gebhart/patrepeval huggingface dataset:
Velocity observations above a rippled bed using laser Doppler velocimetry (1992)

Velocity observations are reported in a plane across a regular nonmigrating ripple in 2.5 m of water depth. The forcing was weak, primarily wave‐induced near‐bed orbital motion. The data were acquired using a two‐axis submerged laser Doppler velocimeter. Synchronous records of pressure below the surface were also obtained. The instrumentation is described. The pressure information was used to separate wave‐coherent and turbulence motion in the observed velocity. Turbulent kinetic energy and dissipation rates are obtained over a range of distances above the bed from 1.5 mm above the ripple to 10 cm. Velocity time series are smooth except at high‐velocity magnitudes, indicating the formation of a lee vortex during peak velocities only. The data show convective acceleration of the flow over the ripple and a lack of significant shear in the rms horizontal motion farther from the bed. Velocity spectra at one location, 1.5 mm from the bed show second and third harmonics of the incident wave, which are interpreted to be due to convective acceleration over the ripple and vortex shedding. High‐frequency velocity spectra show uniformly decreasing turbulence intensity away from the bed. We conclude that the boundary layer observed here was transitional, i.e., laminar through small velocity periods, becoming turbulent for short periods during which the breakup of the vortex shed by the ripples occurred. Laminar estimates of maximum bottom friction are consistent with the threshold for initiation of motion criterion for 0.2 mm sand and the observed ripple steepness.
Study of large deformation geomechanical problems with the Material Point Method (2015)

The numerical simulation of real geomechanical problems often entails an high level of complexity; indeed they are often characterized by large deformations, soil-structure interaction and solid-fluid interaction.\nMoreover, the constitutive behavior of soil is highly non-linear.\nLandslides, dam failure, pile installation, and undrground excavation are typical examples of large deformation problems in which the interaction between solid a fluid phase as well as the contact between bodies are essential.\n\nThis thesis addresses the challenging issue of the numerical simulation of large deformation problems in geomechanics.\nThe standard lagrangian finite element methods are not well suited to treat extremely large deformations because of severe difficulties related with mesh distortions.\nThe need to overcome their drawbacks urged researchers to devote considerable effort to the development of more advanced computational techniques such as meshless methods and mesh based particle methods.\n\nIn this study, the Material Point Method (MPM), which is a mesh based particle method, is exploited to simulate large deformation problems in geomechanics.\nThe MPM simulates large displacements with Lagrangian material points (MP) moving through a fixed mesh.\nThe MP discretize the continuum body and carry all the information such as mass, velocity, acceleration, material properties, stress and strains, as well as external loads.\nThe mesh discretizes the domain where the body move through; it is used to solve the equations of motion, but it does not store any permanent information.\n\nIn undrained and drained conditions the presence of water can be simulated in a simplified way using the one-phase formulation.\nHowever, in many cases the relative movement of the water respect to the soil skeleton must be taken into account, thus requiring the use of the two-phase formulation.\n\nThe contact between bodies is simulated with an algorithm specifically developed for the MPM at the beginning of the century.\nThis algorithm was originally formulated for the frictional contact. It extension to the adhesive contact is considered in this thesis, which is well suited to simulate soil-structure interaction in case of cohesive materials.\n\nIn this thesis typical geomechanical problems such as the collapse of a submerged slope and the simulation of cone penetration testing are considered.\nNumerical results are successfully compared with experimental data thus confirming the capability of the MPM to simulate complex phenomena. \n
Hollow Structured Micro/Nano MoS<sub>2</sub> Spheres for High Electrocatalytic Activity Hydrogen Evolution Reaction (2016)

Molybdenum disulfide (MoS2) has attracted extensive attention as a non-noble metal electrocatalyst for hydrogen evolution reaction (HER). Controlling the skeleton structure at the nanoscale is paramount to increase the number of active sites at the surface. However, hydrothermal synthesis favors the presence of the basal plane, limiting the efficiency of catalytic reaction. In this work, perfect hollow MoS2 microspheres capped by hollow MoS2 nanospheres (hH-MoS2) were obtained for the first time, which creates an opportunity for improving the HER electrocatalytic performance. Benefiting from the controllable hollow skeleton structure and large exposed edge sites, high-efficiency HER activity was obtained for stacked MoS2 thin shells with a mild degree of disorder, proving the presence of rich active sites and the validity of the combined structure. In general, the obtained hollow micro/nano MoS2 nanomaterial exhibits optimized electrocatalytic activity for HER with onset overpotential as low as 112 mV, low Tafel slope of 74 mV decade(-1), high current density of 10 mA cm(-2) at η = 214 mV, and high TOF of 0.11 H2 s(-1) per active site at η = 200 mV.
Silicon carbide nozzle for producing molecular beams (2006)

A resistively heated nozzle of silicon carbide (SiC) ceramic was developed for the production of high speed molecular beams for space environment simulation. The nozzle is able to withstand temperatures in excess of 1800°C and pressures to 30bars. In a seeded beam of 1% argon in 99% hydrogen, a speed of 3.9km∕s was achieved for the argon component at a nozzle temperature of 1150°C and a pressure of 23bars.
Investigating the Influence of Interfacial Contact Properties on Open Circuit Voltages in Organic Photovoltaic Performance: Work Function Versus Selectivity (2013)

Abstract The role of work function and thermodynamic selectivity of hole collecting contacts on the origin of open circuit voltage (V OC ) in bulk heterojunction organic photovoltaics is examined for poly(N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole) (PCDTBT) and [6,6]‐phenyl‐C 71 butyric acid methyl ester (PC 71 BM) solar cells. In the absence of a charge selective, electron blocking contact, systematic variation of the work function of the contact directly dictates the V OC , as defined by the energetic separation between the relative Fermi levels for holes and electrons, with little change in the observed dark saturation current, J 0 . Improving the charge selectivity of the contact through an increased barrier to electron injection from the fullerene in the blend into the hole contact results in a decreased reverse saturation current (decreased J 0 and increased shunt resistance, R SH ) and improved V OC . Based on these observations, we provide a set of contact design criteria for tuning the V OC in bulk heterojunction organic photovoltaics.
The Local Injection of Peritoneal Macrophages Induces Neovascularization in Rat Ischemic Hind Limb Muscles (2008)

Macrophages play a pivotal role in the development of newly formed vascular networks, in addition to their normal immunological functions. This research focuses on peritoneal macrophages as a novel source in cell implantation therapy for ischemic diseases. In this study, production of angiogenic growth factors by peritoneal macrophages and its in vivo effect of neovascularization were evaluated. Mononuclear cells from the peritoneal cavity (P-MNCs) enriched with macrophages were isolated and stimulated with hypoxia and interleukin-1beta (IL-1beta) to mimic an ischemic tissue environment in vitro. Expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) of mRNA in P-MNCs was apparently enhanced by hypoxic stimulation, and the production of VEGF protein was also augmented by hypoxia and IL-1beta. A rat ischemic hind limb model was created and P-MNCs (8 x 10(6)/limb) were injected into the ischemic muscles. The blood flow, which was assessed using the colored microsphere method, showed that the percentage blood flow was significantly increased by P-MNCs injection 4 weeks after surgery (48.3 +/- 16.8% in noninjected ischemic limb vs. 84.3 +/- 13.0% in the P-MNCs-injected limb). A histological analysis revealed that the number of capillaries detected by alkaline phosphatase staining was increased in the P-MNCs group 4 weeks after injection. Furthermore, the number of alpha-smooth muscle actin-positive vessels also showed a significant increase following P-MNC injection. The injected P-MNCs labeled with fluorescence were detected in the interstitial space of ischemic muscles, and VEGF protein expression of the implanted cells was confirmed by immunohistochemistry. These results indicate that peritoneal macrophages stimulate capillary formation and arteriogenesis in the ischemic limbs, possibly through the production of angiogenic growth factors. These findings suggest that the physiological angiogenic property of peritoneal macrophages could therefore be utilized for neovascularization in cell implantation therapy.
Comparative organization of nitrogen fixation-specific genes from Azotobacter vinelandii and Klebsiella pneumoniae: DNA sequence of the nifUSV genes (1987)

In the facultative anaerobe Klebsiella pneumoniae 17 nitrogen fixation-specific genes (nif genes) have been identified. Homologs to 12 of these genes have now been isolated from the aerobic diazotroph Azotobacter vinelandii. Comparative studies have indicated that these diverse microorganisms share striking similarities in the genetic organization of their nif genes and in the primary structure of their individual nif gene products. In this study the complete nucleotide sequence of the nifUSV gene clusters from both K. pneumoniae and A. vinelandii were determined. These genes are identically organized on their respective genomes, and the individual genes and their products exhibit a high degree of interspecies sequence homology.
Synthesis and Biological Activity of N4-Methyl-5-azacytidines (1998)

Protected N 4 -methyl and N 4 , N 4 -dimethyl derivatives of 5-azacytidine 3 and 4 were prepared by selective aminolysis of benzoylated 4-methoxy-1-(β-D-ribofuranosyl)-1,3,5-triazin-2(1 H )-one 5 , by glycosylation of silylated N 4 -methyl- or N 4 , N 4 -dimethyl-5-azacytosines 7 and 8 with 2,3,5-tri- O -benzoyl-α,β-D-ribofuranosyl chloride ( 11 ) or by several modifications of the isocyanate method. By the isocyanate approach, also the α-D anomer of protected N 4 -methyl-5-azacytidine 17 was obtained as a minor product. The protected dimethyl derivative 4 was also obtained by the reaction of isobiuret 22 with dimethylformamide dimethyl acetal. The free nucleosides 1 and 2 were obtained either by aminolysis of the free methoxy nucleoside 23 with methylamine or dimethylamine, respectively, or by methanolysis or ammonolysis of the corresponding benzoyl derivatives 3 and 4 . The free α-D anomer 24 was obtained by methanolysis of its tribenzoate 17 . Nucleosides 1 and 2 exhibited a lower antibacterial, antitumor and antiviral activity than the unsubstituted 5-azacytidine.
Synthesis and Characterization of Insulin-like Growth Factor (IGF)-1 Photoprobes Selective for the IGF-binding Proteins (IGFBPs) (2001)

Elevated insulin-like growth factor (IGF)-1 levels are prognostic for the development of prostate and breast cancers and exacerbate the complications of diabetes. In each case, perturbation of the balance between IGF-1/2, the IGF-1 receptor, and the IGF-binding proteins (IGFBPs) leads to elevated IGF-1 sensitivity. Blockade of IGF action in these diseases would be clinically significant. Unfortunately, effective IGF antagonists are currently unavailable. The IGFBPs exhibit high affinity and specificity for the IGFs and serve as natural IGF antagonists, limiting their mitogenic/anti-apoptotic effects. As an initial step in designing IGFBP-based agents that antagonize IGF action, we have begun to analyze the structure of the IGF-binding site on IGFBP-2. To this end, two IGF-1 photoprobes, N(alphaGly1)-(4-azidobenzoyl)-IGF-1 (abG(1)IGF-1) and N(alphaGly1)-([2-6-(biotinamido)-2(p-azidobenzamido)hexanoamido]ethyl-1,3'-dithiopropionoyl)-IGF-1 (bedG(1)IGF-1), selective for the IGFBPs were synthesized by derivatization of the alpha-amino group of Gly(1), known to be part of the IGFBP-binding domain. Mass spectrometric analysis of the reduced, alkylated, and trypsin-digested abG(1)IGF-1.recombinant human IGFBP-2 (rhIGFBP-2) complex indicated photoincorporation near the carboxyl terminus of rhIGFBP-2, between residues 266 and 287. Mass spectrometric analysis of avidin-purified tryptic peptides of the bedG(1)IGF-1.rhIGFBP-2 complex revealed photoincorporation within residues 212-227. Taken together, these data indicate that the IGFBP-binding domain on IGF-1 contacts the distal third of IGFBP-2, providing evidence that the IGF-1-binding domain is located within the C terminus of IGFBP-2.
A Fast Immune Recognition Model based on Immune Response (2014)

This paper proposes a fast immune recognition model based on immune response. Inspired by biological immune system, AIS for anomaly detection has been adopted widely because of its analogy with body resistance in the immune system provided against agents which causes diseases. This paper mainly studies correspondence between immune response and anomaly detection. Compared with traditional AIS, the change of antigen type is judged by statistical techniques, which ignores the differences of the different systems. Antibody recognition is initiated by the proposed model only when the type of antigen has changed, which improves the efficiency of the algorithm. Complexity analysis shows the proposed algorithm is a linear algorithm. The usefulness of the proposed model is demonstrated through experiments. The experiments illustrate the availability and feasibility of the model.
Approximation Technique for Dielectric Loaded Waveguides (1968)

An algebraic procedure is described which yields approximate values for the cutoff frequencies and propagation constants of dielectric-loaded waveguides. The procedure is demonstrated for a waveguide completely filled with an anisotropic dielectric and for waveguides partially filled with isotropic dielectrics. For the latter case results are tabulated for five types of waveguide loading. The symmetrically loaded waveguide is used to show the accuracy which may be expected. This procedure is shown to be identical with the Rayleigh-Ritz variational method but with the advantage that it provides a systematic approach to improve the accuracy and to handle a multitude of waveguide geometries.
Modeling the multicast address allocation problem (2003)

To support IP multicast, domains must assign a unique multicast address to each application from a limited, globally-shared address space. We examine the performance of several classes of address allocation algorithms within the context of the MASC architecture. This study is the first of its kind to model the generalized multicast address allocation problem and consider non-contiguous allocation algorithms. We find that prefix-based allocation outperforms our non-contiguous algorithm, despite the apparent advantages of non-contiguous allocation. We also verify the benefit of using worst-fit for new allocations.
Stages of oocyte development in the zebrafish, <i>Brachydanio rerio</i> (1993)

Oocyte development has been divided into five stages in the zebrafish Brachydanio rerio, based on morphological criteria and on physiological and biochemical events. In stage I (primary growth stage), oocytes reside in nests with other oocytes (Stage IA) and then within a definitive follicle (Stage IB), where they greatly increase in size. In stage II (cortical alveolus stage), oocytes are distinguished by the appearance of variably sized cortical alveoli and the vitelline envelope becomes prominent. In stage III (vitellogenesis), yolk proteins appear in oocytes and yolk bodies with crystalline yolk accrue during this major growth stage. Ooctes develop the capacity to respond in vitro to the steroid 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) by undergoing oocyte maturation. In stage IV (oocyte maturation), oocytes increase slightly in size, become translucent, and their yolk becomes non-crystalline as they undergo final meiotic maturation in vivo (and in response to DHP in vitro). In stage V (mature egg), eggs (approx. 0.75 mm) are ovulated into the ovarian lumen and are capable of fertilization. This staging series lays the foundation for future studies on the cellular processes occurring during oocyte development in zebrafish and should be useful for experimentation that requires an understanding of stage-specific events. © 1993 Wiley-Liss, Inc.
El incremento de la productividad y competitividad en México: Innovación, conocimiento y desarrollo (2013)

espanolEste trabajo tiene como objetivo presentar al lector un estado de conocimiento acerca del concepto de la competitividad, y como esta ha estado asociada cada vez mas a la innovacion, al conocimiento y al desarrollo tecnologico; conceptos que se revisan en este articulo bajo la luz de la investigacion empirica. Se analiza ademas el contexto legal de la innovacion en Mexico, y las acciones concretas que se han de realizar a favor del conocimiento y la innovacion en este pais. EnglishThis paper aims to present the reader a state of knowledge about the concept of competitiveness, and how it has been increasingly associated to innovation, knowledge and technological development; concepts that are reviewed in this article under the light of an empirical research. It also analyzes the legal context of innovation in Mexico and the concrete actions that have been made in favor of innovation and knowledge in this Country.
Automatic segmentation of the facial nerve and chorda tympani in CT images using spatially dependent feature values (2008)

In cochlear implant surgery, an electrode array is permanently implanted in the cochlea to stimulate the auditory nerve and allow deaf people to hear. A minimally invasive surgical technique has recently been proposed-percutaneous cochlear access-in which a single hole is drilled from the skull surface to the cochlea. For the method to be feasible, a safe and effective drilling trajectory must be determined using a preoperative CT. Segmentation of the structures of the ear would improve trajectory planning safety and efficiency and enable the possibility of automated planning. Two important structures of the ear, the facial nerve and the chorda tympani, are difficult to segment with traditional methods because of their size (diameters as small as 1.0 and 0.3 mm, respectively), the lack of contrast with adjacent structures, and large interpatient variations. A multipart, model-based segmentation algorithm is presented in this article that accomplishes automatic segmentation of the facial nerve and chorda tympani. Segmentation results are presented for ten test ears and are compared to manually segmented surfaces. The results show that the maximum error in structure wall localization is approximately 2 voxels for the facial nerve and the chorda, demonstrating that the method the authors propose is robust and accurate.
Returns to Tillage Systems under Changing Input and Output Market Conditions (2009)

Costs and net returns for conventional tillage (CT), reducedtillage (RT) and no-tillage (NT) are evaluated for five cropping systems: continuous soybean, a soybean-grain sorghum rotation, a soybean-wheat rotation, continuous grain sorghum and continuous wheat, over a period of increasing input and output prices, 2006-2008. NT had the highest net return for all of the systems with soybeans each year. NT also had the lowest energy use for all systems. The net returns of NT increased relative to CT and RT from 2006 to 2008 for all of the systems with soybeans. However, this increase in net returns was a result of increasing commodity prices rather than a slower increase in costs for NT.
Three-dimensional Structure of Saccharomyces Invertase (2013)

Invertase is an enzyme that is widely distributed among plants and microorganisms and that catalyzes the hydrolysis of the disaccharide sucrose into glucose and fructose. Despite the important physiological role of Saccharomyces invertase (SInv) and the historical relevance of this enzyme as a model in early biochemical studies, its structure had not yet been solved. We report here the crystal structure of recombinant SInv at 3.3 Å resolution showing that the enzyme folds into the catalytic β-propeller and β-sandwich domains characteristic of GH32 enzymes. However, SInv displays an unusual quaternary structure. Monomers associate in two different kinds of dimers, which are in turn assembled into an octamer, best described as a tetramer of dimers. Dimerization plays a determinant role in substrate specificity because this assembly sets steric constraints that limit the access to the active site of oligosaccharides of more than four units. Comparative analysis of GH32 enzymes showed that formation of the SInv octamer occurs through a β-sheet extension that seems unique to this enzyme. Interaction between dimers is determined by a short amino acid sequence at the beginning of the β-sandwich domain. Our results highlight the role of the non-catalytic domain in fine-tuning substrate specificity and thus supplement our knowledge of the activity of this important family of enzymes. In turn, this gives a deeper insight into the structural features that rule modularity and protein-carbohydrate recognition.
Drug abuse among junior high school students in Norway. (1987)

The use of legal and illegal drugs was screened by a questionnaire of 2,265 junior high school adolescents in a rural and semirural area in Norway. Mental symptoms were independently assessed by a personal interview of a random sample of 177 of the pupils. An index of total environmental adversity was developed based on questionnaire items from family, school and leisure time activities. There was a strong relationship between smoking, the level of alcohol consumption and the use of cannabis and other drugs. Pupils who had used cigarettes, alcohol, cannabis, solutions (sniffing) and tranquillizers, all had higher frequencies of mental symptoms than nonusers. The connection between smoking and mental symptoms was stronger in the females than in the males. Smoking, level of alcohol consumption, cannabis use, sniffing and the use of tranquillizers and other psychotropic drugs were all strongly related to an index of global environmental adversity.
Efficient ipso-nitration of arylboronic acids with iron nitrate as the nitro source (2013)

A novel, simple and efficient ipso-nitration of arylboronic acids with iron nitrate has been developed. The protocol uses readily available arylboronic acids as the starting materials, inexpensive iron nitrate (0.5 equiv.) as the nitro source without addition of an additive, and the corresponding nitroarenes were obtained in good to excellent yields.