gebhart/patrepeval huggingface dataset:
Characterization of concentration gradients of a morphogenetically active retinoid in the chick limb bud. (1987)

It has long been suggested that the generation of biological patterns depends in part on gradients of diffusible substances. In an attempt to bridge the gap between this largely theoretical concept and experimental embryology, we have examined the physiology of diffusion gradients in an actual embryonic field. In particular, we have generated in the chick wing bud concentration gradients of the morphogenetically active retinoid TTNPB, (E)-4-[2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)-1-prope nyl] benzoic acid, a synthetic vitamin A compound. Upon local application of TTNPB the normal 234 digit pattern is duplicated in a way that correlates with the geometry of the underlying TTNPB gradient; low doses of TTNPB lead to a shallow gradient and an additional digit 2, whereas higher doses result in a steep, far-reaching gradient and patterns with additional digits 3 and 4. The experimentally measured TTNPB distribution along the anteroposterior axis, can be modeled by a local source and a dispersed sink. This model correctly predicts the site of specification of digit 2, and provides an empirical estimate of the diffusion coefficient (D) of retinoids in embryonic limb tissue. The numerical value of approximately 10(-7) cm2s-1 for D suggests that retinoids are not freely diffusible in the limb rudiment, but interact with the previously identified cellular retinoic acid binding protein. In addition, D affords an estimate of the time required to establish a diffusion gradient as 3 to 4 h. This time span is in a range compatible with the time scale of pattern specification in developing vertebrate limbs. Our studies support the view that diffusion of morphogenetic substances is a plausible mechanism of pattern formation in secondary embryonic fields.
Difficult lens power calculations (2004)

In difficult cases, standard calculation schemes are overemployed and new mathematical algorithms are necessary to adequately address these problems. Ray-tracing algorithms and other complex mathematical computation schemes are of increasing interest and will more and more replace conventional calculation formulas for determination of intraocular lens power.
Use of spironolactone in dermatology. (2011)

Spironolactone has been used as a potassium-sparing diuretic for more than 30 years. It is a synthetic 17-lactone steroid and primarily acts as an aldosterone antagonist. Since the accidental discovery of its antiandrogenic effects, it has been used in the treatment of many dermatologic conditions in which androgen plays a role in the pathogenesis. Antiandrogenic effects of spironolactone are exerted by reducing testosterone production and inhibiting its action on the target tissues. Spironolactone is used as a primary medical treatment for hirsutism and female pattern hair loss. Continuous treatment is required to sustain the effect. It is an effective alternative treatment for acne in women. It has the benefit of a long-term safety profile. Spironolactone should not be used in pregnancy due to its teratogenic effects and is not used in men due to the risk of feminization.
Generalized K‐space analysis and correction of motion effects in MR imaging (1993)

A new approach to understanding and reducing motion artifacts in magnetic resonance imaging (MRI) is introduced. This paper presents a novel technique for correcting generalized motion artifacts arising from translation, rotation, dilation, and compression, or any combination thereof. We also describe a new pulse sequence and a specialized postprocessing technique required to suppress these motion artifacts. The correction algorithm corrects for generalized motion. The theoretical basis of the correction scheme is founded upon the (k,t)-space formalism and the concept of pulse sequence contrast mapping functions. The proposed (k,t) formalism is based on the Fourier projection slice theorem and allows us to determine how motion artifacts arise. The correction technique currently suffers from some spatial resolution and signal-to-noise ratio limitations, and works better for small objects than large objects. These problems will be investigated in subsequent studies.
Chiral alcohol production by NADH‐dependent phenylacetaldehyde reductase coupled with <i>in situ</i> regeneration of NADH (2002)

Phenylacetaldehyde reductase (PAR) produced by styrene-assimilating Corynebacterium strain ST-10 was used to synthesize chiral alcohols. This enzyme with a broad substrate range reduced various prochiral aromatic ketones and beta-ketoesters to yield optically active secondary alcohols with an enantiomeric purity of more than 98% enantiomeric excess (e.e.). The Escherichia coli recombinant cells which expressed the par gene could efficiently produce important pharmaceutical intermediates; (R)-2-chloro-1-(3-chlorophenyl)ethanol (28 mg.mL-1) from m-chlorophenacyl chloride, ethyl (R)-4-chloro-3-hydroxy butanoate) (28 mg.mL-1) from ethyl 4-chloro-3-oxobutanoate and (S)-N-tert-butoxycarbonyl(Boc)-3-pyrrolidinol from N-Boc-3-pyrrolidinone (51 mg.mL-1), with more than 86% yields. The high yields were due to the fact that PAR could concomitantly reproduce NADH in the presence of 3-7% (v/v) 2-propanol in the reaction mixture. This biocatalytic process provided one of the best asymmetric reductions ever reported.
Spin Hall effect in spin-valley coupled monolayers of transition metal dichalcogenides (2013)

We study both the intrinsic and extrinsic spin Hall effect in spin-valley coupled monolayers of transition metal dichalcogenides. We find that whereas the skew-scattering contribution is suppressed by the large band gap, the side-jump contribution is comparable to the intrinsic one with opposite sign in the presence of scalar and magnetic scattering. Intervalley scattering tends to suppress the side-jump contribution due to the loss of coherence. By tuning the ratio of intra- to intervalley scattering, the spin Hall conductivity shows a sign change in hole-doped samples. The multiband effect in other doping regimes is considered, and it is found that the sign change exists in the heavily hole-doped regime, but not in the electron-doped regime.
Progress in productivity and weld quality in UOE pipes by four-wire submerged arc welding. (1986)

Spurred by the growing demand for heavy wall UOE pipes with excellent toughness, recent progress by the 4-wire submerged arc welding (SAW) method is reported from the aspects of productivity and weld quality. The 4-wire SAW method is found to bring about 10-30% improvement in productivity and to result in a remarkable suppression of slag inclusion under optimized welding conditions, for example, in current pha se and current ratio. It is also confirmed that the speedup by the 4-wire SAW method does not deteriorate weld quality.Special attentions are paid on the weld quality of heavy wall pipes to meet the recent market situation. This was because there are two problems, i.e., the formation of coarse microstructures of low toughness owing to slow cooling rate and the deterioration of external bead appearance. To cope with them, firstly, the control of nitrogen, oxygen and boron contents in weld metal must be conducted. The optimum ratio between nitrogen and boron contents for excellent toughness is found to be B=0.7•[N]±15 (ppm) for [N]≤80ppm. Secondly, a fused type flux is developed, which has excellent performances in both lowering oxygen content in weld metal to 250-300ppm and suppressing the deterioration of bead appearance. Charpy V-notch Energy more than 100J at -60°C has, then been achieved based on above studies.
A Comprehensive Approach (1989)

Toxic Epidermal Necrolysis (TEN) is a life-threatening disorder with reported mortality rates of 25-60 percent in pediatric patients. The authors report on their experience in managing six children using a standardized treatment protocol in the intensive care unit of a regional burn center. Areas of sloughed skin were covered with porcine xenograft (pig skin) until reepithelialization was complete. There was one death in the series, and one child had ophthalmologic complications. Treatment in a multidisciplinary burn center is recommended for children with TEN.
Molecular mechanisms of cardiac gene expression (1993)

Although the physiological properties of the myocardium and their dynamic character have been the focus of intense research during the past three decades, the biochemical and molecular correlates underlying cardiac development and performance have, until recently, remained poorly understood. The development of modern cellular and molecular biology has provided the necessary tools to undertake the study of the mechanisms involved in cardiac development and to understand the basis for important clinical and experimental problems in cardiovascular physiology. Most of the gene encoding contractile proteins have been cloned and characterized. The availability of molecular probes and the ability to introduce genes into individual cell types and tissues of living animals, are the most important breakthroughs of molecular and cell biology. This permits not only to analyze basic mechanisms of gene expression but has also significant practical applications for gene therapy. It is now possible to analyze the role of different regulatory gene sequences and identify their corresponding trans-active factors. In addition, direct gene injection makes it possible to study gene expression in a natural context, under conditions that are physiologically relevant and controllable.
Site-directed mutations in fungal laccase: effect on redox potential, activity and pH profile (1998)

A Myceliophthora thermophila laccase and a Rhizoctonia solani laccase were mutated on a pentapeptide segment believed to be near the type-1 Cu site. The mutation L513F in Myceliophthora laccase and the mutation L470F in Rhizoctonia laccase took place at a position corresponding to the type-1 Cu axial methionine (M517) ligand in Zucchini ascorbate oxidase. The triple mutations V509L,S510E,G511A in Myceliophthora laccase and L466V,E467S,A468G in Rhizoctonia laccase involved a sequence segment whose homologue in ascorbate oxidase is flanked by the M517 and a type-1 Cu-ligating histidine (H512). The single mutation did not yield significant changes in the enzymic properties (including any significant increase in the redox potential of the type-1 Cu). In contrast, the triple mutation resulted in several significant changes. In comparison with the wild type, the Rhizoctonia and Myceliophthora laccase triple mutants had a phenol-oxidase activity whose pH optimum shifted 1 unit lower and higher, respectively. Although the redox potentials were not significantly altered, the Km, kcat and fluoride inhibition of the laccases were greatly changed by the mutations. The observed effects are interpreted as possible mutation-induced structural perturbations on the molecular recognition between the reducing substrate and laccase and on the electron transfer from the substrate to the type-1 Cu centre.
Microelectromechanical diffraction gratings: Areas of applicability and prospects (2013)

The structure and specific features of operation of microelectromechanical systems, micromirror devices, and diffraction gratings controlled by an electric field are considered. Elements of microelectromechanical diffraction gratings and some applied problems solved with the use of these gratings are described. A new element of the microelectromechanical diffraction grating based on using dielectric materials with a high dielectric permeability in the gap between the electrodes is proposed. As compared with available analogs, this element has a lower control voltage, a higher clock frequency, and better processability. The characteristics of the new element and available analogs are compared.
Influence of Gonadal Steroids on Age- and Sex-Related Secretory Patterns of Growth Hormone in the Rat<sup>*</sup> (1984)

The influence of sex steroids on the pulsatile GH-secretory pattern was investigated in male and female rats of different ages. Neonatal and prepubertal gonadectomy was performed when the rats were 0-1 and 25 days old, respectively. Determinations of plasma GH levels were made in blood samples obtained from the tip of the tail or from a chronic intracardiac venous cannula. After blood sampling from the tip of the tail, maximum and minimum plasma GH levels were determined in individual rats in order to evaluate pulse height and baseline plasma GH levels. In the chronically cannulated rats the GH pulse height and plasma GH baseline levels in individual rats were determined by means of a pulse analysis computer program. Neonatal gonadectomy of male and female rats did not affect the increase in plasma GH that is observed during late prepubertal life in both sexes. However, the pulsatile, sexually differentiated, secretory pattern of GH seen in sexually mature male and female rats was modulated by gonadectomy. In adult male rats, GH was secreted in regular episodes at 3- to 4-h intervals, baseline levels being low or undetectable. After neonatal or prepubertal gonadectomy, GH baseline levels increased in comparison to the sham-operated controls. Replacement therapy with testosterone completely reversed this effect, indicating that a continuous presence of testosterone is necessary for maintaining the low baseline GH levels in adult male rats. Neonatal, but not prepubertal, gonadectomy decreased GH pulse height in male rats during adult life, suggesting that neonatal androgen secretion is a determinant for the pulse height in adult male rats. In female rats, GH pulse height was lower and baseline levels were higher than in male rats. Neonatal gonadectomy resulted in higher plasma GH pulses during puberty and decreased GH baseline levels postpubertally. There were no apparent differences in the GH-secretory patterns between male and female rats after neonatal gonadectomy. Neonatal gonadectomy of male rats decreased body weight gain as well as longitudinal bone growth, as measured in the proximal tibia by the tetracycline method. In contrast, neonatal gonadectomy of female rats resulted in a stimulation of body weight gain and longitudinal bone growth. The present results demonstrate that gonadal steroids influence GH secretion in the rat. We suggest that the sexual differentiation of the GH secretory pattern may be important for the difference in body growth between male and female rats.
<i>In vitro</i> characterization of a plastid terminal oxidase (PTOX) (2003)

The plastid terminal oxidase (PTOX) encoded by the Arabidopsis IMMUTANS gene was expressed in Escherichia coli cells and its quinone/oxygen oxidoreductase activity monitored in isolated bacterial membranes using NADH as an electron donor. Specificity for plastoquinone was observed. Neither ubiquinone, duroquinone, phylloquinone nor benzoquinone could substitute for plastoquinone in this assay. However, duroquinol (fully reduced chemically) was an accepted substrate. Iron is also required and cannot be substituted by Cu(2+), Zn(2+) or Mn(2+). This plastoquinol oxidase activity is independent of temperature over the 15-40 degrees C range but increases with pH (from 5.5 to 9.0). Unlike higher plant mitochondrial alternative oxidases, to which PTOX shows sequence similarity (but also differences, especially in a putative quinone binding site and in cysteine conservation), PTOX activity does not appear to be regulated by pyruvate or any other tested sugar, nor by AMP. Its activity decreases, however, with increasing salt (NaCl or KCl) concentration. Various quinone analogues were tested for their inhibitory activity on PTOX. Pyrogallol analogues were found to be inhibitors, especially octyl gallate (I50 = 0.4 microM ) that appears far more potent than propyl gallate or gallic acid. Thus, octyl gallate is a useful inhibitor for future in vivo or in organello studies aimed at studying the roles of PTOX in chlororespiration and as a cofactor for carotenoid biosynthesis.
IgM-enriched human intravenous immunoglobulin suppresses T lymphocyte functions<i>in vitro</i>and delays the activation of T lymphocytes in hu-SCID mice (2006)

Previous studies of an experimental human immunoglobulin preparation for intravenous use, containing normal pooled IgM (IVIgM), have shown its beneficial therapeutic effect in experimental autoimmune diseases. The mechanisms of its immunomodulatory activity remain however, poorly understood. In the experiments reported here, IVIgM inhibited the proliferation of various autonomously growing human lymphoid cell lines in vitro, as well as of MLR- and of PHA-stimulated human T-lymphocytes. These effects of IVIgM were observed at non-apoptotic concentrations and were stronger on a molar basis than those of normal pooled IgG for intravenous use (IVIg). Both preparations, when administered to SCID mice, repopulated with human peripheral blood mononuclear cells, delayed the expression of the early activation marker CD69 on both human CD4+ and CD8+ T-lymphocytes, activated by the mouse antigenic environment. The data obtained show that normal pooled human IgM exerts a powerful antiproliferative effect on T-cells that is qualitatively similar but quantitatively superior to that of therapeutic IVIg. Our results suggest that infusions with IVIgM might have a significant beneficial immunomodulating activity in patients with selected autoimmune diseases.
4D Crop Monitoring: Spatio-Temporal Reconstruction for Agriculture (2016)

Autonomous crop monitoring at high spatial and temporal resolution is a critical problem in precision agriculture. While Structure from Motion and Multi-View Stereo algorithms can finely reconstruct the 3D structure of a field with low-cost image sensors, these algorithms fail to capture the dynamic nature of continuously growing crops. In this paper we propose a 4D reconstruction approach to crop monitoring, which employs a spatio-temporal model of dynamic scenes that is useful for precision agriculture applications. Additionally, we provide a robust data association algorithm to address the problem of large appearance changes due to scenes being viewed from different angles at different points in time, which is critical to achieving 4D reconstruction. Finally, we collected a high quality dataset with ground truth statistics to evaluate the performance of our method. We demonstrate that our 4D reconstruction approach provides models that are qualitatively correct with respect to visual appearance and quantitatively accurate when measured against the ground truth geometric properties of the monitored crops.
A review of shampoo surfactant technology: consumer benefits, raw materials and recent developments (2017)

Surfactants form the core of all shampoo formulations, and contribute to a wide range of different benefits, including cleansing, foaming, rheology control, skin mildness and the deposition of benefit agents to the hair and scalp. The purpose of this review was to assist the design of effective, modern, shampoo surfactant technologies. The mechanisms through which surfactants help deliver their effects are presented, along with the appraisal techniques through which surfactant options can be tested and screened for product development. The steps that should be taken to select the most appropriate blend of surfactants are described, and useful information on the most widely used surfactants is provided. The review concludes with an examination of recent developments in 'greener' surfactants, 'sulphate-free' technologies and structured liquid phases for novel sensory properties and for suspending benefit agents.
Model for strain and magnetization in magnetic shape-memory alloys (1998)

The large magnetic-field-induced strains observed in martensitic phases based on Ni2MnGa and in other magnetic shape memory alloys are believed to arise from a process of twin-boundary motion rather than magnetostriction. The dependence of strain on magnetization, e(M), generally shows a large component that is linear (rather than quadratic) in M below saturation (quadratic dependence being typical of magnetostrictive strain). A simple phenomenological model for the magnetization process and field-induced strain by twin-boundary and phase-boundary motion is proposed for both the strong and weak anisotropy cases. The model is shown to account for the nearly linear dependence of strain on magnetization in the martensitic phases of these materials. It shows the field dependence of the magnetization and strain to be functions of an effective stiffness constant, C, the transformation strain, e0, and the magnetic anisotropy of the martensitic phase, Ku, through two reduced field parameters, he=MsH/Ce02 and ha=MsH/2Ku. The model also accounts for the magnetization remanence and the nonlinear field dependence closer to saturation (which produces little strain). The curvature observed in e(H) at very low fields is not described by this two-variant model and may be related to the fact that more variants exist which respond to the field with a distribution of susceptibilities.
Comparing Apples and Oranges (2019)

Asking pairwise comparison questions is common. Yet, we often find ourselves comparing apples and oranges --- the two entities of interest are not readily comparable. To understand how technologies can extend our capabilities to conduct pairwise comparisons during data analysis, we analyzed pairwise comparison questions collected from crowd workers and propose a taxonomy of pairwise comparisons. We demonstrate how the taxonomy can be adopted by incorporating pairwise comparison capabilities into Duo, a spreadsheet application that supports comparing two groups of records in a data table. Duo decomposes a pairwise comparison question into rules and showcases sloppy rules, a query technique for specifying pairwise comparisons. We conducted a user study comparing sloppy rules and natural language. The findings suggest that for easier pairwise comparison tasks, the two techniques are comparable in efficiency and preference and that for more difficult pairwise comparison tasks, sloppy rules allow faster specification and are more preferable.
Polycaprolactone–poly(ethylene glycol) block copolymer, I: synthesis and degradability <i>in vitro</i> (1993)

Abstract A new type of biodegradable polymer material, poly(caprolactone)–poly(ethylene glycol) block copolymer (PCL‐b‐PEG), was synthesized by means of direct copolycondensation of ε‐caprolactone with poly(ethylene glycol) in the presence of a Ti(OBu) 4 catalyst. The degradability of the polycaprolactone was improved by introducing a PEG component into it. The degradation of PCL‐b‐PEG copolymer increase with a decreasing crystallinity of the copolymer, and can be controlled by adjusting the component ratio of the copolymer.
Vapor-Condensation-Assisted Optical Microscopy for Ultralong Carbon Nanotubes and Other Nanostructures (2014)

Here we present a simple yet powerful approach for the imaging of nanostructures under an optical microscope with the help of vapor condensation on their surfaces. Supersaturated water vapor will first form a nanometer-sized water droplet on the condensation nuclei on the surface of nanostructures, and then the water droplet will grow bigger and scatter more light to make the outline of the nanostructure be visible under dark-field optical microscope. This vapor-condensation-assisted (VCA) optical microscopy is applicable to a variety of nanostructures from ultralong carbon nanotubes to functional groups, generating images with contrast coming from the difference in density of the condensation sites, and does not induce any impurities to the specimens. Moreover, this low-cost and efficient technique can be conveniently integrated with other facilities, such as Raman spectroscope and so forth, which will pave the way for widespread applications.