gebhart/patrepeval huggingface dataset:
Isomerization of Alkanes. I. Effect of Olefins upon the Isomerization of n-Butane in the Presence of Aluminum Halide—Hydrogen Halide Catalyst (1946)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIsomerization of Alkanes. I. Effect of Olefins upon the Isomerization of n-Butane in the Presence of Aluminum Halide—Hydrogen Halide CatalystHerman Pines and R. C. WackherCite this: J. Am. Chem. Soc. 1946, 68, 4, 595–599Publication Date (Print):April 1, 1946Publication History Published online1 May 2002Published inissue 1 April 1946https://pubs.acs.org/doi/10.1021/ja01208a020https://doi.org/10.1021/ja01208a020research-articleACS PublicationsRequest reuse permissionsArticle Views174Altmetric-Citations37LEARN 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
Reversible Block of Mouse Neural Stem Cell Differentiation in the Absence of Dicer and MicroRNAs (2010)

The block in differentiation due to loss of Dicer and microRNAs is reversible and the significantly altered phenotype of Dicer-null NS cells does not constitute a permanent transformation. We conclude that Dicer and microRNAs function in this system to maintain the neural stem cell phenotype and to facilitate the completion of differentiation.
Speciation and Thermodynamics of Sulfur Vapor (2004)

Abstract For Abstract see ChemInform Abstract in Full Text.
[Long-term antidepressive medication-- an increased anesthetic risk?]. (1990)

Antidepressants inhibit the re-uptake of norepinephrine at the monoaminergic synapse from the synaptic fissure, leading in this way to an increased sensitivity to catecholamines. In addition, antidepressants have alpha1-, H1- and H2-receptor blocking effects and also anticholinergic effects; the tricyclic antidepressants in particular are known for these properties. A few animal experiments and some case reports indicate that a long-term treatment with these substances can lead to intra-operative blood pressure fluctuations, tachycardia and arrhythmias. Therefore a number of authors recommend that antidepressants be withdrawn 3 days before a planned operation. In view of the pharmacokinetics of these substances and the long-term adapting processes at the monoaminergic synapse this period is certainly too short to achieve complete loss of effectiveness. Other authors think preoperative withdrawal is not indicated if there is careful intraoperative monitoring. We agree with the latter opinion. Inhalation anesthesia with isoflurane or enflurane should be preferred. The muscle relaxant pancuronium should not be used, and exogenous intake of catecholamines should be avoided. Opiates seem to have a positive effect on cardiac stability. Benzodiazepines show the least interactions with antidepressants and are therefore recommended for premedication. In the postoperative period the possibility of an anticholinergic syndrome has to be considered.
Outcomes with Anti-Tumour Necrosis Factor-Alpha Therapy and Serology in Patients with<i>Denovo</i>Crohn’s Disease After Ileal Pouch Anal Anastomosis (2016)

I2 serology may possibly help identify patients who have developed or are at risk for developing denovo CD. Anti-TNFα therapy for denovo CD after IPAA can help prevent permanent ileostomy in almost 75% of cases, even in patients who previously failed anti-TNFα treatment before surgery.
Chemical Aspects of Fusion Technology (1989)

Abstract Managing thermally controlled nuclear fusion will certainly be regarded one day as one of the most successful accomplishments in nuclear physics. At the same time, however, it will represent a technical achievement unparalleled in the history of science and engineering. This in turn would mean, in retrospect, that decisive contributions had to come from a number of disciplines as diverse as materials and engineering sciences and classical chemistry, and that the same collaboration will have to continue in the future in order to reach the ultimate goal, to construct a reactor capable of producing energy from almost inexhaustible source materials (fuels), such as deuterium and lithium. What is the chemist's role in this development? Similarly as in the development of fission reactors, i.e., the nuclear power plants currently in operation, chemists will have to ensure the existence of a reliable fuel cycle–starting from the availability, storage and reprocessing of the fuel through to the provision for safe storage of the waste. In this review article an attempt will be made to outline the problems associated with these tasks and the approaches to be made by the chemist in solving them.
Impaired immune responses toward alloantigens and tumor cells but normal thymic selection in mice deficient in the β2 integrin leukocyte function-associated antigen-1 (1996)

We have generated mice deficient in the beta2 integrin LFA-1 by targeted disruption of the CD11a gene in embryonic stem cells. In vitro LFA-1 -/- cells exhibit a delayed proliferative response toward alloantigens in the MLR. In vivo the host-vs-graft reaction toward injected allogeneic cells is also reduced. Alloantigen-specific CTLs generated from LFA-1 -/- mice are impaired in their cytotoxic activity toward allogeneic spleen cells as well as cell line targets. The proliferative response of LFA-1 -/- splenocytes following stimulation by LPS, PMA plus ionomycin, or immobilized anti-CD3epsilon mAb is normal, but Con A-stimulated proliferation is greatly diminished. We observe typical edema formation in a delayed type hypersensitivity reaction to SRBC with normal extravasation of leukocytes and demonstrate recruitment of neutrophils to an LPS-induced inflammatory site in these mice, suggesting that LFA-1 does not play an essential role in lymphocyte homing and leukocyte extravasation. We further show that LFA-1 -/- mice are susceptible to metastasis of B16 melanoma tumors, although their in vitro NK cell activity appears normal. A study of LFA-1 -/- mice expressing transgenic TCRs indicates that thymic maturation and selection of T cells are unaffected by the loss of LFA-1. Our results indicate that LFA-1 is important for alloantigen-triggered T cell proliferation and cytotoxicity, for Con A stimulation of T cells, and in tumor rejection. It does not appear to play an essential role in lymphocyte homing and leukocyte extravasation or in T cell maturation and selection in the thymus.
Human hepatic CYP1A1 and CYP1A2 content, determined with specific anti-peptide antibodies, correlates with the mutagenic activation of PhIP (1993)

Mono-specific antibodies targeted to human CYP1A1 and CYP1A2 have been produced by immunizing rabbits with protein conjugates of short synthetic peptides corresponding to residues 290-297 and 284-296 respectively, of these enzymes. The antibody targeted to CYP1A1 bound in immunoblotting to the recombinant protein expressed in yeast but did not bind to any human hepatic microsomal protein, whereas the antibody targeted to CYP1A2 bound only to this enzyme in immunoblotting of human hepatic microsomal fractions and did not recognize recombinant human CYP1A1. The intensity of hepatic microsomal CYP1A2 immunoreactivity (n = 5) correlated significantly with a number of activities characteristic of this enzyme: phenacetin O-deethylase (POD), ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase activities and the ability to activate the dietary carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), to a mutagen. The anti-CYP1A2 anti-peptide antibody consistently inhibited both POD and EROD activities, but inhibition was incomplete (28%). In view of the known (> 90%) contribution of CYP1A2 to these activities and the correlation with antibody binding, this is consonant with an epitope for the anti-CYP1A2 anti-peptide antibody that forms the edge of a functionally important proinhibitory surface region previously identified in rat cytochromes CYP1A. CYP1A2 immunoreactivity determined by immunoblotting correlated significantly with the ability of human hepatic microsomal fractions to activate 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP), another dietary carcinogen, to a mutagen. It is concluded that CYP1A1 is absent from human liver and that CYP1A2 is likely to be a major catalyst in the hepatic activation of PhIP.
Long-Term Experimental Evolution in Escherichia coli. I. Adaptation and Divergence During 2,000 Generations (1991)

We assess the degree to which adaptation to a uniform environment among independently evolving asexual populations is associated with increasing divergence of those populations. In addition, we are concerned with the pattern of adaptation itself, particularly whether the rate of increase in mean fitness tends to decline with the number of generations of selection in a constant environment. The correspondence between the rate of increase in mean fitness and the within-population genetic variance of fitness, as expected from Fisher's fundamental theorem, is also addressed. Twelve Escherichia coli populations were founded from a single clonal ancestor and allowed to evolve for 2,000 generations. Mean fitness increased by about 37%. However, the rate of increase in mean fitness was slower in later generations. There was no statistically significant within-population genetic variance of fitness, but there was significant between-population variance. Although the estimated genetic variation in fitness within populations was not statistically significant, it was consistent in magnitude with theoretical expectations. Similarly, the variance of mean fitness between populations was consistent with a model that incorporated stochastic variation in the timing and order of substitutions at a finite number of nonepistatic loci, coupled with substitutional delays and interference between substitutions arising from clonality. These results, taken as a whole, are consistent with theoretical expectations that do not invoke divergence due to multiple fitness peaks in a Wrightian evolutionary landscape.
Fast continuous motion of the field of view in magnetic particle imaging (2013)

When shifting the FOV during imaging, artifacts arise when the shift per volume encoding time is larger than the resolution. Up to shift velocities of about 1 m/s, these can be removed by compensating the system function for the rapid translation. Fast continuous FOV shifts may be used to rapidly steer a single imaging volume to a region of interest or to achieve large spatial coverage by repeatedly sweeping the FOV through a volume of interest.
Origin and Bidirectional Orientation of DNA Replication in Coliphage Lambda (1971)

In the lysogenic, integrated state coliphage λ DNA is replicated as a part of the bacterial chromosome. After prophage induction or after infection, replication of λ DNA becomes autonomous and much more rapid than that of the host genome. According to current evidence, several elements are required for autonomous λ DNA replication. These include (1) at least part of the host replication system, (2) the products of λ genes O and P , (3) the site on the λ genome where replication originates and which will be designated as the origin of replication ( ori ) or the replicator, and (4) activation of the replicator, which requires rightward transcription of any part of the short λ DNA segment containing the ori site (see Thomas and Bertani, 1964; Dove et al., 1969, and this volume). The first two requirements can be satisfied in trans , whereas requirements (3) and (4) can be fulfilled only in cis . The present study was undertaken to determine the molecular location of the origin of autonomous λ DNA replication ( ori ), the orientation of the in situ replication of the induced but not excised λ prophage, and the effect of mutations in the phage or host genome on λ DNA replication. It was found that (a) the ori site is located just to the left of gene O at approximately 80.2 ± 0.5% of the λ genome length (measured from the left terminus of the mature phage DNA), and (b) the orientation of replication is bidirectional, proceeding both to the left...
Hybrid energy storage: the merging of battery and supercapacitor chemistries (2015)

The hybrid approach allows for a reinforcing combination of properties of dissimilar components in synergic combinations. From hybrid materials to hybrid devices the approach offers opportunities to tackle much needed improvements in the performance of energy storage devices. This paper reviews the different approaches and scales of hybrids, materials, electrodes and devices striving to advance along the diagonal of Ragone plots, providing enhanced energy and power densities by combining battery and supercapacitor materials and storage mechanisms. Furthermore, some theoretical aspects are considered regarding the possible hybrid combinations and tactics for the fabrication of optimized final devices. All of it aiming at enhancing the electrochemical performance of energy storage systems.
Covalent Immobilization of a Molecular Catalyst on Cu<sub>2</sub>O Photocathodes for CO<sub>2</sub> Reduction (2016)

Sunlight-driven CO2 reduction is a promising way to close the anthropogenic carbon cycle. Integrating light harvester and electrocatalyst functions into a single photoelectrode, which converts solar energy and CO2 directly into reduced carbon species, is under extensive investigation. The immobilization of rhenium-containing CO2 reduction catalysts on the surface of a protected Cu2O-based photocathode allows for the design of a photofunctional unit combining the advantages of molecular catalysts with inorganic photoabsorbers. To achieve large current densities, a nanostructured TiO2 scaffold, processed at low temperature, was deposited on the surface of protected Cu2O photocathodes. This led to a 40-fold enhancement of the catalytic photocurrent as compared to planar devices, resulting in the sunlight-driven evolution of CO at large current densities and with high selectivity. Potentiodynamic and spectroelectrochemical measurements point toward a similar mechanism for the catalyst in the bound and unbound form, whereas no significant production of CO was observed from the scaffold in the absence of a molecular catalyst.
Taxol Related Diterpenes from the Roots of Taxus yunnanensis (1994)

Bbstract-Four new taxol related diterpenes were isolated from the roots of T a x u s yunnanensis together with taxol, cephalomamine, 10-deacetyltaxol, and 10deacetylcephalomamine and their structures were elucidated by spectroscopic means.The natural product taxol ( 1 ) l has brought great promise for Sufferers of ovarian and breast cancer, but its scarcity limits its application to small number of patients.The search for new compounds with similar bioactivity to taxol or semisynthetic precursors of taxol therefore is imperative.Our research on the roots of T a x u s yunnanensis collected in the suburbs of Kunming, Yunnan, China led to the isolation of compound, taxuyunnanine A ( 2 ) 2 which shaved comparable cytotoxity to that of taxol 1 .On further investigation, four new taxuyunnanine A relateU compounds were isolated together
Substaging of T1 bladder carcinoma based on the depth of invasion as measured by micrometer (1999)

The results of the current study show that substaging of T1 bladder carcinoma according to the depth of invasion (as measured by micrometer) provides significant prognostic information. Therefore the authors recommend that it be reported in specimens obtained by TURB.
Immune enhancement of pulmonary clearance of nontypable Haemophilus influenzae (1988)

BALB/c mice systemically immunized by intraperitoneal injection with whole, viable cells of two different strains of nontypable Haemophilus influenzae (NTHI) exhibited a markedly enhanced ability to clear the homologous strain of NTHI from the lower respiratory tract. Immunization did not influence the number of phagocytic cells recovered by bronchoalveolar lavage from mice before or after intrapulmonary challenge with NTHI. Immunization also induced the synthesis of relatively large quantities of NTHI-directed antibodies which were detectable in both the bloodstream and the alveolar spaces of the lung. Radioimmunoprecipitation and Western blot (immunoblot) analyses indicated that these antibodies were directed against both the proteins and lipooligosaccharide (LOS) in the NTHI outer membrane. Bactericidal and opsonophagocytic assays determined that the NTHI-directed antibodies in the serum were functional and able to kill or opsonize the homologous NTHI strain. Mice immunized with an NTHI major outer membrane protein-LOS complex also had an increased ability to effect pulmonary clearance of NTHI. Serum and bronchoalveolar lavage fluid collected from these animals immunized with the outer membrane protein-LOS complex contained relatively high levels of antibodies to both of these antigens. The serum from these animals also possessed bactericidal and opsonic activity against the homologous NTHI strain. These results indicate that systemic immunization can enhance the ability of experimental animals to clear NTHI from the lower respiratory tract and suggest that immunoprophylaxis of NTHI pulmonary disease may be feasible.
A novel two-electron mixed-valence Ir(II)–Ir(0) complex (1999)

An IrII–Ir0 mixed-valence complex, Ir2{MeN[P(OEtF3)2]2}3Cl2 (OEtF3 = OCH2CF3), has been prepared by treatment of Ir2Cl2(cod)2 with 3 equiv. of MeN[P(OEtF3)2]2; donor ligands (CNBut and PEt3) add to the binuclear core, which provides a novel platform for the multielectron activation of small molecule substrates.
View changes in augmented reality computer-aided-drawing (2005)

A prototype augmented reality computer-aided-drawing (AR CAD) prototype aimed at supporting a design detailing and review process has been developed. Utilizing head-mounted displays, AR CAD supports users in manipulating design models with two possible view change mechanisms---observer movement around the virtual object (model) or rotation of the virtual object. Previous studies in scene recognition across views of real objects yielded performances that were better under observer movement conditions, than under object rotation conditions. Based on these studies, it is hypothesized that the perception of 3D designs in an augmented scene from the AR CAD prototype is also better when changing views by observer movement than by model rotation. This study presents an experiment to test this hypothesis, so as to address the question of the appropriate mechanisms for view change that best support the perception of 3D designs presented in an augmented reality platform. The findings from the experiment suggest that an individual's perception of 3D designs in an augmented scene from AR CAD depends, in part, on the type of view change, showing that performance was better after observer movement than after model rotation.
A Method for Determining the Propagation Constants of Plastics at Ultrasonic Frequencies (1951)

A pulse technique particularly suited to dissipative materials is described for measuring attenuation and phase shift constants of plastics, using either transverse or longitudinal waves in the frequency range of 5–50 Mc. A thin wafer of the material under test is placed between two identical fused silica buffers; and waves generated by quartz crystals at the ends of the assembly are transmitted simultaneously through the specimen in both directions. Comparison of transmitted and reflected components by means of a special balancing circuit provides information from which the complex propagation constant can be calculated, and hence dynamic rigidities and viscosities. Illustrative data for polyethylene and Nylon are given.
<title>A most spectrum-efficient duplexing system: CDD</title> (2001)

The game to play in wireless communications when it comes to increasing spectrum efficiency is to eliminate interference. Currently, all cellular systems use FDD (Frequency Division Duplexing) in an attempt to eliminate the interference from the adjacent cells. Through the use of many technologies only one type of interference remains and that is the adjacent base-tohome mobile interference. TDD (Time Division Duplexing) has not been used for mobile cellular systems, not only because of the adjacent base-to-home mobile interference, but also because of the additional adjacent base-to-home base interference, and adjacent mobile-to-home mobile interference. Therefore, TDD can only be used for small, confined area systems. CDD (Code Division Duplexing) can eliminate all three kinds of interference; the adjacent base-to-home mobile, the adjacent baseto-home base, and the adjacent mobile- to- home in cellular systems. Eliminating each of these interferences makes CDD the most spectrum efficient duplexing system. This talk will elaborate on a set of smart codes, which will make an efficient CDD system a reality.
Human stick balancing: Tuning Lèvy flights to improve balance control (2004)

State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lèvy flight. The Lèvy index, alpha, is approximately 0.9; a value close to optimal for a random search. With increased skill, the index alpha does not change. However, the tails of the Lèvy distribution become broader. These observations suggest a Lèvy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill level increases. Measurements of the cross-correlation between the position of the tip of the stick and the fingertip demonstrate that the role of closed-loop feedback changes with increased skill. Moreover, estimation of the neural latencies for stick balancing show that for a given stick length, the latency increases with skill level. It is suggested that the neural control for stick balancing involves a mechanism in which brief intervals of consciously generated, corrective movements alternate with longer intervals of prediction-free control. With learning the truncation of the Lèvy flight becomes better optimized for balance control and hence the time between successive conscious corrections increases. These observations provide the first evidence that changes in a Lèvy flight may have functional significance for the nervous system. This work has implications for the control of balancing problems ranging from falling in the elderly to the design of two-legged robots and earthquake proof buildings.