gebhart/patrepeval huggingface dataset:
Quality control of ribosomal RNA mediated by polynucleotide phosphorylase and RNase R (2003)

Despite their overall accuracy, errors in macromolecular processes, such as rRNA synthesis and ribosome assembly, inevitably occur. However, whether these errors are remediated and how this might be accomplished is not known. In previous work, we showed that a double mutant strain lacking both polynucleotide phosphorylase (PNPase) and RNase R activities is inviable. In the course of examining the molecular basis for this phenotype, we found that shifting a temperature-sensitive mutant strain to 42 degrees C led to cessation of growth and loss of cell viability. Northern analysis of RNA isolated from such cells after the temperature shift revealed that fragments of 16S and 23S rRNA accumulated to a high level, and that the amount of ribosomes and ribosomal subunits decreased due to defects in ribosome assembly. rRNA fragments were not detected at 31 degrees C or when single mutant strains were grown at 42 degrees C. Pulse-chase analysis showed that the rRNA fragments appeared within 5 min at 42 degrees C, and that they accumulated before the loss of cell viability. The data are consistent with a model in which PNPase and RNase R mediate a previously unknown quality control process that normally removes defective rRNAs as soon as they are generated. In the absence of these RNases, rRNA fragments accumulate, leading to interference with ribosome maturation and ultimately to cell death.
Composites of metal–organic frameworks: Preparation and application in adsorption (2014)

Metal–organic frameworks (MOFs) are one of the most discussed materials of the last decade. Their extraordinary porosity and functionality from metals and organic linkers make them one of the most promising materials for a vast array of applications. The easy tunability of their pore size and shape from the micro- to meso-scale, by changing the connectivity of the inorganic moiety and the nature of the organic linkers, makes these materials special. Moreover, by combining with other suitable materials, the properties of MOFs can be improved further for enhanced functionality/stability, ease of preparation and selectivity of operation. In this review, various methods and paths for the preparation of composites are discussed, especially for those which have been successfully applied to gas and liquid phase adsorptions. In the second part of this paper, several applications in adsorptive processes are discussed.
Invited Article: A test-facility for large-area microchannel plate detector assemblies using a pulsed sub-picosecond laser (2013)

The Large Area Picosecond Photodetector Collaboration is developing large-area fast photodetectors with time resolution </~10 ps and space resolution </~1 mm based on atomic layer deposition-coated glass Micro-Channel Plates (MCPs). We have assembled a facility at Argonne National Laboratory for characterizing the performance of a wide variety of microchannel plate configurations and anode structures in configurations approaching complete detector systems. The facility consists of a pulsed Ti:Sapphire laser with a pulse duration ≈100 fs, an optical system allowing the laser to be scanned in two dimensions, and a computer-controlled data-acquisition system capable of reading out 60 channels of anode signals with a sampling rate of over 10 GS/s. The laser can scan on the surface of a sealed large-area photodetector, or can be introduced into a large vacuum chamber for tests on bare 8 in.-square MCP plates or into a smaller chamber for tests on 33-mm circular substrates. We present the experimental setup, detector calibration, data acquisition, analysis tools, and typical results demonstrating the performance of the test facility.
Characterization of two constitutive forms of rat liver microsomal heme oxygenase. Only one molecular species of the enzyme is inducible. (1986)

The present report describes, for the first time, the identification of two constitutive forms of heme oxygenase, designated as HO-1 and HO-2, in rat liver microsomal fractions. HO-1 was purified to homogeneity and exhibited a specific activity of up to 4000 nmol of bilirubin/mg of protein/h. HO-2 was partially purified to a specific activity of 250 nmol of bilirubin/mg of protein/h. In the native state, the relative activity of HO-2 surpassed that of HO-1 by 2-3-fold. However, a remarkable difference existed in the regulatory mechanism(s) for the production of the two enzyme forms. Whereas the activity of HO-1 was increased up to 100-fold in response to cobalt, cadmium, hematin, phenylhydrazine, and bromobenzene, that of HO-2 was fully refractory to these agents. The two forms differed in their apparent Km, thermolability, ammonium sulfate precipitation, antigenicity, electrophoretic mobility under nondenaturing conditions, and chromatographic behavior. Specifically, for HO-1 the apparent Km value was 0.24 microM, whereas that for HO-2 was 0.67 microM. HO-2 preparation was more susceptible to heat inactivation; nearly 65% activity was retained by HO-1 preparation after exposure to 60 degrees C for 10 min, whereas under the same conditions only about 25% of HO-2 activity was retained. When subjected to ammonium sulfate precipitation the bulk of HO-1 activity precipitated between 0 and 35% saturation, whereas that of HO-2 was precipitated between 35 and 65% saturation. The two forms appeared as immunologically different entities, in so far as a crossreactivity between antibody raised against HO-1 in rabbit and HO-2 could not be detected. Similarities were observed in respect to cofactor requirements for activity, sensitivity to inhibitors, as well as their reactivity towards the substrates used in this study, i.e. hematin, hematoheme, and cytochrome c. Specifically both forms of the enzyme required NADPH-cytochrome c (P-450) reductase, NADPH or NADH, and O2 for activity, and reactions were inhibited by KCN, NaN3, and CO. Both forms cleaved the tetrapyrrole molecule exclusively at the alpha-meso bridge to form biliverdin IX alpha isomer. HO-1 and HO-2 utilized hematin and hematoheme as substrates but not intact cytochrome c.
Theory of Stronger-Signal Capture in FM Reception (1958)

The characteristics of the FM disturbance that is caused by two-signal interference are pointed out and compared with the characteristics of message modulation. The comparison suggests a new role for the amplitude limiter in FM receivers. The limiter spreads out the spectrum which carries the FM disturbance over a frequency range that often exceeds many times the bandwidth requirements of the message modulation. This makes it possible to reject important parts of the interference spectrum by proper filtering in the output of the limiter without substantially affecting the spectrum of the message modulation. A repeated cycle of amplitude limiting and spectrum filtering is found to be an effective scheme for suppressing the disturbance ahead of the discriminator stage, and for improving the capture capabilities of an FM receiver.
p21-Activated Kinase 2 in Neutrophils Can Be Regulated by Phosphorylation at Multiple Sites and by a Variety of Protein Phosphatases (2003)

The p21-activated kinase(Pak) 2 undergoes rapid autophosphorylation/activation in neutrophils stimulated with a variety of chemoattractants (e.g., fMLP). Phosphorylation within the activation loop (Thr(402)) and inhibitory domain (Ser(141)) is known to increase the activity of Pak in vitro, whereas phosphorylation within the Nck (Ser(20)) and Pak-interacting guanine nucleotide exchange factor (Ser(192) and Ser(197)) binding sites blocks the interactions of Pak 2 with these proteins. A panel of phosphospecific Abs was used to investigate the phosphorylation of Pak 2 in neutrophils at these sites. Pak 2 underwent rapid (< or =15 s) phosphorylation at Ser(20), Ser(192/197), and Thr(402) in neutrophils stimulated with fMLP. Phosphorylation at Ser(192/197) and Thr(402) were highly transient events, whereas that at Ser(20) was more persistent. In contrast, Pak 2 was constitutively phosphorylated at Ser(141) in unstimulated neutrophils and phosphorylation at this site was less sensitive to cell stimulation than at other residues. Studies with selective inhibitors suggested that a variety of phosphatases might be involved in the rapid dephosphorylation of Pak 2 at Thr(402) in stimulated neutrophils. This was consistent with biochemical studies which showed that the activation loop of GST-Pak 3, which is homologous to that in Pak 2, was a substrate for protein phosphatase 1, 2A, and a Mg(2+)/Mn(2+)-dependent phosphatase(s) which exhibited properties different from those of the conventional isoforms of protein phosphatase 2C. The data indicate that Pak 2 undergoes a complex pattern of phosphorylation in neutrophils and that dephosphorylation at certain sites may involve multiple protein phosphatases that exhibit distinct modes of regulation.
Developmental hematopoiesis in normal human fetal blood (1991)

Using an easy and safe procedure for fetal blood sampling in utero, we studied 3,415 fetuses for prenatal diagnosis. Retrospectively, 2,860 normal blood samples, performed from the 18th week of gestation to the end of pregnancy, were selected. Differentials were evaluated in 732 cases. Burst-forming unit erythroid (BFU-E) and erythropoietin (Epo) were measured in 27 and 163 cases, respectively. Total nucleated cell and platelet counts did not change from the 18th to the 30th week of gestation. The lymphocytes represented the main population and the decrease of normoblastic cells made up for the increase in neutrophils. The increase of red blood cells and hemoglobin was substantial during the studied period. At mid trimester threefold more BFU-E were obtained than at birth. Epo levels remained stable throughout the pregnancy and no correlation was found between Epo and gestational age. These normal values of fetal erythropoiesis will improve our knowledge of physiology and provide a better insight into developmental hematopoiesis.
Trochanteric transfer in total hip replacement: Effects on the moment arms and force‐generating capacities of the hip abductors (1996)

A three-dimensional computer model of the pelvis, femur, gluteus medius, and gluteus minimus was used to evaluate the changes in muscle moment arms and force-generating capacities caused by alterations in the location of the greater trochanter. In the first part of this study, the hip center and all other aspects of joint geometry remained unaltered, while we examined changes in abduction moment arms that resulted from transfer of the trochanteric fragment to a wide variety of positions on the femur. The largest increase in average abduction moment arm was 11% (0.5 cm), which occurred with an anterolateral transfer. Most transfers resulted in moment arm changes of less than 5%. In the second part of this study, the hip center was displaced 2 cm superiorly, and the effects of a distal trochanteric transfer on the moment arms and force-generating capacities of the abductors were analyzed. The superior displacement caused a 13% decrease in the moment arm of the abductors and a 43% decrease in their force-generating capacity. The moment arm was not restored by distal transfer of the greater trochanter; however, distal transfer had the major advantage of restoring muscle lengths and force-generating capacities. These results suggest that trochanteric transfer should be considered primarily as a means to restore muscle length because it has limited potential to increase the moment arms of the two primary hip abductors.
MICRO-OPTICAL RESONATORS FOR MICROLASERS AND INTEGRATED OPTOELECTRONICS (2005)

Abstract Optical microcavities trap light in compact volumes by the mechanisms of almost total internal reflection or distributed Bragg reflection, enable light amplification, and select out specific (resonant) frequencies of light that can be emitted or coupled into optical guides, and lower the thresholds of lasing. Such resonators have radii from 1 to 100 μm and can be fabricated in a wide range of materials. Devices based on optical resonators are essential for cavity-quantum-electro-dynamic experiments, frequency stabilization, optical filtering and switching, light generation, biosensing, and nonlinear optics.
α-Dicarbonyls Increase in the Postprandial Period and Reflect the Degree of Hyperglycemia (2001)

Increased production of MG and 3-DG occur with greater PPGE, whereas HbA1c does not reflect these differences. Reduced PPGE also leads to increased production of D-lactate, indicating a role for increased detoxification in reducing MG levels. The higher postprandial levels of MG and 3-DG observed with greater PPGE may provide a partial explanation for the adverse effects of glycemic lability and support the value of agents that reduce glucose excursions.
10 Gbit/s optical single sideband system (1997)

An approach for transmitting a digital optical single sideband signal in a self-homodyne detection system has been developed. Simulation results show that 10 Gbit/s of data can be transmitted through conventional singlemode fibre over distances > 1000 km with post-detection electrical dispersion compensation; initial experimental results show transmission of 10 Gbit/s over distances up to 200 km.
Synthesis of 1-cyclohex-1-en-1-ethylamine from cyclohex-1-en-1-acetonitrile (2005)

1-Cyclohex-1-en-1-ethylamine was synthesized from cyclohex-1-en-1-acetonitrile by indirect synthetic method.The effect of reaction temperature,reaction pressure and reaction time on the synthesis of 1-cyclohex-1-en-1-ethylamine were emphatically studied.The optimal reaction conditions have been obtained: reaction temperature is 150℃,reaction pressure is 1.2 MPa,reaction time is 1.5 h,under this condition,the yield of 1-cyclohex-1-en-1-ethylamine is up to 85.3% at last.
Point mutations of human interleukin‐1 with decreased receptor binding affinity (1986)

Interleukin-1 (IL-1) is a monocyte-derived polypeptide hormone that interacts with a plasma membrane receptor. We have used oligonucleotide-directed mutagenesis to construct mutant human IL-1 proteins. Three different point mutants in a unique histidine residue (position 30) exhibited varying degrees of reduced IL-1 receptor binding affinity, whereas point mutants at five other residues behaved normally. Structural analysis of these mutant proteins by nuclear magnetic resonance spectroscopy detected no (or only minor) conformational changes relative to wild-type IL-1. These data suggest that the unique histidine residue influences the architecture of the receptor binding site on human IL-1.
An Analysis of Visual Adaptation and Contrast Perception for Tone Mapping (2011)

Tone Mapping is the problem of compressing the range of a High-Dynamic Range image so that it can be displayed in a Low-Dynamic Range screen, without losing or introducing novel details: The final image should produce in the observer a sensation as close as possible to the perception produced by the real-world scene. We propose a tone mapping operator with two stages. The first stage is a global method that implements visual adaptation, based on experiments on human perception, in particular we point out the importance of cone saturation. The second stage performs local contrast enhancement, based on a variational model inspired by color vision phenomenology. We evaluate this method with a metric validated by psychophysical experiments and, in terms of this metric, our method compares very well with the state of the art.
Animal models for the negative symptoms of schizophrenia (2000)

Negative or defect symptoms refer to a reduction in normal functioning. In schizophrenia, negative symptoms encompass, among others, anhedonia, flat affect, avolition and social withdrawal. These symptoms have been found to be particularly prominent in the more chronic phase of the illness and seem to be virtually insensitive to current antipsychotic treatment. This review focuses on the possibilities and limitations of animal models for the negative symptoms of schizophrenia. Following a review of the negative symptoms in schizophrenia, attention is focused on the two symptoms most often modelled in animals - anhedonia and social withdrawal. We then look at the important question of how to model schizophrenic pathology in animals. Since the exact pathology is still far from clear, most efforts have in the past concentrated on using psychotomimetic drugs such as amphetamine or phencyclidine. The recently accumulated knowledge that schizophrenia probably results from disturbances in the normal development of the brain has led to a surge of new animal models in which the long-term consequences of early manipulations are investigated. However, so far these models have predominantly concentrated on the positive rather than the negative symptoms of schizophrenia. The last part of this review is dedicated to the question of validation of animal models for anhedonia and social withdrawal. The general conclusion is that very few models have so far been adequately tested. The lack of currently effective treatment further hampers the study of such validation.
Processing of Ceramic Matrix Composites by Pulsed-CVI and Related Techniques (1998)

P-CVD/CVI is used to densify model pores and to fabricate Nicalon/SiC microcomposites with pyrocarbon or (PyC-SiC)/sub n/ multilayered interphases. The gaseous precursors are hydrocarbons (CH/sub 4/ or C/sub 3/H/sub 8/) for pyrocarbon and CH/sub 3/SiCl/sub 3/-H/sub 2/ for SiC. The best densification conditions for 60; 120 and 320 mum model pores, by pyrocarbon, are T=900-1000degC; P/sub 2/=1-3 kPa and t/sub R/=a few s. Even under such conditions, a thickness gradient is always present along the pore axis. Filling ratios as high as 90% are observed for the largest pores. Smooth or rough laminar pyrocarbon is deposited depending on the value of t/sub R/ and hence the maturation of the gas phase. Multilayered (PyC-SiC)/sub n/ interphases (with n=10-30; e(PyC)=3-50 nm and e (SiC)=10 or 30 nm) act as mechanical fuses and are more resistant to oxidation than pyrocarbon interphase. P-CVD/CVI can be used to elaborate highly engineered new ceramics
CRITICAL BEACH EROSION 2005 (2005)

`This dataset indicates the condition of shoreline, determined by the Bureau of Beaches and Coastal Systems staff of Coastal Engineers, for the year 2005. This report is used to document areas of change and to help the beach management staff with prioritizing projects and resources to the areas of greatest need. Created based on the Critical Erosion Report for 2005.
Stereoselective Preparation of (<i>E</i>)-(1,2-Difluoro-1,2-ethenediyl) Bis[tributylstannane] and Stereospecific Synthesis of (<i>E</i>)-1,2-Difluorostilbenes (2002)

[reaction: see text]. The novel bisstannane (E)-(1,2-difluoro-1,2-ethenediyl) bis[tributylstannane] 2 was stereoselectively prepared in a high overall yield through a sequential synthetic route from chlorotrifluoroethylene 1. The synthetic application of this novel bisstannane 2 was exemplified in the Pd(PPh3)4/CuI-catalyzed cross-coupling reactions with aryl iodides, yielding (E)-1,2-difluorostilbenes 3 in moderate to high yields.
Robust ML Detection Algorithm for MIMO Receivers in Presence of Channel Estimation Error (2006)

Capacity of wireless communication systems can be increased enormously using arrays of antenna at transmitter and receiver. However, in these so called multi-input multi-output (MIMO) communication systems, the performance of the signal detection is tightly related to the channel knowledge at the receiver side. Practically, the channel information at the receiver is subject to error because of the outdated data, quantization error, and imperfect channel estimation/measurement. It is known that in the case of imperfect channel knowledge, performance of symbol detection in MIMO communications may severely degrades. The optimum detection method in the sense of symbol error rate in MIMO systems is the maximum likelihood (ME) detection. In this paper, we proposed and studied a couple of robust detection methods that improve the performance of ME detector in MIMO systems in the presence of channel matrix error at the receiver
Reduction of Absorption Loss in Asymmetric Twin Waveguide Laser Tapers Using Argon Plasma-Enhanced Quantum-Well Intermixing (2004)

Lasers based on asymmetric twin waveguide integration technology are limited by the necessity of pumping the tapers to avoid absorption losses within this section of the active region. Here, we demonstrate that the threshold current is reduced by argon plasma-enhanced quantum-well intermixing in the taper. Intermixing induces a (57/spl plusmn/5) nm wavelength blue shift in the emission peak, accompanied by a <12-nm linewidth broadening of the photoluminescence spectrum, indicating minimal material degradation. The threshold current of a 0.6-mm-long laser is reduced by (18/spl plusmn/1)% to (27/spl plusmn/1) mA using an intermixed taper as compared to a nonintermixed structure.
Structural and Dynamic Considerations Towards the Design of Padded Finger Seals (2003)

Finger seals present a compliant seal alternative to brush seals and through their geometric configuration bring about the added potential of hydrodynamic lifting and thus non-contacting operational feature. The fingers' compliance allows both axial and radial adjustment to rotor excursions without damage to the integrity or performance of the seal. The work to be presented here concerns the mapping of the thermofluid and dynamic behavior of repetitive section of the newly proposed design of a two layer Finger Seal. The assembly contains four high pressure (HP) and four low pressure (LP) fingers arranged axially in a staggered configuration, and subject to an axial pressure drop. The numerical 3-D results presented herein were obtained using customized commercial packages CFD- ACE+. The results were obtained in a parametric fashion were the HP side, and the compressibility are the controlling parameters. In addition, two limiting thermal cases were also studied in conjunction with the previously mentioned parameters. The entire study is aimed at generating reliable design procedures for the parametric design of a finger seal. It was found that the geometry proposed provides satisfactory lifting capability for the fingers; that the stiffness of the finger is comparably small to that of the fluid, and thus the displacement transmissibility is mostly close to 1. The stiffness and damping characteristics of the solid padded finger and that of the fluid are also studied and presented on a parametric basis.
Copper, β-amyloid, and Alzheimer's disease: Tapping a sensitive connection (2003)

Understanding the biological basis of social anxiety disorder (SAD), one of the most disabling of the anxiety disorders, will allow for novel treatment strategies to be developed. Here, we show that gut microbiota may be such a target. Mice ...Social anxiety disorder (SAD) is a crippling psychiatric disorder characterized by intense fear or anxiety in social situations and their avoidance. However, the underlying biology of SAD is unclear and better treatments are needed. Recently, the gut ...
An experiment in latency reduction (2002)

Communication latency can be reduced by increasing bandwidth via a sender-based anticipation technique called Parallel Communication. The authors apply this method to anonymous FTP. Their analysis of log files indicates that latency can be reduced to 2 round-trip times, as small as 0.6 round-trip time/file, for a 7x increase in bandwidth. This technique applies to up to 95% of the FTP traffic. This method is expected to be especially useful in reducing latency in automated FTP access. Such as in the World-WideWorld-Wide Web.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>