gebhart/patrepeval huggingface dataset:
Highly Functionalised Pyroglutamates by Intramolecular Aldol Reactions: Towards the Pyroglutamate Skeleton of Oxazolomycin (1996)

Intramolecular aldol reactions of cis-N-acyloxazolidines 6a,b gave protected α-substituted pyroglutamates. The observed stereocontrol arises as a result of the chiral memory of the oxazolidine template, and regioselective enolate formation prior to ring closure. The major products, 10 and 12, have the correct relative stereochemistry for the oxazolomycin group of antitumour antibiotics.
C<sub>2</sub>H<sub>4</sub> adsorption on Cu(210), revisited: bonding nature and coverage effects (2016)

With the aid of density functional theory (DFT)-based calculations, we investigate the adsorption of C<sub>2</sub>H<sub>4</sub> on Cu(210).
Photoemission study of ammonia dissociation on Si(100) below 700 K (1987)

Ultraviolet and x-ray photoelectron spectroscopies (UPS and XPS) have been used to study the initial ${\mathrm{NH}}_{3}$ adsorption stage on the S(100)-2\ifmmode\times\else\texttimes\fi{}1 surface between room temperature (RT) and 700 K. Our results are markedly different from recently reported data, showing complete ${\mathrm{NH}}_{3}$ dissociation and surface dangling-bond (DB) saturation with H adatoms even below RT. While UPS features relevant to Si---H bonds (in dihydride at RT and monohydride near 600 K) are actually observed, other coadsorbed species labeled ${\mathrm{NH}}_{\mathrm{x}}$ are clearly identified in our photoemission experiments and contribute to the surface passivation. Thus only partial dissociation of ${\mathrm{NH}}_{3}$ occurs on Si(100) at least up to 550 K, and the initial thermal nitridation is not just rate limited by surface DB saturation with H. The present findings allow new insights into the mechanism of electron-beam-assisted nitridation at low temperature.
Surface modification strategies for (100)3C-SiC (1986)

Several surface modification techniques were performed in situ in an ultrahigh vacuum as part of a program to develop electrical contacts on the (100) face of cubic SiC. The Auger electron spectroscopy line shapes and peak-to-peak heights of the Si LVV and C KLL transitions indicated changes in surface stoichiometry, bonding, and short range order. Changes in the low energy electron diffraction pattern identified changes in the symmetry of long range ordering on the surface. Heating above 1050 °C depleted the surface of Si with an activation energy of 120 kcal/mol, resulting eventually in a disordered graphitic layer which was several atomic layers thick. Bombardment by Ar ions of energies greater than 1000 eV enhanced the Si to C ratio on the surface and destroyed the LEED pattern. Long range order was recovered by simultaneous heating and ion bombardment. Finally, adsorption of Cr on the Ar ion damaged surface and subsequent desorption left a reconstructed, p(2×1)Si enriched surface. Similar treatments with Al did not produce a surface reconstruction.
Direct-write graded index materials realized in protein hydrogels (2016)

The ability to create optical materials with arbitrary index distributions would prove transformative for optics design and applications. However, current fabrication techniques for graded index (GRIN) materials rely on diffusion profiles and therefore are unable to realize arbitrary distribution GRIN design. Here, we demonstrate the laser direct writing of graded index structures in protein-based hydrogels using multiphoton lithography. We show index changes spanning a range of 10−2, which is comparable with laser densified glass and polymer systems. Further, we demonstrate the conversion of these written density variation structures into SiO2, opening up the possibility of transforming GRIN hydrogels to a wide range of material systems.
Structure of Plant Cell Walls (1979)

Wild type Bacillus subtilis, when grown on beet araban, secretes into its culture medium an endo-arabanase and two arabinosidases. An alternate procedure to one previously described (Kaji A, T Saheki 1975 Biochim Biophys Acta 410: 354-360) has been developed for the purification of the endo-arabanase. The purified endo-arabanase is shown to be homogeneous by sodium dodecyl sulfate-urea disc gel electrophoresis (molecular weight approximately 32,000) and by isoelectric focusing (pI = 9.3). The endo-arabanase, acting on a branched araban substrate, has maximal activity at pH 6.0 and preferentially cleaves 5-linked arabinosyl residues. One of the arabinosidases (molecular weight approximately 65,000, pI = 5.3) has been purified to the point that it contains only one quantitatively minor contaminant, as shown by sodium dodecyl sulfate-urea disc gel electrophoresis and isoelectric focusing. The purified arabinosidase, acting on p-nitrophenyl-alpha-l-arabinofuranoside, has maximal activity at pH 6.5, and, when acting on a branched araban substrate, preferentially attacks nonreducing terminal arabinosyl residues linked to the 2 or 3 position of other arabinosyl residues. Neither of the two purified enzymes is capable of hydrolyzing a variety of carbohydrate substrates which lack arabinosidic linkages. The purified endo-arabinase is shown to be capable of releasing arabinosyl oligomers from the walls of suspension-cultured sycamore cells, thereby suggesting its usefulness as a probe in studying the structure of the araban component of primary cell walls.
Modified method of investigation of antioxidant activity in food and biological liquids (2003)

Nowadays the interest in investigation of free-radical processes is increasing among physiologysts, pathophysiologysts, physicians, dietologysts, etc. This is due to the connection of their role with influence on organs, tissues and cells, reproduction, cancerogenesis, atherogenesis and aging processes. The understanding of the role of bioradicals resulted in searching of external antioxidants which increase the activity of antioxydant protection system of organisms. However, the determination of physiological effect of external antioxidants needs the investigation of their utilization stages. There are following main stages for external antioxidants received with food: the interaction with food substrates, the interaction with the components of digestive secrets, the interaction with components of the blood serum. The investigation of freeradicals processes on these stages demands an adequate comparing method of the obtained results. Presently there are a lot of methods for measuring of antioxidant activity. In our work we used a modified method of luminoldependend chemiluminescence. The scaler of photons was designed in the department of the moleculas photonics of SPhTI and the firm “Real”. The phytium fraction was used as the donors of the sum of free radicals, and DPPH, which was a donor of the superoxyd anion, forming near 2% from the sum of free radicals, emanated from phytium fraction. Some food additives, samples of some alcohol liquids were investigated. The groups of substances with high and low initial level of antioxidant activity were obtained. It was revealed that these groups were interacting with the components of adherent mucous layer and blood serum modifying the level of their unenzymatic antiradical activity. It was found out that the quantity of bioradicals in these substances is not determined only be oxygen radicals.
An analysis of a noise reduction neural network (2003)

An analysis of the four-layer, feedforward, noise-reduction neural network proposed by S. Tamura author and A. Waibel (Int. Conf. Acoust., Speech and Signal Proc., p.553-6, 1988) is described. Each layer has 60 units and is fully interconnected with the next higher layer. The input of the network is given by a 60-point-long (at 12-kHz sampling rate) noisy waveform, and the output is a 60-point-long noise-free waveform. The network was trained using the back-propagation learning algorithm. The network is divided into three subelements for the analysis. Each element stands for a transformation from a layer output to the next higher layer output. First, the transformation from the input layer to the first hidden layer is analyzed, showing that the linear part of the transformation performs linear noise reduction as well as linear speech/noise-characteristic extraction. It is also shown that the transformation from the first hidden layer to the second hidden layer greatly compresses the noise region of the first hidden layer by sigmoid nonlinearities, while preserving its speech region, and the transformation from the second hidden layer to the output layer linearly suppresses the noise components. The spectra of basis vectors spanning an output waveform space show poor higher formant structures.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Production of 3D Structures in Printing (2014)

The ability to form a raised three dimensional image makes possible the use of modified processes, inks and substrates in fine art work, such as children’s books, business cards, postcards, and special type printing processes. If the raised image attains the required height and firmness, it can be used in printing of Braille characters. Production of three dimensional (3D) images on a substrate can be accomplished by old fashioned embossing procedures, a process using hectographic or spirit duplicating masters, or raised Xerographic printing with thermally intumesced electroscopic powders. It may also be done employing three-dimensional imaging paper with randomly distributed fibers with uniformly dispersed unexpanded synthetic thermoplastic polymeric microspheres, thermographic processes, special printing processes, which work by building parts of light curable photo-polymer in layers, or heat transfer printing with thermally-expandable ink layer. Results from our laboratory show a modified formula of hot melt ink that can be used in 3D thermal wax printing process to create raised images on the substrates. An extensive study of thermal behavior of the components of proposed phase change ink has been carried out.
<title>Organic storage media for holographic optical memory: state-of-the-art and future</title> (2000)

At present the main application of holography is the development of holographic optical memory with the super high information capacity. Recent advantages in decision of a number of technical problems associated with making holographic optical devices brought to the fore the question of the development of light-sensitive media of different types (photopolymerizable compositions, dichromated gelatin layers, photorefractive and photoanisotropic materials, etc.) It was shown that there are perspectives of the development of polymerizable materials based on photobleaching photochromogenic and photochromic photo- initiators for archive optical memory with the same information capacity is associated with expected advances in making photoanisotropic polymers containing photochromic fragments.
New entrants take SA on a cheese adventure : dairy (2012)

South African tastes have matured from bright orange, processed cheeses to products that are far more adventurous and exciting, and the industry is responding with new innovations.
[Is there a preference among fibrin glues for nerve anastomosis?]. (1989)

Although fibrin glues have been successful in many areas of surgery, they have not become fully established in nerve anastomosis, even in ENT surgery, an area where significant advantages were expected. As the fibrin clot dissolves prematurely, and dehiscences follow, antifibrinolytic substances must be added to the adhesive. Fibrosis often complicates the use of nerve adhesives. We examined both adhesive systems for their ability to induce fibrosis and their regenerative success rate. Using 1000 KIU aprotinin and 4 IU thrombin there was no significant difference on the effect of both commercially available fibrin adhesives on the collagen content of a nerve anastomosis or on the cumulative action potential in the rat. The proportion of connective tissue was about 33%. Regeneration was undoubtedly recorded.
Successful Pregnancy Outcome in Women With Bad Obstetric History and Recurrent Fetal Loss Due to Thrombophilia: Effect of Unfractionated Heparin and Low—Molecular Weight Heparin (2007)

Acquired and inherited thrombophilias are known to be associated with unfavorable pregnancy outcome including recurrent fetal loss. There are differences of opinion whether these patients need to be treated with aspirin, unfractionated heparin, low-molecular weight heparin, corticosteroids, or intravenous immunoglobulins. In all, 25 consecutive patients with a history of fetal loss and 7 patients who presented in early pregnancy with deep-vein thrombosis were treated, and their pregnancy outcome was noted. All the women were positive either for a solitary or for a combination of acquired and heritable thrombophilia markers. In all, 23 patients were treated with unfractionated heparin and 9 with low-molecular weight heparin. In all, 16 out of 23 patients (69.6%) treated with unfractionated heparin and 9 out of 9 (100%) treated with low-molecular weight heparin had successful pregnancy outcome. There was a complete resolution of thrombus in all the cases. None of the patients had any adverse reactions such as heparin-induced thrombocytopenia, thrombosis, or fracture. Both unfractionated heparin and low-molecular weight heparin were effective in cases of bad obstetric history and recurrent pregnancy loss due to thrombophilia. However, low-molecular weight heparin was found to be more effective than unfractionated heparin along with other advantages of not requiring laboratory monitoring and easy administration. None of the patients in either group had to interrupt the therapy for any adverse treatment-related complications.
Kinetics of Hyperplasia in Psoriasis (1963)

Adequate biologic definition of certain disease processes and the morphogenesis of lesions would seem to hold the advantage of giving a kind of understanding on which to base further explorations into the disease under concern. To date there seems to be general agreement that the epidermal lesion of psoriasis can be categorized by hyperplasia and increased mitotic activity of the epidermis. This limited definition does not specifically identify psoriasis, for it is also applicable to a number of unrelated epidermal lesions on which there is also but casual information. This study attempts to characterize the hyperplasia of the epidermis in psoriasis, and to outline the kinetics of some of the changes in the tissues and cell populations involved. Materials and Methods For the analyses described below, biopsy specimens of psoriasis lesions were obtained from the upper back of six patients (four men, two women) with psoriasis vulgaris; from four of
Single phage T4 DNA packaging motors exhibit large force generation, high velocity, and dynamic variability (2007)

Terminase enzyme complexes, which facilitate ATP-driven DNA packaging in phages and in many eukaryotic viruses, constitute a wide and potentially diverse family of molecular motors about which little dynamic or mechanistic information is available. Here we report optical tweezers measurements of single DNA molecule packaging dynamics in phage T4, a large, tailed Escherichia coli virus that is an important model system in molecular biology. We show that a complex is formed between the empty prohead and the large terminase protein (gp17) that can capture and begin packaging a target DNA molecule within a few seconds, thus demonstrating a distinct viral assembly pathway. The motor generates forces >60 pN, similar to those measured with phage phi29, suggesting that high force generation is a common property of viral DNA packaging motors. However, the DNA translocation rate for T4 was strikingly higher than that for phi29, averaging approximately 700 bp/s and ranging up to approximately 2,000 bp/s, consistent with packaging by phage T4 of an enormous, 171-kb genome in <10 min during viral infection and implying high ATP turnover rates of >300 s(-1). The motor velocity decreased with applied load but averaged 320 bp/s at 45 pN, indicating very high power generation. Interestingly, the motor also exhibited large dynamic changes in velocity, suggesting that it can assume multiple active conformational states gearing different translocation rates. This capability, in addition to the reversible pausing and slipping capabilities that were observed, may allow phage T4 to coordinate DNA packaging with other ongoing processes, including viral DNA transcription, recombination, and repair.
Natural Killer and B-Lymphoid Potential in CD34+ Cells Derived From Embryonic Stem Cells Differentiated in the Presence of Vascular Endothelial Growth Factor (1998)

Differentiation of totipotent mouse embryonic stem (ES) cells to various lymphohematopoietic cells is an in vitro model of the hematopoietic cell development during embryogenesis. To understand this process at cellular levels, differentiation intermediates were investigated. ES cells generated progeny expressing CD34, which was significantly enhanced by vascular endothelial growth factor (VEGF). The isolated CD34+ cells were enriched for myeloid colony-forming cells but not significantly for erythroid colony-forming cells. When cultured on OP9 stroma cells in the presence of interleukin-2 and interleukin-7, the CD34+ cells developed two types of B220+ CD34- lymphocytes: CD3- cytotoxic lymphocytes and CD19+ pre-B cells, and such lymphoid potential was highly enriched in the CD34+ population. Interestingly, the cytotoxic cells expressed the natural killer (NK) cell markers, such as NKR-P1, perforin, and granzymes, classified into two types, one of which showed target specificity of NK cells. Thus, ES cells have potential to generate NK-type cytotoxic lymphocytes in vitro in addition to erythro-myeloid cells and pre-B cells, and both myeloid and lymphoid cells seem to be derived from the CD34+ intermediate, on which VEGF may play an important role.
Biological Activities of Synthetic Peptides Corresponding to Fragments of and to the Entire Sequence of the Vasoactive Intestinal Peptide (1973)

An octacosapeptide with the entire sequence proposed for the newly isolated vasoactive intestinal polypeptide was synthesized and had the expected biological properties. Synthetic peptides corresponding to the C-terminal hendeca-, tetradeca-, pentadeca-, and docosapeptide sequences of the vasoactive intestinal polypeptide showed activities that increased with increasing chain length.
Equation-of-State Modeling for Reservoir-Fluid Samples Contaminated by Oil-Based Drilling Mud Using Contaminated-Fluid Pressure/Volume/Temperature Data (2012)

Summary Bottomhole samples collected in wellbore systems using oil-based muds (OBMs) are likely to be contaminated by medium-to-heavy hydrocarbon fractions present in the OBM. Pressure/volume/ temperature (PVT) data measured for a contaminated fluid will not be representative for the clean reservoir fluid, and such PVT data are hence often ignored by the operator, which means loss of a considerable investment. A proper estimate of the representative clean reservoir fluid is essential for reserves estimation and facilities design. Unfortunately, no experimental methods exist for such estimations. It would be valuable for the oil industry to have options for numerical cleaning of OBM-contaminated reservoir fluids and to be able to carry out equation-of-state (EOS) modeling and regression for a contaminated composition in a way that would allow PVT data for a contaminated fluid to be corrected to represent the uncontaminated fluid. This paper describes such a methodology, which is integrated with EOS modeling procedures for numerically cleaned reservoir-fluid compositions. Thanks to this method, PVT data for contaminated samples do not have to be ignored and oil and gas operators can justify investing in PVT analyses for contaminated-fluid samples. This paper details the process through which the available data can be used. The composition of the reservoir fluid is estimated from the composition of the fluid with a certain content of OBM contaminate, and, contrary to other proposed methods for numerical cleaning, it takes into consideration that the aromaticity of the reservoir fluid may deviate substantially from that of the OBM contaminate. A regression procedure is applied afterward using the available PVT data in order to develop ultimately an EOS model for the clean reservoir fluid. Compositional data and PVT data are presented for a real reservoir fluid contaminated with OBM. Because data are also available for the clean reservoir fluid, it has been possible to verify the validity of the suggested procedure. The numerical cleaning procedure does not require any nonstandard laboratory data, and the given method also is not restricted to any particular brand of OBM or well type.
The Operation of Transnational Degree and Diploma Programs (1998)

The development of an export oriented international student program in Australia in the mid 1980 provided the impetus for Australian higher education institutions to take their programs offshore. Now a decade later, 34 of Australia s 38 universities are offering 493 programs offshore to an estimated 20,000 students, predominately under taking Australian qualifications in their own country (AVCC, 1997). This paper discusses the various models that Australian higher education institutions have used to develop these transnational programs (including twinning, moderation, distance mode, joint awards, internet delivery, franchising and campus models), and explores a number of issues in their delivery (including why programs are offered offshore, quality assurance and the rules and regulations of the home country).
Application of the Michaelis–Arbusov reaction to the synthesis of internucleoside 3′-S-phosphorothiolate inkages (1994)

The 5′-O-monomethoxytrityl-3′-S-(aryldisulfanyl)-3′-deoxythymidines 7 and 8 have been prepared by the reaction of 5′-O-monomethoxytrityl-3′-thiothymidine with the appropriate arenesulfenyl chloride. These disulfides undergo a Michaelis–Arbusov reaction with simple trialkyl phosphites to yield 5′-O-monomethoxytrityl-3′-thiothymidin-3′-yl O,O-dialkyl phosphorothiolates. More interestingly, 3′-deoxy-3′-S-(2, 4-dinitrophenylsulfanyl)-5′-O-monomethoxytritylthymidine 8 reacts with a variety of thymidin-5′-yl dialkyl phosphites to give dithymidine phosphorothiolate triesters with the phosphorothiolate group protected with either a methyl or a 2-cyanoethyl group.3′-O-(tert-Butyldimethylsilyl)thymidin-5′-yl triethylammoniumphosphonate 17 is converted into the corresponding bis-(O-trimethylsilyl) phosphite by treatment with bis(trimethylsilyl)trifluoroacetamide. in situ Reaction of this phosphate with disulfide 8 gives, after work-up, the dithymidine phosphorothiolate diester directly. Methylation of compound 17 with methyl chloromethanoate, followed by silylation and subsequent reaction with disulfide 8, gives the methyl-protected dithymidine phosphorothiolate triester.
Mechanisms of antimicrobial activity of calcium hydroxide: a critical review (1999)

Literature review The primary function of calcium hydroxide as a routine intracanal medicament is to provide antimicrobial activity. However, the mechanisms of antimicrobial activity of calcium hydroxide are not well known. Physicochemical properties of this substance may limit its effectiveness in disinfecting the entire root canal system. In addition, calcium hydroxide is not effective against all bacterial species found in root canal infections. Association with other medicaments may enhance the efficacy of the intracanal medication in eliminating residual bacteria in the root canal system.