation of vitronectin was saturable, sensitive to chloroquine, and occurred intracellularly, suggesting that vitronectin was degraded through a lysosomal pathway. Heparin and thrombospondin inhibited the degradation of altered vitronectin. The degradation of native vitronectin was induced by addition of gamma-thrombin which exposes vitronectin's cryptic heparin-binding domain. These studies suggest that the heparin-binding domain in vitronectin is required for the clearance of vitronectin from the matrix. In addition, these data demonstrate that the conformation of vitronectin regulates its half-life in the matrix. These studies provide the first evidence for a distinct function for the conformers of vitronectin.
Inhibition of DNA Methylation and Reactivation of Silenced Genes by Zebularine (2003)

Zebularine is a stable DNA demethylating agent and the first drug in its class able to reactivate an epigenetically silenced gene by oral administration.
Cooperativity Between T Cell Receptor Complexes Revealed by Conformational Mutants of CD3ɛ (2009)

The CD3epsilon subunit of the T cell receptor (TCR) complex undergoes a conformational change upon ligand binding that is thought to be important for the activation of T cells. To study this process, we built a molecular dynamics model of the transmission of the conformational change within the ectodomains of CD3. The model showed that the CD3 dimers underwent a stiffening effect that was funneled to the base of the CD3epsilon subunit. Mutation of two relevant amino acid residues blocked transmission of the conformational change and the differentiation and activation of T cells. Furthermore, this inhibition occurred even in the presence of excess endogenous CD3epsilon subunits. These results emphasize the importance of the conformational change in CD3epsilon for the activation of T cells and suggest the existence of unforeseen cooperativity between TCR complexes.
Expression of two csg operons is required for production of fibronectin‐ and Congo red‐binding curli polymers in Escherichia coli K‐12 (1995)

Two divergently transcribed operons in Escherichia coli required for the expression of fibronectin- and Congo red-binding curli polymers were identified and characterized by transposon mutagenesis, sequencing and transcriptional analyses, as well as for their ability to produce the curli subunit protein. The csgBA operon encodes CsgA, the major subunit protein of the fibre, and CsgB, a protein with sequence homology to CsgA. A non-polar csgB mutant is unaffected in its production of CsgA, but the subunit protein is not assembled into insoluble fibre polymers. A third open reading frame, orfC, positioned downstream of csgA may affect some functional property of curli since an insertion in this putative gene abolishes the autoagglutinating ability typical of curliated cells without affecting the production of the fibre. The promoter for the oppositely transcribed csgDEFG operon was identified by primer extension and shown, like the csgBA promoter, to be dependent upon the alternate stationary phase-specific sigma factor sigma s in wild-type cells, but not in mutants lacking the nucleoid associated protein H-NS. Insertions in csgD abolish completely trancription from the csgBA promoter. Therefore, any regulatory effect on the csgBA promoter might be secondary to events controlling the csgDEFG promoter and/or activation of CsgD. Insertions in csgE, csgF and csgG abolish curli formation but allow CsgA expression suggesting that one or more of these gene products are involved in secretion/assembly of the CsgA subunit protein. No amino acid sequence homologies were found between the CsgE, CsgF and CsgG proteins and secretion/assembly proteins for other known bacterial fibres, suggesting that the formation of curli follows a novel pathway.
Improving TCI/IP performance over wireless networks (1995)

TCP is a reliable transport protocol tuned to perform well in traditional networks made up of links with low bit-error rates. Networks with higher bit-error rates, such as those with wireless links and mobile hosts, violate many of the assumptions made by TCP, causing degraded end-to-end performance. In tbis paper, we describe the design and implementation of a simple protocol, called the snoop protocol, that improves TCP performance in wireless networks. The protocol modifies network-layer software mainly at a base station and preserves end-to-end TCP semantics. The main idea of the protocol is to cache packets at the base station and perform local retransmissions across the wireless link. We have implemented the snoop protocol on a wireless testbed consisting of IBM ThinkPad laptops and i486 base stations communicating over an AT&T Wavelan. Our experiments show that it is significantly more robust at dealing with unreliable wireless links as compared to normal TCP; we have achieved throughput speedups of up to 20 times over regular TCP in our experiments with the protocol.
非洲:生命源头的秘密(上) (1995)

直立人是极为成功的流动群体,事实上,他们的旅行十分顺利,人们最初发现的直立人化石距离他们原来的非洲家园有好几千公里.在19世纪90年代,尤基尼·多布尔斯,一位富于冒险精神的荷兰物理学家,他加入了荷兰军队以此为藉口到达了荷兰属的东印度群岛(即现在的印度尼西亚).多布尔斯同意查理·达尔文的理论,认为早期人类与大猿有着密切的联系.因为在东印度群岛上有猩猩存在,所以多布尔斯认为这里可能拥有“丢失链”的化石.
Chronic daily headache (2000)

Primary chronic daily headache can be subclassified into disorders of short duration (<4 h/attack) including chronic cluster and disorders of long duration (> or =4 h/attack). Primary chronic daily headache disorders of long duration include chronic tension-type headache, chronic daily migraine (previously called transformed migraine), new daily persistent headache, and hemicrania continua. Four to 5% of the general population have primary chronic daily headache. Most chronic daily headache patients overuse analgesics or ergots. This article will consider recent insights into specific disorders, then psychiatric comorbidity, epidemiology, pathophysiology, and treatment.
The radiosensitizer nicotinamide inhibits arterial vasoconstriction (1994)

Nicotinamide (NA) is currently entering clinical trials as a radiosensitizer. A major component of its activity is the improvement of tumour oxygenation resulting from a reduction in microregional ischaemia. NA is known to reduce arterial blood pressure in rodents, suggesting a vascular component in its mechanism of action. We have used an ex vivo system to study the direct action of NA on the contractile properties of vascular smooth muscle. Isolated pieces of rat tail artery were internally perfused with Krebs' solution at a constant flow rate so that constriction of the arterial smooth muscle could be measured as an increase in perfusion pressure. Transient vasoconstrictor responses lasting up to 10 min were induced with bolus injections (10 microliters) of phenylephrine, at concentrations ranging from 10(-5) to 10(-2) M, into the internal perfusate whereas a constant increase in vasoconstrictor tone, giving perfusion pressures of 43-84 mmHg, was induced by constantly perfusing with PE (5 x 10(-6) M) or raising the K+ concentration of the Krebs' solution to 122 mM. The addition of NA to the perfusate significantly reduced the size of the transient vasoconstrictor responses in a dose-dependent manner and induced the precontracted vessels to relax. This action of NA could not be blocked either by N omega-nitro-L-arginine methyl ester (L-NAME), indomethacin or propranolol. We conclude that direct effects on supplying blood vessels probably contribute to the oxygenating action of NA in tumours, though the precise mechanism remains obscure.
Bioconjugation by Copper(I)-Catalyzed Azide-Alkyne [3 + 2] Cycloaddition (2003)

The copper-catalyzed cycloaddition reaction between azides and alkynes functions efficiently in aqueous solution in the presence of a tris(triazolyl)amine ligand. The process has been employed to make rapid and reliable covalent connections to micromolar concentrations of protein decorated with either of the reactive moieties. The chelating ligand plays a crucial role in stabilizing the Cu(I) oxidation state and protecting the protein from Cu(triazole)-induced denaturation. Because the azide and alkyne groups themselves are unreactive with protein residues or other biomolecules, their ligation is of potential utility as a general bioconjugation method.
Targeted Degradation of the Aryl Hydrocarbon Receptor by the PROTAC Approach: A Useful Chemical Genetic Tool (2007)

License to degrade. A chimeric small molecule or PROTAC (PROteolysis TArgeting Chimera) based on the chemopreventive natural product apigenin was developed (see scheme). The molecule was shown to target the aryl hydrocarbon receptor (AHR) for degradation by the proteasome.
Extended carrier lifetimes and diffusion in hybrid perovskites revealed by Hall effect and photoconductivity measurements (2016)

Impressive performance of hybrid perovskite solar cells reported in recent years still awaits a comprehensive understanding of its microscopic origins. In this work, the intrinsic Hall mobility and photocarrier recombination coefficient are directly measured in these materials in steady-state transport studies. The results show that electron-hole recombination and carrier trapping rates in hybrid perovskites are very low. The bimolecular recombination coefficient (10(-11) to 10(-10) cm(3) s(-1)) is found to be on par with that in the best direct-band inorganic semiconductors, even though the intrinsic Hall mobility in hybrid perovskites is considerably lower (up to 60 cm(2) V(-1) s(-1)). Measured here, steady-state carrier lifetimes (of up to 3 ms) and diffusion lengths (as long as 650 μm) are significantly longer than those in high-purity crystalline inorganic semiconductors. We suggest that these experimental findings are consistent with the polaronic nature of charge carriers, resulting from an interaction of charges with methylammonium dipoles.
Robot localisation using interval analysis (2004)

This paper describes a deterministic approach for the sensor-based localisation and navigation of a mobile robot. This approach is based on interval analysis and the robot equipped with ultrasonic sensors. For the localisation, it is assumed that the map is 2D and also it is assumed to be known a-priory to the robot. It has already been shown by Jaulin et.al. that mobile robot localisation and tracking using interval analysis and an interval model of the robot, with ultrasonic sensors only can be achieved. Here we use the same algorithm for robot localisation but without using an interval model of the robot. Instead the physical limitations of the robot is used to predict and track the robots position. In classical methods such as Kalman filters for robot localisation, the data association step is very complex and they are based on linearisation. Where as the method proposed here using interval analysis bypasses the data association step and deals with the problem as nonlinear and in a global way.
Strategy for the Selection of Scaffolds for Tissue Engineering (1995)

A strategy for developing scaffolding materials for prostheses capable of inducing tissue regeneration is presented. It is based on knowledge of the stimuli cells need to carry out their programs of division, morphogenesis, and differentiation, that is, of tissue building. The source of the stimulation is shown to be the extracellular matrix (ECM), in or on which cells in tissues live. A capsule view of the molecular diversity and the supramolecular architecture of the ECM is given with the idea that it can be imitated. The desired properties of scaffolding materials assembled from biological and engineering considerations allow the reader to evaluate biomaterials available for creating prostheses. Keeping in mind the ideal properties sought, a series of case histories is presented as a vehicle for examining prosthetic devices, and the materials used for them. Engineered or processed, naturally occurring, tissue replacements for articular cartilage, small caliber artery, periodontal tissues, cruciate ligament, and skin are reviewed from the point of view of how cells react to the scaffolds and how effectively a functional tissue replacement is restored in vivo. An approach to creating scaffolds by deducing their structure mathematically from their function in vivo is discussed as a first step in imitating the design of a body part. Finally touched on is the task of creating information-rich scaffolds like the ECM.
A Method for Micrometer Resolution Patterning of Primary Culture Neurons for SPM Analysis (2001)

In this work we present a method for ultra-fine patterning of primary culture neuron cell growth, which is compatible for scanning near-field optical atomic force microscopy (SNOAM) analysis. SNOAM uses near-field optics to break the fundamental diffraction limit imposed on normal microscopy. SNOAM can achieve sub-100 nm optical resolutions, but requires transparent, open substrates. The ability to do physiological measurements on patterns of neurons, combined with ultra high resolution optical and fluorescent analysis, is useful in the study of long-term potentiation. The patterning method consists of chemical guidance with an element of physical confinement and allows for ultra-fine patterning of neural growth on transparent glass substrates. Substrates consist of microfabricated perfluoropolymer barrier structures on glass. Poly-L-lysine was selectively deposited using a silicone-based microfluidic stencil aligned to the perfluoropolymer/glass substrate. Primary culture neurons were extracted from 8-day-old chicks and grown for 3 days to form good networks. This patterning system shows very specific growth with patterning separations down to the level of individual neurites. Fluorescent imaging was carried out on both cell viability during growth and immuno-tagged microtubule-associated proteins on the neurites. Neurons inside the patterned structures were imaged and analyzed with a tapping mode SNOAM.
Thiation of Nucleosides. II. Synthesis of 5-Methyl-2'-deoxycytidine and Related Pyrimidine Nucleosides1 (1959)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThiation of Nucleosides. II. Synthesis of 5-Methyl-2'-deoxycytidine and Related Pyrimidine Nucleosides1Jack J. Fox, Dina Van Praag, Iris Wempen, Iris L. Doerr, Loretta Cheong, Joseph E. Knoll, Maxwell L. Eidinoff, Aaron Bendich, and George Bosworth BrownCite this: J. Am. Chem. Soc. 1959, 81, 1, 178–187Publication Date (Print):January 1, 1959Publication History Published online1 May 2002Published inissue 1 January 1959https://pubs.acs.org/doi/10.1021/ja01510a042https://doi.org/10.1021/ja01510a042research-articleACS PublicationsRequest reuse permissionsArticle Views1136Altmetric-Citations203LEARN 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