gebhart/patrepeval huggingface dataset:
TARGET SITE SELECTION IN TRANSPOSITION (1997)

Transposable elements are discrete mobile DNA segments that can insert into nonhomologous target sites. Diverse patterns of target site selectivity are observed: Some elements display considerable target site selectivity and others display little obvious selectivity, although none appears to be truly “random.” A variety of mechanisms for target site selection are used: Some elements use direct interactions between the recombinase and target DNA whereas other elements depend upon interactions with accessory proteins that communicate both with the target DNA and the recombinase. The study of target site selectivity is useful in probing recombination mechanisms, in studying genome structure and function, and also in providing tools for genome manipulation.
Postoperative Analgesia by Intravenous Clonidine (1991)

Clonidine, an alpha 2 adrenoreceptor agonist, has nonopiate antinociceptive properties, which might be an alternative for postoperative analgesia free of opioid-induced side effects. To document the analgesic properties of intravenous clonidine during the postoperative period, 50 ASA physical status 1 patients, immediately after spinal fusion, were randomly assigned to two groups, blindly administered either clonidine (5 micrograms/kg infused the 1st h and then 0.3 microgram-1.kg-1.h-1 during 11 h) or a placebo. A visual analog scale graded from 0 (no pain) to 100 mm was used to assess pain before clonidine or placebo administration (T0), at the end of the loading dose (T1) and then every 2 h (T3, T5, T7, T9, and T11). Morphine (0.1 mg/kg) was administered intramuscularly after each pain measurement if the score was greater than 50 mm. No morphine was given at T0. Hemodynamics, blood gases and plasma clonidine concentrations were measured each time the pain score was measured. The pain score decreased from 42 +/- 5 to 26 +/- 3 mm (mean +/- standard error) in the clonidine group whereas it was unchanged in the placebo group despite a greater morphine requirement (dose for each patient: 3.8 +/- 1 vs. 10.8 +/- 1.2 mg). Clonidine delayed the onset of pain and the first request for morphine injection. Mean arterial pressure decreased to 74 +/- 2 mmHg in the clonidine group (-26 +/- 2 vs. -15 +/- 2% in the placebo group at T11) despite a significant increase in the cumulative fluid volume.(ABSTRACT TRUNCATED AT 250 WORDS)
Template Synthesis and Magnetic Manipulation of Nickel Nanowires (2005)

In this experiment students prepare nickel nanowires using a template synthesis technique and characterize their properties. Electrodeposition of nickel to fill the 200-nm diameter pores of a commercially-available alumina filtration membrane is accomplished using a nickel salt solution and a AA battery. The nanowires, which are ~200 nm in diameter and up to ~50 Î¼m in length, can be liberated from the membrane by dissolving the alumina template with sodium hydroxide. Suspensions of nanowires on a microscope slide can be observed using a common optical microscope. The alignment and movement of the magnetic nanowires can be controlled using magnets. This experiment is appropriate in introductory college chemistry courses and in upper-level physical and inorganic chemistry courses. The experiment provides students with a hands-on laboratory experience in nanotechnology, while illustrating fundamental ideas from a variety of areas, including electrochemistry, magnetism, and materials science.
Netropsin Increases the Linking Number of DNA (1983)

The antibiotic netropsin (Fig. 1) from Streptomyces netropsis shows both antibacterial and antiviral activities (Zimmer 1975). This effect is thought to be a consequence of its high affinity for double-stranded DNA. Many studies have been performed on this interaction, not only because of its clinical importance, but also because examination of its structure shows that it may be a model for protein-nucleic acid interactions. A recent study (Votavova et al. 1981) shows that netropsin- and lysine-containing polypeptides do not, in fact, compete with each other for binding sites on DNA. A wide variety of physicochemical techniques have been used, including circular dichroism (Zimmer and Luck 1970; Luck et al. 1977), sedimentation velocity (Luck et al. 1974), viscosity (Zimmer et al. 1971; Reinert 1972; Luck et al. 1977; Reinert et al. 1979), UV spectroscopy (Zimmer et al. 1971), nuclear magnetic resonance (NMR) (Patel and Canuel 1977; Patel et al. 1981), thermal...
Nonequilibrium Unfolding of Polyelectrolyte Condensates in Electric Fields (2003)

Using simulations and scaling methods, the effect of an electric field on a collapsed polyelectrolyte globule is investigated, where conduction by counterions and the polyelectrolyte itself is taken into account. At a critical field E(*), a nonequilibrium transition occurs at which the polyelectrolyte unfolds and aligns parallel to the external field. E(*) is determined using scaling results for the polarizability of a polyelectrolyte globule and exhibits a dependence on the chain length N, E(*) approximately N(-1/2), which might be useful for electrophoretic separation of charged biopolymers.
Time course of smooth muscle cell proliferation in the intima and media of arteries following experimental angioplasty. (1990)

Smooth muscle cell (SMC) proliferation is known to be an important factor for the development of restenosis after percutaneous transluminal coronary angioplasty. To determine the time course of intimal and medial SMC proliferation and morphological changes after experimental angioplasty, an intimal atheroma was produced with repeated weak electrical stimulations in the right carotid artery of 45 male New Zealand White rabbits. Angioplasty was subsequently performed in 35 rabbits, and the proliferative responses were analyzed with histomorphological and immunohistological criteria at 3, 7, 14, 21, 28, and 42 days after intervention. A hemodynamic relevant stenosis after angioplasty was found in eight (23%) of 35 dilated arteries. In five rabbits the stenosis was due to a mural thrombus, and in three animals restenosis was caused by intimal SMC proliferation. In all dilated arteries the intimal wall thickness increased from 13 +/- 5 intimal cell layers (after electrical stimulation) to 33 +/- 14 cell layers during 28 days after angioplasty (p less than 0.05). Later than 4 weeks after angioplasty, no additional increase of intimal thickening occurred. Application of bromodeoxyuridine 18 and 12 hours before excision of the vessels allowed determination of the percent of cells undergoing DNA synthesis in the intima and media using monoclonal antibody against bromodeoxyuridine. SMCs were identified by alpha-actin staining. Immunohistological quantification of intimal SMC proliferation showed a maximum of cells undergoing DNA synthesis within the first 7 days after angioplasty (p less than 0.01). In contrast, medial proliferation of SMCs was delayed and showed a small but significant increase 21 days after dilatation (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
The tyrosinase related protein-1 (Tyrp1) promoter in transgenic experiments: targeted expression to the retinal pigment epithelium. (1999)

Transgenic experiments targeting gene expression to the retinal pigment epithelium (RPE) require use of a pigment cell-specific promoter. We have chosen 1.4 kb and 4 kb from the promoter of the tyrosinase-related protein 1 gene (Tyrp1) for RPE-specific expression, since Tyrp1 mRNA and protein are detected already at midgestation in this epithelial layer. In eyes of transgenic embryos, expression of the Tyrp1-lacZ fusion construct led to strong and specific expression of beta-galactosidase in the RPE from day E10.5 onwards. The promoter thus proved useful to target expression of two different oncogenes to the RPE, a constitutively active tyrosine kinase receptor (Rfp/Ret) and SV40 T antigen (Tag). Tyrp1-Rfp/Ret transgenic mice developed microphthalmia, primarily induced by changes in the developing RPE. In addition, Tyrp1-Rfp/Ret expression induced proliferation of RPE cells leading to benign RPE tumors in the adult. Tyrp1-Tag transgenic mice developed malignant eye tumors of RPE origin, which invaded the optic nerve and led to metastasis into lymph nodes and spleen.
Computing for rural empowerment: enabled by last-mile telecommunications (2016)

Increasing economic and educational exposure, and promotion of global health and wellness can be achieved through the power of sharing knowledge, technology, and resources. ICT can play a key role in disseminating such knowledge across the world. But a digital divide exists between urban and rural/remote areas, which results in economic and social disparities across regions. Developing last-mile telecommunication technologies for rural/remote areas is a crucial aspect in providing computing and ICT services that can integrate millions of stakeholders in rural/remote areas globally into the digital age, particularly with the advent of cloud computing. This article focuses on the different aspects of providing last-mile rural telecommunication access such as interfering factors, technology options, and deployment trends. This article aims to guide service providers, industry practitioners, and local entrepreneurs with a technology-and-deployment-trend analysis to choose, deploy, and operate suitable telecommunication networks depending on the unique features of the rural/remote area. Our goal is to bring attention to accessible and affordable technologies with practical considerations.
<title>Two factors in visual fatigue caused by stereoscopic HDTV images</title> (2002)

It is said that visual fatigue caused by watching stereoscopic images is due to the conflict between convergence eye movement and accommodation functions. We studied the degree of visual fatigue in subjects watching HDTV stereoscopic images. The HDTV stereoscopic images used as visual stimuli contained only absolute, with no relative, parallax. In the experiments, images were displayed behind or in front of the screen by a 120-Hz time-sequential method. The examination of visual fatigue was carried out with a five-grade subjective evaluation test and measurement of the accommodation response after watching for one hour. We found that when stereoscopic HDTV images were displayed within the corresponding range of depth of focus, and remained static in the depth direction, the degree of visual fatigue was almost the same as that induced by watching images displayed at the depth of the screen. However, when images were displayed outside the corresponding range of depth of focus, visual fatigue was clearly induced. Moreover, we found that even if images were displayed within the corresponding range of depth of focus, visual fatigue was induced if the images were moved in depth according to a step pulse function.
Succinimidyl Carbonates of Polyethylene Glycol (1991)

A new type of functionalized derivatives of polyethylene glycol (PEG), namely succinimidyl carbonates (SC), were prepared and evaluated as reagents for preparation of PEG-protein conjugates. SC-activated PEGs showed high reactivity towards amino groups of lysine residues producing under mild conditions (pH 7.0 - 10.0, 25 °C, 30 min) extensively modified proteins, in which PEG chains are linked to a polypeptide core through stable urethane (carbamate) linkages. A variety of proteins: chymotrypsin, trypsin, adenosine deaminase, asparaginase, arginase, hemoglobin were subjected to modifications with SC-PEG yielding conjugates with excellent preservation of biological/enzymatic activities.
Readback Resolution of Differential Dual CPP Spin Valve Reader (2010)

The readback resolution of conventional CPP spin valve reader is mainly determined by the shield to shield spacing and partially affected by the head media spacing change. As the linear density grows continuously, the bit length will be reduced to sub-10 nm or even sub-5 nm in the future. In such, the shield to shield spacing has to be below 20 nm or even 10 nm. It gradually becomes not feasible to squeeze all the functional layers used by current reader, such as: AFM layer, SAF, tunnel barrier, free layer, and capping layer, in such a small spacing. The differential dual spin valve (DDSV) read head is one of the new reader structures that can provide better readback resolution. This work studied the sensitivity function of DDSV reader without and with shields, then, identified the waveform characteristics of readback signal at different head media spacing (HMS) and gap layer (GL) thickness. The readback resolution of DDSV reader is mainly determined by the thickness of the gap layer between the two free layers. The two shields are still necessary for the DDSV reader in order to have the free layers picking up more localized media flux. The shield to shield spacing at 35 nm helps to constrain the free layers to pick up media flux mainly from ±5 nm region.
Molecular pathogenesis of emphysema (2008)

Emphysema is one manifestation of a group of chronic, obstructive, and frequently progressive destructive lung diseases. Cigarette smoking and air pollution are the main causes of emphysema in humans, and cigarette smoking causes emphysema in rodents. This review examines the concept of a homeostatically active lung structure maintenance program that, when attacked by proteases and oxidants, leads to the loss of alveolar septal cells and airspace enlargement. Inflammatory and noninflammatory mechanisms of disease pathogenesis, as well as the role of the innate and adaptive immune systems, are being explored in genetically altered animals and in exposure models of this disease. These recent scientific advances support a model whereby alveolar destruction resulting from a coalescence of mechanical forces, such as hyperinflation, and more recently recognized cellular and molecular events, including apoptosis, cellular senescence, and failed lung tissue repair, produces the clinically recognized syndrome of emphysema.
Haar wavelet transform with interband prediction and its application to image coding (1995)

Abstract Although the discrete cosine transform (DCT) and wavelet transform have been used as effective techniques for reducing the redundancy of image waveforms, they have the problems of high complexity and causing block distortion. In this paper, a Haar wavelet transform with interband prediction is proposed that permits high‐speed processing and which is suitable for coding as a subband decomposition technique since it generates little block distortion in the decoded images. the interband prediction method of this proposed transform method uses the derivative of the low‐band waveform to predict the high‐band waveform each time a band is split into two sub‐bands. This results in a transform process that gives a prediction residual signal with lower entropy. During the inverse transform, the prediction coefficients obtained from the forward transform are used to predict the high‐frequency waveforms and then, by adding the prediction residual, the original high frequency waveforms are reconstructed. Because the high‐frequency waveforms are generated that smoothly interpolate the up‐sampled, low‐frequency waveforms, any block effects from this prediction technique are difficult to see in the decoded image. A detailed analysis of the proposed interband prediction process is performed by interpreting the proposed transform as a subband decomposition process that is based on the use of a symmetric short‐kernel filter (SSKF) filter bank; then experiments are conducted that demonstrate its performance as a subband decomposition for coding of real image data and the possibility of progressive build‐up of the decoded images. Results show that this transform method is effective for coding image data.
Parathyroid hormone: chemistry and structure-activity relations. (1981)

Peptide synthesis and the application of a wide range of biological assays have permitted intensive and detailed study of structure-activity relations for parathyroid hormone. Within the structure of the hormone molecule reside largely distinct domains critical for receptor binding or activation of adenylate cyclase in addition to receptor binding. Subtle modifications of hormonal structure can cause striking changes in hormone potency or in the nature of the biological properties displayed by such analogs. For parathyroid hormone, structure-activity studies have identified several discrete regions of the molecule that are responsible for independent biological functions. It was determined that these separate functions are displayed in an almost linear fashion along the primary sequence of the hormone--a conceptual framework that has greatly facilitated synthesis of parathyroid hormone analogs. The amino-terminal region of the initially biosynthesized precursor form of parathyroid hormone, pre-proparathyroid hormone, - 31 through - 7, contains a leader or signal sequence. Despite differences in sequence of the parathyroid hormone signal region and other precursor-specific sequences, this region of the molecule possesses biological properties related to intracellular transport and metabolism that appear to be universal for precursor forms of many, if not all, peptide hormones and other secreted proteins. In contrast, the amino-terminal portion of the secreted form of the molecule, sequence region 1-34, has an amino acid sequence that is homologous to that of several peptide hormones, including ACTH, alpha-MSH, beta-MSH, and beta-lipotropin. Yet the biological "message" conveyed by this peptide sequence appears unique to parathyroid hormone. Directions have now been established for the design of hormone inhibitors and for analogs of enhanced biological activity and perhaps even analogs possessing an altered spectrum of biological properties. The rapid advances that are occurring in techniques for peptide synthesis, purification, and analysis; in the variety, sensitivity, and specificity of the increasing number of bioassays; and in the elucidation of peptide and protein conformation may provide further important new directions for analog design. Extension of these investigations of structure and function over the next several years should yield a more sophisticated understanding of the mode of hormone action. In such studies lies the promise of generating highly refined and perhaps clinically useful analogs of parathyroid hormone.
Molecular Characterization of the Lactococcus lactis ptsHI Operon and Analysis of the Regulatory Role of HPr (1999)

The Lactococcus lactis ptsH and ptsI genes, encoding the general proteins of the phosphoenolpyruvate-dependent phosphotransferase system, HPr and enzyme I, respectively, were cloned, and the regulatory role of HPr was studied by mutational analysis of its gene. A promoter sequence was identified upstream of the ptsHI operon, and the transcription start site was mapped by primer extension. The results of Northern analyses showed the presence of two glucose-inducible transcripts, one of 0.3 kb containing ptsH and a second of 2.0 kb containing both ptsH and ptsI. Disruption of the ptsH and ptsI genes in strain NZ9800 resulted in a reduced growth rate at the expense of glucose, but no growth at the expense of sucrose and fructose, confirming the dominant role of the phosphotransferase system in the uptake of these sugars in L. lactis. Complementation of the ptsH and ptsI mutants with the intact genes under the control of a regulated promoter resulted in the restoration of the wild-type phenotype. The role of HPr(Ser-P) in the recently established CcpA-mediated control of galactose metabolism as well as glycolysis was analyzed by producing an HPr mutant carrying an aspartic acid on residue 46 which mimicks a phosphorylated serine. The results of these experiments demonstrated the role of HPr(Ser-P) as corepressor in the catabolite repression of the gal operon. Furthermore, we show for the first time that HPr(Ser-P) functions as a coactivator in the CcpA-mediated catabolite activation of the pyruvate kinase and L-lactate dehydrogenase genes.
Folate Receptor-Targeted Aggregation-Enhanced Near-IR Emitting Silica Nanoprobe for One-Photon in Vivo and Two-Photon ex Vivo Fluorescence Bioimaging (2011)

A two-photon absorbing (2PA) and aggregation-enhanced near-infrared (NIR) emitting pyran derivative, encapsulated in and stabilized by silica nanoparticles (SiNPs), is reported as a nanoprobe for two-photon fluorescence microscopy (2PFM) bioimaging that overcomes the fluorescence quenching associated with high chromophore loading. The new SiNP probe exhibited aggregate-enhanced emission producing nearly twice as strong a signal as the unaggregated dye, a 3-fold increase in two-photon absorption relative to the DFP in solution, and approximately 4-fold increase in photostability. The surface of the nanoparticles was functionalized with a folic acid (FA) derivative for folate-mediated delivery of the nanoprobe for 2PFM bioimaging. Surface modification of SiNPs with the FA derivative was supported by zeta potential variation and (1)H NMR spectral characterization of the SiNPs as a function of surface modification. In vitro studies using HeLa cells expressing a folate receptor (FR) indicated specific cellular uptake of the functionalized nanoparticles. The nanoprobe was demonstrated for FR-targeted one-photon in vivo imaging of HeLa tumor xenograft in mice upon intravenous injection of the probe. The FR-targeting nanoprobe not only exhibited highly selective tumor targeting but also readily extravasated from tumor vessels, penetrated into the tumor parenchyma, and was internalized by the tumor cells. Two-photon fluorescence microscopy bioimaging provided three-dimensional (3D) cellular-level resolution imaging up to 350 μm deep in the HeLa tumor.
The Steady-state Levels of Type I Collagen mRNA Are Reduced in Senescent Fibroblasts (1991)

The decreased collagen content in aging skin could be a consequence of decreased synthesis or increased degradation. The possibility that decreased synthesis of collagen results from decreased synthesis of mRNAs for Type I collagen, the major collagen in skin, was investigated by assessing the steady-state levels of alpha 1(I) and alpha 2(I) collagen mRNAs in actively proliferating and senescent WI-38 fibroblasts. The levels of both alpha 1(I) mRNA and alpha 2(I) mRNA were significantly lower in senescent fibroblasts, suggesting that one factor contributing to the decreased collagen content of aging skin may be decreased synthesis of these collagen mRNAs by senescent fibroblasts. Both mRNAs were reduced to the same extent, suggesting that coordinate regulation of the two Type I collagen genes is maintained in senescent fibroblasts.