PurposeEarly detection of appendicitis has increased due to development of computed tomography and ultrasonography, yet we are frequently meeting complicated appendicitis, including...Full Text Available
Objective:The identification of biological markers in order to assess different aspects of COPD is an area of growing interest. The objective of this study was to investigate whether...Full Text Available
The objective of the present study was to test the hypothesis that circulating levels of insulin-like growth factor-I (IGF-I) are inversely associated with inflammatory processes in an elderly background population.
There are no specific diagnostic tests or a gold standard method for measuring disease activity and outcome in spondyloarthropathies (SpA). Many different methods have been developed to assess the signs and symptoms in SpA. The aim of this study was to evaluate the value of scintigraphy, erythrocyte sedimentation rate (ESR), C-reactiveprotein (CRP), and Bath Ankilosing Spondylitis Disease Activity Index (BASDAI) in the evaluation of disease activity in early axial SpA diagnosed with magnetic resonance imaging (MRI). Thirty early MRI-positive axial SpA patients (23 males, 7 females) with a median age of 35 (18?55) years and a median duration of inflammatory low back pain of 24 (8?60) months were included in the study. In the patients with sacroiliitis, the sensitivity, specificity, and pos...
Pyogenic sacroiliitis is a rare entity in children. Diagnosis is often delayed because of its variable clinical presentation, low suspicion by the examining physician, and rare findings on radiographs. Delayed diagnosis, however, results in complications such as iliopsoas abscess. We report the case of a 12-year-old girl hospitalized with a 21-day history of fever, pain in the left iliac fossa, and flexion contracture of the hip. On examination, she had fever (38.9 ^oC), psoitis, localized tenderness at the left sacroiliac joint, and pain elicited by lateral compression of the pelvis. The abdominal examination was normal. The erythrocyte sedimentation rate was 130mm in the first hour, C-reactiveprotein was 186mg/l, and the white blood cell count was 18,400/mm^3, with 79% neutrophils. Urin...
Light increased the rate of LHCP synthesis as measured by pulse-labeling with /sup 35/SO/sub 4/ and immunoprecipitation with antibody specific for Euglena LHCP. In addition to the mature LHCP, 26,000 daltons, the LHCP specific antibody immunoprecipitated large amounts of several proteins having molecular weights of approximately 100,000. On immunoblots of immunoprecipitated unlabeled protein, the antibody only detected the mature LHCP suggesting that the high molecular weight proteins are not LHCP aggregates produced during immunoprecipitation. After a 10 min pulse with /sup 35/SO/sub 4/, the 100,000 dalton proteins constituted over 80% of the immunoprecipitated material. In a subsequent chase, the radioactivity in the 100,000 dalton proteins decreased and the radioactivity in the mature LHCP increased suggesting a precursor-product ...
The disruption of primary innate immune function of the epidermal layer of the skin accounts for the susceptibility of individuals using bleaching agents to localized or systemic infections. This subverted innate immunity in these people may lead to other pathological conditions. The resultant effects of skin bleaching and phagocytes activation in response to infections have not been studied in Nigerians using bleaching agents. The present study therefore assessed the levels of C-reactiveprotein (CRP), albumin, total antioxidant potential (TAP), total plasma peroxides (TPP), oxidative stress index (OSI) and malonaldehyde (MDA) in the users bleaching agents. Thirty (30) people who had used bleaching agents for average of 4.9 + 1.2 years participated in this study. They were recruited from various schools and markets within the city of Ibadan, Oyo State, Nigeria. Thirty apparently healthy staffs of University College Hospital Ibadan, Ibaadan, ...
The adipocytokine adiponectin is released by adipocytes upon activation of the peroxisome proliferator-activated receptor gamma (PPAR gamma). PPAR gamma has binding sites for thiazolidinediones and free fatty acids (FFAs). To evaluate if adiponectin serum concentrations are synergistically regulated by FFAs and thiazolidinediones IN VIVO plasma FFAs were acutely elevated in healthy subjects pre-treated with rosiglitazone or placebo. Sixteen healthy male subjects (23-37 years) were included in this double-blind, randomized, placebo-controlled parallel-group study. Rosiglitazone 8 mg or placebo was administered daily for 21 days. On the last day plasma FFA concentrations were increased by an intravenous triglyceride/heparin infusion. Blood for determination of adiponectin, C-reactiveprotein (CRP), leptin, resistin, FFAs, glucose, and insulin was drawn at baseline and on day 21 before and after 5 hours of triglyceride/heparin infusion. ...
BackgroundInflammatory markers may be associated with recurrent vascular events after stroke. We aimed to: (1) determine the association between interleukin-6, C-reactive...Full Text Available
The time of appearance of newly synthesized rRNAs and ribosomal proteins (r-proteins) in the ribosomes of pea cotyledons (Pisum sativum L.) during germination was investigated. The ribosomal fraction was isolated and analyzed according to the method of germination of the embryo in the presence of labeled precursors or after pulse labeling of the embryos at different stages of germination. For the identification of newly synthesized rRNAs in the ribosomes we estimated the relative stability of labeled RNAs to the action of RNase, the sedimentation rate, the ability to be methylated in vivo in the presence of (/sup 14/C)CH/sub 3/-methionine, and the localization in the subunits of dissociated ribosomes. The presence of newly synthesized r-proteins in the ribosomes was judged on the basis of the electrophoretic similarity in SDS-disc electrophoresis of labeled polypeptides of purified ribosome preparations ...
Thin films of the protein, lysozyme, have been deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Frozen targets of 0.3-1.0 wt.% lysozyme dissolved in ultrapure water were irradiated by laser light at 355 nm with a fluence of 2 J/cm{sup 2}. The surface quality of the thin lysozyme films of different thickness deposited on 7 mm x 7 mm Si-<1 0 0>-wafers was investigated with scanning electron microscopy and atomic force microscopy. Already at comparatively low thickness, {approx}20 nm, the substrate is covered by intact lysozyme molecules and fragments. The concentration of lysozyme in the ice matrix apparently does not play any significant role for the morphology of the film. The morphology obtained with MAPLE has been compared with results for direct laser irradiation of a pressed lysozyme sample (i.e. pulsed laser deposition (PLD))
Chaperones (stress proteins) are essential proteins to help the formation and maintenance of the proper conformation of other proteins and to promote cell survival after a large variety of environmental...Full Text Available
AGNES is a chopper spectrometer installed at the top of the C3 cold guide of JRR-3 (JAERI, Tokai). In 2004 - 2006, this spectrometer was greatly improved by installing (1) 208 new detectors to make the detector bank complete, (2) new radiation shields composed of Fe (14 mm), polyethylene (50 mm), B4C rubber (10 mm), and Cd (0.5 mm) sheets, (3) a new control system for the anti-frame-overlap chopper rotating simultaneously with the Fermi chopper, (4) a monitor counter at the space between the chopper and monochromator, (5) a neutron guide tube (50 cm) before the monochromator, (6) a new instrument control (monochromators, choppers, beam narrowers, etc.) and measurement control (real-time data monitoring, sample temperature control, etc.) systems, (7) a top-loading type cryostat workable at a wide temperature range of 6 - 480 K. As the results of these improvements, the signal intensity has been increased by 3.3 and the background has been reduced by 1/10 both compared with the data ...
The intracellular concentration of protein may be as high as 400 mg per ml; thus it seems inevitable that within the cell, numerous protein-protein contacts are constantly occurring. A basic biochemical...Full Text Available
Reversion-induced LIM protein (RIL) is a member of the ALP (actinin-associated LIM protein) subfamily of the PDZ/LIM protein family. RIL serves as an adaptor protein and seems to regulate cytoskeletons....Full Text Available
The dynamical decoupling (DD) aims at suppressing the decoherence by means of coherent control pulses. Even if devices exist where instantaneous pulses are an adequate approximation, experimentally a finite duration #tau#_p and a bounded amplitude are inevitable. They are the cause of additional errors which can be corrected by designing the pulse shape appropriately. The new pulse has the overall effect of an ideal, instantaneous pulse with the advantage of decoupling the spin (or qubit) from the bath up to the order O(#tau#_p"3). The limitation of the no-go theorem for #pi# pulses is avoided. Hence, the Uhrig sequence (UDD), originally thought for ideal #pi# pulses, works also for bounded control Hamiltonians. Numerical simulations show that concatenated sequences of real pulses are effective against general ...
Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed.
Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed. (author).
A univibrator and a pulse height discriminator using tunnel diodes and backward diodes are described, along with their applications in pulse shaping and fast coincidence technique. The main advantages achieved are simplicity of design and speed. The characteristics of the two diodes are shown. (auth)
Background and ObjectivePulsed dye laser (PDL) treatment of cutaneous vascular lesions is associated with variable and unpredictable efficacy. Thus, alternative treatment...Full Text Available
... spontaneous radiation of amplifiers within a relatively w~de range of ... pulse widths are 20-30ns, while amplified spontaneous radiation pulse ...
A Pulsed Radiation Dosimetry System designed to measure radiation produced by particle accelerators is described. The problems associated with total-dose measurement of irregular shaped pulses of ionizing radiation have been simplified. The system responds to extremely narrow pulses of charged particles or X-rays using a pin diode as the detector. Direct readout of dose in rads (Si) is displayed on a 3-1/2 digit digital panel meter. The system will operate in either the multiple-pulse or single-pulse mode. The multiple-pulse mode would be useful in monitoring or tuning a linear accelerator. In the single-pulse mode the system will automatically display total dose of a transient event in real time and hold that measurement indefinitely or until the next measurement is made. The system features an automatic reset in either mode.
A large group of diseases, termed protein misfolding disorders, share the common feature of the accumulation of misfolded proteins. The possibility of a common mechanism underlying either the pathogenesis...Full Text Available
Many mutations associated with retinal degeneration lead to the production of misfolded proteins by cells of the retina. Emerging evidence suggests that these abnormal proteins cause cell death...Full Text Available
CAAX proteins are widely involved in global cellular functions such as proliferation, differentiation, and carcinogenesis. As an important modulator of biological activity, signal transduction via protein...Full Text Available
Resistance (R) protein mediated recognition of pathogen avirulence effectors triggers signaling that induces a very robust form of species-specific immunity in plants. The soybean Rpg1-b protein mediates...Full Text Available
Membrane protein structural biology is still a largely unconquered area, given that approximately 25% of all proteins are membrane proteins and yet less than 150 unique structures are available. Membrane...Full Text Available
A device for marking and searching for information on a magnetic carrier is described. In order to increase the noise immunity and reliability of the data recording and reading paths, the recording head is included between the amplifier of the clock pulses for the master oscillator and through the amplifier of the code pulses for the logical element unit. The reproduction head is connected through the code pulse shaper-amplifier with a switch which is connected with the display unit, and through another analogous clock pulse amplifier with a multivibrator.
The wavelength of the free electron laser (FEL) in Osaka University can be continuously varied in the range of 5.0-20.0 #mu#m. The FEL has a double-pulse structure, consisting of a train of macropulses of pulse duration 12 #mu#s. Each macropulse contains a train of 330 micropulses of pulse duration 5 ps. The tunability and picosecond pulses afford new medical and biological applications. However, a macropulse of long pulse duration leads to undesirable secondary effects. Precise control of the macropulse duration is essential for the high-precision applications of the FEL. An FEL pulse control system using acousto-optic modulators has been developed to investigate mechanical (shock-wave) effects of the FEL on living tissues. With this system, we have controlled photoinduced shock waves and determine the mechanism of interaction during FEL-induced tissue ...
The influence of the main factors on device efficiency of pulsed liquid jet pump with gas-liquid piston is analysed, the theoretical equation and its time-averaged solution of pulsed liquid jet pump device efficiency are derived. The theoretical and experimental results show that the efficiency of transmission of energy and mass to use pulsed jet is greatly raised, compared with steady jet, in the same device of liquid jet pump. The calculating results of time-averaged efficiency of pulsed liquid jet pump are approximately in agreement with the experimental results in our and foreign countries
The barrier glow discharge between two planar electrodes, covered with dielectric, is studied under high-voltage pulsed power supply. Wide applications of such type of discharges, in particular, for ozone production, stimulated a number of investigations in this direction. In this work we investigated the dependence of ozone concentration on the duration and the rate of pulse rise of the applied voltage. The thyristor converter circuit with the shortening of input pulses on the base of the saturable throttle was used for the realization of this task. The output pulses with amplitude up to 15 kV, repetition frequency of 1 kHz, pulse duration of 0.3 #mu#s (or 7 #mu#s) and the rate of pulse rise of 0.1 #mu#s were generated with this scheme. Measurements of the ozone concentration produced in the air mixture have shown that its value increased by factor two with ...
Relativistic electron beams are used for generating high power microwaves. These microwave sources require electron beam generators spanning significant ranges in voltage and impedance. The pulsed power technology used to generate these electron beams is presented. Electron beam generators that produce beams with pulse durations in the 10-ns to 100-ns regime consist of an energy-storage section, pulse-shaping section, and an electron beam diode. The energy-storage section is either a Marx generator or capacitor bank-pulsed transformer. The pulse shaping is done with high-voltage transmission lines. The electron beam diode is usually a cold-cathode, space-charge-limited flow device. For longer pulses (/approximately/1 ..mu..s) the energy storage and pulse chaping can be combined. Lumped-element pulse-forming networks ...
Relativistic electron beams are used for generating high power microwaves. These microwave sources require electron beam generators spanning significant ranges in voltage and impedance. The pulsed power technology used to generate these electron beams is presented. Electron beam generators that produce beams with pulse durations in the 10 ns to 100 ns regime consist of an energy storage section, pulse shaping section, and an electron beam diode. The energy storage section is either a Marx generator or capacitor bank-pulsed transformer. The pulse shaping is done with high-voltage transmission lines. The electron beam diode is usually a cold-cathode, space-charge-limited flow device. For longer pulses (approx.1 ..mu..s) the energy storage and pulse shaping can be combined. Lumped-element pulsed-forming networks (PFN) can ...
The time and dose characteristics of the electron and X-ray radiations of a tube, connected to a subnanosecond mega volt accelerator, are measured. By the pulse of the accelerating voltage of #>=# 600 kV with duration of #approx =# 0.3 ns the tube generates approximately 5 x 10"1"2 electrons pulse. The current amplitude equals approximately 5 kA/pulse and the radiation dose-about 5 kGy/pulse. The X-ray radiation dose from the tantalum external target constitutes 0.15 Gy/pulse. The prototypes of the electron and X-ray tubes sufficiently lower volumes, opening new applications in the technique and medicine, are developed
In a seeded high-gain free-electron laser (FEL), where a coherent laser pulse interacts with an ultrarelativistic electron beam, the seed laser pulse can be frequency chirped, and the electron beam can be energy chirped. Besides these two chirps, the FEL interaction introduces an intrinsic frequency chirp in the FEL even if the above-mentioned two chirps are absent. We examine the interplay of these three chirps. The problem is formulated as an initial value problem and solved via a Green function approach. Besides the chirp evolution, we also give analytical expressions for the pulse duration and bandwidth of the FEL, which remains fully longitudinally coherent in the high-gain exponential growth regime. Because the chirps are normally introduced for a final compression of the FEL pulse, some conceptual issues are discussed. We show that to get a short pulse duration, an energy ...
In the process of backward Raman amplification (BRA), the leading layers of the seed laser pulse can shadow the rear layers, thus weakening the effective seeding power and affecting parameters of output pulses in BRA. We study this effect numerically and also analytically by approximating the pumped pulse by the ''*-pulse'' manifold of self-similar solutions. We determine how the pumped pulse projection moves within the *-pulse manifold, and describe quantitatively the effective seeding power evolution. Our results extend the quantitative theory of BRA to regimes where the effective seeding power varies substantially during the amplification. These results might be of broader interest, since the basic equations, are general equations for resonant 3-wave interactions.
The effect of asymmetric laser pulses on electron yield from a laser wakefield accelerator has been experimentally studied using > 10{sup 19} cm{sup -3} plasmas and a 10 TW, > 45 fs, Ti:Al{sub 2}O{sub 3} laser. Laser pulse shape was controlled through non-linear chirp with a grating pair compressor. Pulses (76 fs FWHM) with a steep rise and positive chirp were found to significantly enhance the electron yield compared to pulses with a gentle rise and negative chirp. Theory and simulation show that fast rising pulses can generate larger amplitude wakes that seed the growth of the self-modulation instability and that frequency chirp is of minimal importance for the experimental parameters.
An electronically controllable apparatus is described which modulates a continuous wave laser beam so as to produce an output beam consisting of coherent ''pulses'' that are electronically controllable as to both pulse repetition rate and pulse width. The apparatus includes two acoustic devices positioned so that the laser beam passes through them in sequence, and apparatus or for passing sound waves through the devices to frequency shift the laser radiation as well as to diffract it. Each acoustic device such as generates sound waves containing a group of frequencies which result in spaced pulses. The spreading of a laser beam at which emanates from the first acoustic device is countered by the second acoustic device to produce a collimated, coherently pulsed, laser beam.
Proteins aggregated into spherulite structures of amyloid fibrils have been observed in patients with certain brain diseases such as Alzheimers and Parkinsons. The conditions under which these protein spherulites form and grow are not currently known. In order to illuminate the role of environmental factors on protein spherulites, this research aims to explore the kinetics and mechanisms of spherulite formation and growth, as monitored by optical microscopy, in a range of salt concentrations, and initial protein concentrations for two model proteins: bovine b-lactoglobulin and insulin. These two proteins are significantly different in their size and fibril growth rate, but both of these proteins have been shown previously to form amyloid fibrils and spherulites under low pH conditions. The...
Studies on the regulation of the enterocytic differentiation of the human colon cancer cell line HT-29, which is differentiated in the absence (Glc"-) but not in the presence of glucose (Glc"+), have recently shown that the post-translational processing of sucrase-isomaltase and particularly its glycosylation vary as a function of cell differentiation. Other studies indicate that in undifferentiated HT-29 Glc"+ cells there is an accumulation of UDP-N-acetylhexosamine, which is involved in the glycosylation process. The purpose of the present work is to investigate whether an overall alteration of protein glycosylation is associated with the inability of HT-29 cells to differentiate. At least three alterations are detected: (i) after a 10-min pulse, the incorporation of D-[2-"3H]mannose in undifferentiated cells is severely reduced, compared to differentiated cells. (ii) After a 24-h period of labeling with D-[2-"3H]mannose, undifferentiated ...
A system for real-time neutron radiography of moving objects is described. It comprise a source adapted to generate a continuous uninterrupted series of neutron pulses. Each pulse has a predetermined peak power and duration compatible with the framing times of a real-time video imaging system. A transporter moves an object to be examined to bring sequentially position selected portions of the object in the path of the pulses. Where the object itself has moving components, pulses are sequentially incident on the object. According to any dissimilarities, the object will alter the intensity of the neutrons passing therethrough. In order to record separately the changes in the neutron intensity, for each pulse, an imager is positioned to receive the neutron beam pulses which have been altered by their passage through the object and produce images indicating ...
A system for real-time neutron radiography of moving objects is described. It comprise a source adapted to generate a continuous uninterrupted series of neutron pulses. Each pulse has a predetermined peak power and duration compatible with the framing times of a real-time video imaging system. A transporter moves an object to be examined to bring sequentially position selected portions of the object in the path of the pulses. Where the object itself has moving components, pulses are sequentially incident on the object. According to any dissimilarities, the object will alter the intensity of the neutrons passing therethrough. In order to record separately the changes in the neutron intensity, for each pulse, an imager is positioned to receive the neutron beam pulses which have been altered by their passage through the object and produce images indicating ...
Background and ObjectivesDisruption of the vocal fold extracellular matrix (ECM) can induce a profound and refractory dysphonia. Pulsed dye laser (PDL) irradiation...Full Text Available
We have studied both theoretically and experimentally a new scheme of active pulse compression in a free electron laser (FEL) amplifier. The pulse compression scheme presented here is the following. A frequency-chirped pulse is injected into the FEL interaction region. Because of the high gain and narrow bandwidth of the FEL interaction, only the resonant frequency band of the pulse is actively amplified, resulting in a short pulse of high power coherent radiation at the output of the laser. For our experimental parameters (beam voltage #approx =# 150 kV, current #approx =# 5.0 A, wiggler period #approx =# 3.5 cm and gain #approx =# 10 dB), pulses of a few nanoseconds were generated at #approx =# 10 GHz after an interaction length of 2.30 m, in good agreement with theoretical expectations. For the same input pulses (width > 100 ns, ...
The essential mechanical and electronic parts of a beam pulsing system are described, which reaches an energy resolution of ..delta..E/E=0.1%-0.4% in the energy range from 100 eV and 10 keV.
We report coupling and guiding of pulses of peak power up to 0.3 TW in 1.5 cm long preformed plasma waveguides generated in a high repetition rate argon gas jet. Coupling of up to 52% was measured for 50 mJ, -110 fs pulses injected at times longer than 20 ns, giving guided intensities up to -5x1016 W/cm2. It was found that for short delays between waveguide generation and pulse injection, pulse shortening occurred, with this effect reduced as delay was increased. Injection into the waveguide of two consecutive pulses separated by a few nanoseconds resulted in the reduction of shortening of the second pulse at all delays. Femtosecond time-resolved shadowgrams of the coupling of injected pulses into the waveguide show that there is ?0.5 mm of neutral gas remaining at the waveguide entrance after waveguide generation.
This progress report presents a detailed description of the background, technology and application, and Statement of Work for the development of a coal-fired pulse combustor for residential space heating.
A system is claimed for multiplexing or demultiplexing pulsed laser radiation having an acousto-optical device which is electrically controlled to switch a common path of high pulse rate laser radiation between a plurality of spatially distinct paths for relatively lower pulse rate laser radiation at which the pulses are sequenced according to a predetermined time pattern. The acousto-optical element typically includes a Bragg cell which is electrically driven by a set of distinct frequencies, causing deflection of radiation passing therethrough at a predetermined set of angles whereby pulsed radiation on a single path may be distributed onto the plural separate paths or radiation on plural separate paths of time-sequenced pulses of radiation can be combined into a single path of augmented pulse rate. The control of the acousto-optical ...
An optical klystron is built in the 800 MeV electron storage ring at University of Science and Technology of China for harmonic super-radiation generation. In single bunch operation mode the repetition rate of the spontaneous radiation pulses is about 4.533 MHz, and the repetition rate of the seed laser pulses is about 3 Hz, while the radiation pulse duration is 300 ps. For measuring harmonic radiation a high on/off ratio ICCD is used as an optical switch to reject spontaneous radiation pulses of high repetition rate
... The Effect of the Temperature to Which the Material is Heated on the Process of Formation of Intermetallic Compounds in Magnetic Pulse Welding,. ...
A line-to-plate reactor was set-up in the experimental study on the application of nanosecond pulsed corona discharge plasma technology in environmental pollution control. Investigation on the attenuation and distortion of the amplitude of the pulse wave front and the discharge image as well as the waveform along the corona wire was conducted. The results show that the wave front decreases sharply during the corona discharge along the corona wire. The higher the amplitude of the applied pulse is, the more the amplitude of the wave front decreased. The wave attenuation responds in a lower corona discharge inversely. To get a higher efficiency of the line-to-plate reactor a sharp attenuation of the corona has to be considered in practical design.
We report on the collision of 1.5 ps (FWHM) laser pulses traversing at 17 a short similar 7 ps (FWHM) 46.6 GeV electron bunch. The phase-locked system used to maintain the correct timing of the laser pulses and the appropriate diagnostics are described. The jitter between the laser and electron pulses is determined from the stability of the observed rate of Compton scatters and can be described by a Gaussian distribution with #sigma#_j#approx =#2.2 ps. (orig.).
We propose using large Air Cerenkov Telescopes (ACT's) to search for optical, pulsed signals from extra-terrestrial intelligence. Such dishes collect tens of photons from a nanosecond-scale pulse of isotropic equivalent power of tens of solar luminosities at a distance of 100 pc. The field of view for giant ACT's can be on the order of ten square degrees, and they will be able to monitor 10 to 10$^2$ stars simultaneously for nanosecond pulses of about 6th mag or brighter. Using the Earth's diameter as a baseline, orbital motion of the planet could be detected by timing the pulse arrival times.
Compton backscattering of laser photons near the interaction point of an e"+e"- or e"-e"- collider can be used to produce a #gamma#-#gamma# or #gamma#-e"- collider. This paper describes the laser requirements, including pulse duration, intensity, energy, and wavelength, for such a collider. For most of the proposed, next generation, e"+e"- colliders, the laser wavelength should be in the near-infrared, with a pulse duration of 1 ps or less and an energy of similar 1 J per pulse. Current chirped pulse amplification laser systems in solid state lasing materials are well suited to meet these requirements. These systems are described. ((orig.)).
In terms of the kinetic theory of the interaction between the high-power short-time laser pulses with plasma based on the propagator plotting for the plasma particle distribution functions one studied the generation of the hot electrons and of the fast ions as the relativistic femtosecond laser pulses travelled through the supercritical density plasma. One performed calculations based on the various values of the laser pulse intensity, types of the multiple-charged ions, the plasma inhomogeneity degree. One studied the acceleration mechanisms both of the plasma electrons and ions
In this paper, model analysis into the time-dependent transmembrane potential at the outer cell membrane is presented, for applied high-intensity electric pulses having durations in the nanosecond range or smaller. It is argued that the frequency-dependent dielectric response of cell membranes could be used to advantage for stronger bioeffects by employing shorter pulses. Our model calculations predict faster transmembrane voltages and larger electroporation densities for a given external energy with pulse durations in the subnanosecond regime. This temporal regime would be used, for example, in the electrotherapy of mixed cell ensembles having different dielectric response properties. PMID:21937300
in pulse applications such as magnetic forming. ... In magnetic-forming electric circuitry, the ..... Aspects of Electrohydraulic land Magnetic Forming. ...
BackgroundWe examined the effects of short-term consumption of whey protein isolate on muscle proteins and force recovery after eccentrically-induced muscle damage in healthy individuals.MethodsSeventeen...Full Text Available
Known vertebrate GATA proteins contain two zinc fingers and are required in development, whereas invertebrates express a class of essential proteins containing one GATA-type zinc finger. We isolated...Full Text Available
Thioredoxin, a small, ubiquitous protein which participates in redox reactions through the reversible oxidation of its active center dithiol to a disulfide, is an essential protein in Bacillus...Full Text Available
Storage proteins are deposited into protein storage vacuoles (PSVs) during plant seed development and maturation and stably accumulate to high levels; subsequently, during germination the storage...Full Text Available
The fusogenic orthoreoviruses express nonstructural fusion-associated small transmembrane (FAST) proteins that induce cell-cell fusion and syncytium formation. It has been speculated that the FAST proteins...Full Text Available
The homologous sequences observed for many calcium binding proteins such as parvalbumin, troponin C, the myosin light chains, and calmodulin has lead to the hypothesis that these proteins have homologous...Full Text Available
The changes in protein species synthesized during early Drosophila embryogenesis were characterized by two-dimensional electrophoresis. Of the 261 proteins scored, 68 (26%) show dramatic changes in...Full Text Available
Serum protein and lipid concentrations as well as the serum protein binding of propranolol, diazepam and phenytoin were measured in normal weight and obese volunteers. Concentrations of alpha 1-acid...Full Text Available
A protein evolution strategy is described by which double-stranded DNA fragments encoding defined E. coli protein secondary structural elements (α-helices, β-strands...Full Text Available
Filamin and Cortexillin are F-actin crosslinking proteins in Dictyostelium discoideum allowing actin filaments to form three-dimensional networks. GAPA, an IQGAP related protein, is...Full Text Available
We have used the two-electrode voltage clamp technique and the patch clamp technique to investigate the regulation of ROMK1 channels by protein-tyrosine phosphatase (PTP) and protein-tyrosine...Full Text Available
The characterization of the single-chain protein in Chinese-cobra (Naja naja atra) blood serum, which yields strong specific protection against the venom of the same snake, is reported. The protein,...Full Text Available
A heterobifunctional reagent, N-succinimidyl 3-(2-pyridyldithio)propionate, was synthesized. Its N-hydroxysuccinimide ester group reacts with amino groups and the 2-pyridyl disulphide structure reacts...Full Text Available
It has been sixty years since the Millers first described the covalent binding of carcinogens to tissue proteins. Protein covalent binding was gradually overshadowed by the emergence of DNA...Full Text Available
Protein modifications such as phosphorylation are often studied by two-dimensional gel electrophoresis since the perturbation in the protein’s pI value is readily detected by this method....Full Text Available
Cd-binding protein was extracted from tomato roots and purified on QAE-Sephadex A-25 and on Sephadex G-75 in 1 molar KCl buffer. The protein preparation was light brown and contained predominantly Cd...Full Text Available
The Protein Data Bank in Europe (PDBe; pdbe.org) is actively involved in managing the international archive of biomacromolecular structure data as one of the partners in the Worldwide Protein Data Bank...Full Text Available
The nucleocapsid protein (NC) of retroviruses plays a major role in genomic RNA packaging, and some evidence has implicated the matrix protein (MA) of certain retroviruses in viral RNA binding. To further...Full Text Available
The activity of Src-related protein-tyrosine kinases is repressed by the phosphorylation of a conserved carboxyl-terminal tyrosine by another cytoplasmic protein-tyrosine kinase termed p50csk. In this...Full Text Available
Large quantity of reliable protein interaction data are available for model organisms in public depositories (e.g., MINT, DIP, HPRD, INTERACT). Most data correspond to experiments with the proteins...Full Text Available
In this study, we investigated on a systems level how complex protein interactions underlying cell polarity in yeast determine the dynamic association of proteins with the polar cortical domain (PCD)...Full Text Available
End binding proteins (EBs) are highly conserved core components of microtubule plus-end tracking protein networks. Here we investigated the roles of the three mammalian EBs in controlling microtubule...Full Text Available
Many genetic processes depend on proteins interacting with specific sequences on DNA. Despite the large excess of nonspecific DNA in the cell, proteins can locate their targets rapidly. After initial...Full Text Available
PknB is a member of the newly discovered eukaryotic-like protein serine/threonine kinase (PSTK) family of proteins. The pknB gene was cloned and expressed in Escherichia coli....Full Text Available
Ethylene rapidly and transiently up-regulates the activity of several monomeric GTP-binding proteins (monomeric G proteins) in leaves of Arabidopsis as determined by two-dimensional gel electrophoresis...Full Text Available
During antibiotic drug development, media are frequently spiked with either serum/plasma or protein supplements to evaluate the effect of protein binding. Usually, previously reported serum or plasma...Full Text Available
Computer-assisted analysis revealed a striking sequence similarity between the putative 24-kDa protein (p24) encoded by open reading frame (ORF) 5 of beet yellows closterovirus and the coat protein...Full Text Available
Zipper-interacting protein kinase (ZIPK) is a member of the death-associated protein kinase family associated with apoptosis in nonmuscle cells where it phosphorylates myosin regulatory light chain...Full Text Available
Tooth enamel biomineralization is mediated by enamel proteins synthesized by ameloblast cells. Two classes of proteins have been described: enamelins and amelogenins. In lower vertebrates the absence...Full Text Available
The Protein Data Bank contains the description of more than 45,000 three-dimensional protein and nucleic-acid structures today. Started to exist as the computer-readable depository of crystallographic...Full Text Available
BackgroundThe fast growing Protein Data Bank contains the three-dimensional description of more than 45000 protein- and nucleic-acid structures today. The large majority of the data...Full Text Available
Chromatographic and electrophoretic studies have shown that the subunits of the crystalloid protein, isolated from mature castor bean (Ricinus communis L. cv Hale) seed endosperm protein...Full Text Available
Alpha-hemoglobin-stabilizing protein (AHSP) is an erythroid-specific protein that acts as a molecular chaperone for the free α chains of hemoglobin. Evidence strongly suggests...Full Text Available
We report on a time-resolved measurement of self-amplified spontaneous emission free-electron laser (FEL) pulses. We observed that the spikes in such FEL pulses have an intrinsic positive chirp and the energy chirp in the electron bunch mapped directly into the FEL output. The measurement also provides rich information on the statistics of the FEL pulses.
Computer simulations and experiments indicate that we can shape the infrared picosecond pulses of the Mark III FEL in amplitude, frequency, and phase. Strongly modulated fundamental and second harmonic pulses have been generated by operating the Mark III FEL in the regime of strong sideband growth. In this paper, we present the results of simulations and experiments for second harmonic generation with fundamental inputs from 2 to 3 {mu}m.
We present a monolithic, self-starting, all-PM, stabilized Yb-fiber laser, pulse-compressed in a hollow-core PM photonic crystal fiber, providing the 370 fs pulses of 4 nJ energy with high mode quality.
The mz8310 device support module provides support for the following record types: event, pulseCounter, pulseDelay, and pulseTrain. No driver support is needed. Up to 4 mz8310 modules are supported. Each 8310 module contains 10 channels, which are identified as signals O,...9. Each channel is individually configurable. Each mz83 10 has two Am9513 Timing Controller chips. Each Am9513 has 5 counters.
The receptor-associated protein (RAP) is a molecular chaperone that binds tightly to certain newly synthesized LDL receptor family members in the endoplasmic reticulum (ER) and facilitates their delivery...Full Text Available
Phospholemman (PLM), a member of the FXYD family of regulators of ion transport, is a major sarcolemmal substrate for protein kinases A and C in cardiac and skeletal muscle. In the heart, PLM...Full Text Available
Summary: Protein features are often displayed along the linear sequence of amino acids that make up that protein, but in reality these features occupy a position in the folded proteins 3D space. Mapping sequence features to known or predicted protein structures is useful when trying to deduce the function of those features and when evaluating sequence or structural predictions. To facilitate this goal, we developed PDBpaint, a simple tool that displays protein sequence features gathered from bioinformatics resources on top of protein structures, which are displayed in an interactive window (using the Jmol Java viewer). PDBpaint can be used either with existing protein structures or with novel structures provided by the user. The current version of PDBpaint allows the visualization of annot...
Male reproductive proteins (MRPs), associated with sperm and semen, are the moieties responsible for carrying male genes into the next generation. Evolutionary biologists have focused on their...Full Text Available
We identify new organelles associated with the vacuolar system in plant cells. These organelles are defined biochemically by their internal content of three integral membrane proteins: a chimeric reporter...Full Text Available
BackgroundFunction exertion of specific proteins are key factors in disease progression, thus the systematical identification of those specific proteins is a prerequisite to understand...Full Text Available
Protein isolated from hen egg-white and functions as a bacteriostatic enzyme by degrading bacterial cell walls. First enzyme ever characterized by protein ...
Among the investigations conducted on the space shuttle flight STS 3 March 1982 was an experiment in which a 1-keV, 100-mA electron gun was pulsed at 3.25 and 4.87 kHz. The resultant waves were measured with a broadband plasma wave receiver. At the time of flight the experimental setup was unique in that the electron beam was square wave modulated and that the shuttle offered relatively long times for in situ measurements of the ionospheric plasma response to the VLF pulsing sequences. In addition to electromagnetic response at the pulsing frequencies the waves exhibited various spectral harmonics as well as the unexpected occurrence of satellite lines around those harmonics. Both phenomena occurred with a variety of different characteristics for different pulsing sequences.
Recently a new method of controlling the pulse length of a short-pulse free-electron laser (FEL) has been developed. By modulating the synchronism between the optical and electron pulses in the FEL cavity, it was found that the output power and the micropulse length of the FEL beam oscillates at the modulation frequency. In this paper, we study theoretically the behavior of the micropulse length, both in the high loss (steady state) regime and the low loss (limit cycle) regime, when a modulated desynchronism is applied. In order to do this, we analyze the dynamics of a short-pulse FEL oscillator. The modulation frequency value plays an important role in the dynamics. We find that there is a resonantlike phenomenon between the externally applied desynchronism modulation and the limit cycle oscillation without modulation of a free-electron laser.
The detection of explosives is a notoriously difficult problem, especially at stand-off distances, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring optimal dynamic detection to exploit the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity of explosives signatures while reducing the influence of noise and the signals from background interferents in the field (increase selectivity). These goals are being addressed by operating in an optimal nonlinear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe ...
The dynamic response of cylindrical and ring-shaped YBaCuO bulk parts to pulsed magnetic fields is calculated by using small sets of finite elements. Some comparisons with experimental results are provided, and they give confidence in the modelling of the superconducting properties. Transient magnetizations as a function of time and space as well as shapes and absolute values of trapped magnetic flux profiles are presented. The influence of the sample geometry is investigated for different millisecond pulsed magnetization processes. Results are reported for different radial thicknesses and heights, different pulse durations, peak magnetic fields and pulse sequences with and without stepwise cooling. Comparisons concerning the achievable trapped magnetic field and flux are made, and implications for the use of high-temperature superconductor bulk parts as cryo-permanent magnets in potential applications ...
Calculations relating to two experiments that demonstrate coherent control of preformed rubidium-85 molecules in a magneto-optical trap using ultrafast laser pulses are presented. In the first experiment, it is shown that pre-associated molecules in an incoherent mixture of states can be made to oscillate coherently using a single ultrafast pulse. A novel mechanism that can transfer molecular population to more deeply bound vibrational levels is used in the second. Optimal parameters of the control pulse are presented for the application of the mechanism to molecules in a magneto-optical trap. The calculations make use of an experimental determination of the initial state of molecules photoassociated by the trapping lasers in the magneto-optical trap and use shaped pulses consistent with a standard ultrafast laser system.
Ultra-short-pulse reflectometry is studied by means of the numerical integration of a one-dimensional full-wave equation for ordinary modes propagating in a plasma. The numerical calculations illustrate the potential of using the reflection of ultra-short-pulse, microwaves as an effective probe of the density profile even in the presence of significant density fluctuations. The difference in time delays of differing frequency components of the microwaves can be used to deduce the density profile. The modification of the reflected pulses in the presence of density fluctuations is examined and can be understood based on considerations of Bragg resonance. A simple and effective profile-reconstruction algorithm using the zero-crossings of the reflected pulse and subsequent Abel inversion is demonstrated. The robustness of the profile reconstruction algorithm in the presence of a sufficiently small amplitude ...
The advances in laser technology have made available very short and intense laser pulses which can be used to seed a high-gain single-pass free-electron laser (FEL) amplifier. With these seed pulses, a regime of the FEL interaction where the radiation evolution is simultaneously dominated by nonlinear effects (saturation) and time-dependent effects (slippage) can be explored. This regime is characterized by the propagation of a solitary wavelike pulse where the power of the optical wave grows quadratically with time, its pulse length decreases and the spectral bandwidth increases. We analyze the interplay between the field and particle dynamics of this propagation regime which was studied before and termed super-radiance. Furthermore we analyze the properties of the strong higher-order harmonic emission from this wave and its behavior when propagating in a cascade FEL. The super-radiant ...
Pseudomonas syringae is a gram-negative bacterial plant pathogen that is dependent on a type III protein secretion system (TTSS) and the effector proteins it translocates into plant...Full Text Available
Biological cells of the nitrogen fixating bacteria Xanthobacter autotrophicus GZ 29 have been cultivated with 57-Fe, and from the nitrogenase of these cells the 57-Fe marked molybdenum-iron-protein is extracted. The Moessbauer spectra of this enzyme show that the structure of the iron cluster is similar to the structure in the molybdenum-iron-proteins of Azotobacter vinelandii, Klebsiella pneumoniae or Clostridium pasteurianum.
Protein bodies within the endosperm of castor bean (Ricinus communis L. cv. Hale) seeds arise from numerous small vacuoles which progressively become filled with storage protein, of...Full Text Available
In a series of experiments carried out on young and adult rabbits the effect of isocaloric low protein diets containing 4% or 8% protein compared with a diet containing 21% protein on Obeliscoides cuniculi infection was studied. The pathogenesis, resistance and local immunity were assessed after single infections with 10,000 larvae or reinfection with 5000 larvae. Live weight gain was reduced in young and adult rabbits fed the low protein diets, but the establishment of parasites was not substantially influenced by protein deprivation. However, development of worms in the histotrophic phase and parasite fecundity were impaired in association with the low protein diet. Moreover, mild anaemia as well as changes in the mucosal immune response as a result of infection were related to the level of dietary protein. (author). 30 refs, 6 figs, 5 ...
Assembly of icosahedral capsids of proper size and symmetry is not understood. Residue F170 in bacteriophage P22 coat protein is critical for conformational switching during assembly. Substitutions at this site cause assembly of tubes of hexamerically arranged coat protein. Intragenic suppressors of the ts phenotype of F170A and F170K coat protein mutants were isolated. Suppressors were repeatedly found in the coat protein telokin-like domain at position 285, which caused coat protein to assemble into petite procapsids and capsids. Petite capsid assembly strongly correlated to the side chain volume of the substituted amino acid. We hypothesize that larger side chains at position 285 torque the telokin-like domain, changing flexibility of the subunit and intercapsomer contacts. Thus, a sing...
TC inhibits protein synthesis in E. coli by interfering with aminoacyl-tRNA binding to the ribosomal A site, and there is strong evidence that such inhibition results from TC binding to a high affinity site on the 30S subunit. The SPORE approach has been used to define those 30S proteins that are potentially important for high affinity TC binding, measured as the (/sup 3/H)-TC co-sedimenting with the reconstitution particle through a sucrose density gradient. Reverse phase-HPLC has been used both to prepare ribosomal proteins and to analyze the protein content of reconstituted particles. The results obtained so far show that protein S7, as well as some proteins linked to S7 in the 30S assembly map, are important for TC binding, whereas other ribosomal proteins are not. These results are in very good accord with their earlier photoaffinity ...
White spot syndrome virus (WSSV) is the causative agent of the white spot disease of shrimp. Penaeus monodon were captured from Muttukadu Estuary in Chennai, India, transported to the laboratory and maintained in an aerated system with continuous water circulation-biofiltration. WSSV-free P. monodon were challenged by feeding them only once with WSSV-infected tissues of P. monodon. Cumulative mortality (100%) of the infected individuals was determined. Tissues from infected and uninfected shrimp such as muscles, hepatopancreas, heart, gills and eye tissues (100mg of each) and haemolymph (50 microl) were subjected to SDS-PAGE. In infected muscle tissue, six newly expressed proteins were detected. In infected haemolymph, four new proteins and three intensely expressed high molecular weight proteins were observed. Three intensely expressed high molecular weight proteins were detected in infected heart ...
In this paper, molecular quantum computation is numerically studied with the quantum search algorithm (Grover's algorithm) by means of optimal control simulation. Qubits are implemented in the vibronic states of I_2, while gate operations are realized by optimally designed laser pulses. The methodological aspects of the simulation are discussed in detail. We show that the algorithm for solving a gate pulse-design problem has the same mathematical form as a state-to-state control problem in the density matrix formalism, which provides monotonically convergent algorithms as an alternative to the Krotov method. The sequential irradiation of separately designed gate pulses leads to the population distribution predicted by Grover's algorithm. The computational accuracy is reduced by the imperfect quality of the pulse design and by the electronic decoherence processes that are modeled by the non-Markovian ...
The authors investigated the application of pulsed corona discharge process to the removal of SO{sub 2} and NO{sub x} from industrial flue gas of an ioron-ore sintering plant. This study was performed on a pilot scale, which is the most advanced demonstration of this process. The flow rate of 5000 m{sup 3}/h of the flue gas was successfully treated. The electrode structure of the corona reactor is the same with that of conventional electrostatic precipitator. The authors made use of magnetic pulse compression technology to produce repetitive high voltage pulse. Pulse width (full width at half maximum) was reduced to less than 1 {micro}s by connecting a resister in parallel with the corona reactor. An inductor was added to the resister in series to minimize the loss by restricting the current flowing through the resister. By this way, they were able to deliver pulse power with peak ...
Sodium-dependent high-affinity choline uptake was measured in various regions of the brains of rats irradiated for 45 min with either pulsed or continuous-wave low-level microwaves (2,450 MHz; power density, 1 mW/cm2; average whole-body specific absorption rate, 0.6 W/kg). Pulsed microwave irradiation (2-microseconds pulses, 500 pulses/s) decreased choline uptake in the hippocampus and frontal cortex but had no significant effect on the hypothalamus, striatum, and inferior colliculus. Pretreatment with a narcotic antagonist (naloxone or naltrexone; 1 mg/kg i.p.) blocked the effect of pulsed microwaves on hippocampal choline uptake but did not significantly alter the effect on the frontal cortex. Irradiation with continuous-wave microwaves did not significantly affect choline uptake in the hippocampus, striatum, and hypothalamus but decreased the uptake in the frontal cortex. The ...
A high power Free-Electron Laser (FEL) has lased at a wavelength of 22 #mu#m at the Japan Atomic Energy Research Institute (JAERI). The maximum power on a macro-pulse average is 1.7 kW, and it corresponds to an FEL energy of 160 #mu#J/micro-pulse. Extraction efficiency from the electron beam to the FEL radiation was measured to be 5.3% by an energy analyzer, when the maximum FEL power was coupled out. The rms wavelength spread was measured to be 4.6% at the same time. The extraction efficiency, in general, has a maximum value near the zero detuning length of an optical cavity, where (in contrast) the single-pass gain becomes smallest. A high peak current and a long macro-pulse duration are therefore indispensable for realizing high efficiency. The electron beam energy is 16.5 MeV, and the average current is 5.3 mA at a micro-pulse repetition rate of 10.4 MHz. The macro-pulse ...
The US Department of Energy`s Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and also ...
The US Department of Energy's Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and ...
Apparatus and method for selective measurement of tritium oxide in an environment which may include other radioactive components and gamma radiation, the measurement including the selective separation of tritium oxide from a sample gas through a membrane into a counting gas, the generation of electrical pulses individually representative by rise times of tritium oxide and other radioactivity in the counting gas, separation of the pulses by rise times, and counting of those pulses representative of tritium oxide. The invention further includes the separate measurement of any tritium in the sample gas by oxidizing the tritium to tritium oxide and carrying out a second separation and analysis procedure as described above.
A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.
The relaxation oscillation of the amplified spontaneous radiation pulses emitted from a single-mirror Cu/CuBr laser has been observed for the first time and the experimental characteristics of the relaxation oscillation were obtained. In addition, the spatial and temporal distributions of the light pulse intensity of the amplified spontaneous radiation were also measured and found to be comparatively and uniform. The spatial coherence of the amplified spontaneous radiation was found to be better than that of the laser with the same lasant.
Measurements of low-energy (#approx#10"- "1"0 J) femtosecond laser pulse durations have been carried out on the basis of second-order autocorrelation function analysis. The scheme of non collinear second harmonic generation realized in KDP crystal has been used for increasing of the measurement contrast and accuracy. Proposed scheme can be used for measurements in wide enough ranges of laser pulse durations (from tens femto seconds to hundreds picoseconds) and energies. (authors)
Eight cross spiders (Araneus diadematus) were exposed overnight (16 h) during web-building activity to pulsed 9.6-GHz microwaves at average power densities of 10, 1, and 0.1 mW/sq. cm. (estimated SARs 40, 4, and 0.4 mW/g). Under these conditions, 9.6-GHz pulsed microwaves did not affect the web-spinning ability of the cross spider.
There is increasing demand to functionalize meso- and nano-porous materials by coating and make the porous substrate biocompatible or environment friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. In the current work the pulsed laser deposition (PLD) method is used for coating Ni{sub 3}Al-based meso-porous membranes with diamond-like carbon (DLC) layers of high thickness homogeneity and adhesion. (orig.)
We study the all-optical time-control of the strong coupling between a single cascade three-level quantum emitter and a microcavity. We find that only specific arrival-times of the control pulses succeed in switching-off the Rabi oscillations. Depending on the arrival times of control pulses, a variety of exotic non-adiabatic cavity quantum electrodynamics effects can be observed. We show that only control pulses with specific arrival times are able to suddenly switch-off and -on first-order coherence of cavity photons, without affecting their strong coupling population dynamics. Such behavior may be understood as a manifestation of quantum complementarity.
The authors investigated the effect of T-2 toxin on rat liver mitochondrial protein synthesis. Isolated rat liver mitochondria were supplemented with an S-100 supernatant from rat liver and an external ATP-generating system. An in-vitro assay employing cycloheximide, and inhibitor of cytoplasmic protein synthesis, and chloramphenicol, and inhibitor of mitochondrial protein synthesis, to distinguish mitochondrial protein synthesis from the cytoplasmic process. Amino acid incorporation into mitochondria was dependent on the concentration of mitochondria and was inhibited by chloramphenicol. The rate of uptake of tritium leucine into mitochondrial protein was unaffected by the addition of T-2 toxin and was not a rate-limiting step in incorporation. However, 0.02 micrograms/ml of T-2 toxin decreased the rate of protein synthesis inhibition correlated with the amount ...
Cell extracts of the thermophile Clostridium thermohydrosulfuricum catalyzed the phosphorylation by (..gamma..-/sup 32/P)ATP of several endogenous proteins with M/sub r/s between 13,000 and 100,000. Serine and tyrosine were the main acceptors. Distinct substrate proteins were found in the soluble (e.g., proteins p66, p63, and p53 of M/sub r/s 66,000, 63,000, and 53,000, respectively) and particulate (p76 and p30) fractions, both of which contained protein kinase and phosphatase activity. The soluble fraction suppressed the phosphorylation of particulate proteins and contained a protein kinase inhibitor. Phosphorylation of p53 was promoted by 10..mu..M fructose 1,6-bisphosphate or glucose 1,6-bisphosphate and suppressed by hexose monophosphates, whereas p30 and p13 were suppressed by 5 ..mu..M brain (but not spinach) calmodulin. Polyamines, including the odd ...
We describe a method for affinity purification of sequence-specific DNA binding proteins that is fast and effective. Complementary chemically synthesized oligodeoxynucleotides that contain a recognition site for a sequence-specific DNA binding protein are annealed and ligated to give oligomers. This DNA is then covalently coupled to Sepharose CL-2B with cyanogen bromide to yield the affinity resin. A partially purified protein fraction is combined with competitor DNA and subsequently passed through the DNA-Sepharose resin. The desired sequence-specific DNA binding protein is purified because it preferentially binds to the recognition sites in the affinity resin rather than to the nonspecific competitor DNA in solution. For example, a protein fraction that is enriched for transcription factor Sp1 can be further purified 500- to 1000-fold by two sequential affinity chromatography ...
Metagenomics projects based on shotgun sequencing of populations of micro-organisms yield insight into protein families. We used sequence similarity clustering to explore proteins with a comprehensive dataset consisting of sequences from available databases together with 6.12 million proteins predicted from an assembly of 7.7 million Global Ocean Sampling (GOS) sequences. The GOS dataset covers nearly all known prokaryotic protein families. A total of 3,995 medium- and large-sized clusters consisting of only GOS sequences are identified, out of which 1,700 have no detectable homology to known families. The GOS-only clusters contain a higher than expected proportion of sequences of viral origin, thus reflecting a poor sampling of viral diversity until now. Protein domain distributions in the GOS dataset and current protein databases show distinct biases. Several ...
A small, permanent-magnet insert structure for the removal of electrons from pulsed, extracted, negative ion beams has been developed at Lawrence Berkeley National Laboratory. The device was computer modeled and designed for an extraction field strength of 3 kV/mm. The testing was carried out with a rf driven multicusp ion source optimized for the production of H{sup {minus}} ions and pulsed at a few Hz with pulse widths of several hundreds of {mu}s. It is demonstrated that the insert structure together with a collar can remove over 98{percent} of electrons from the extracted H{sup {minus}} ion beam without any significant deterioration of the H{sup {minus}} ion output. Application to other negative ion beams can be expected from this magnetic collar insert. {copyright} {ital 1996 American Institute of Physics.}
... main in this state only for 10-8 secs., after which they decay to the meta- stable state (fluorescent level) because of spontaneous radiation or other ...
... at compositions below -AlP 4 the films were still unstable, hydrolysing in room air, and the long term stability of higher aluminium phosphides is in ...
This study was the analyse the relationship between properties of ion nitrided Fe sintered material and parameters of plasma nitriding process. Pure fe sintered materials (relative density : 92%) were fabricated by hot-pressing and nitrided under pulsed DC plasma for 4 hours. The large number of parameters in plasma diffusion treatment allows close control of the process so that surface layers with defined microstructures and properties can be obtained. The number of micropores in nitriding layer can be reduced in pulsed DC plasma by reducing the plasma power and by varying the gas mixture. The phase constitution of compound layer of nitrided Fe sintered material were influenced by gas mixture (N{sub 2} : H{sub 2}) and pulsed ratio (pulse on/off time ratio)
This study was the analyse the relationship between properties of ion nitrided Fe sintered material and parameters of plasma nitriding process. Pure fe sintered materials (relative density : 92%) were fabricated by hot-pressing and nitrided under pulsed DC plasma for 4 hours. The large number of parameters in plasma diffusion treatment allows close control of the process so that surface layers with defined microstructures and properties can be obtained. The number of micropores in nitriding layer can be reduced in pulsed DC plasma by reducing the plasma power and by varying the gas mixture. The phase constitution of compound layer of nitrided Fe sintered material were influenced by gas mixture (N_2 : H_2) and pulsed ratio (pulse on/off time ratio).
To measure electron reactions on a picosecond timescale the investigators developed a picosecond pulse-conductivity technique, which makes use of the electron fine-structure pulses of our LINAC (pulse width 25 vs FWHM) to produce excess electrons and now detects changes in sample conductance under optimum conditions with an instrumental response of 18 ps. This resolution is in agreement with a theoretical estimate. This technique has been successfully applied to study excess electron reactions in solvents covering a mobility range from 0.24 to 100 cm/sup 2/V/sup -1/s/sup -1/; extension to lower mobility liquids seem possible.
A three-dimensional numerical study is performed to explore the effect of pulsed spanwise-periodic surface thermal perturbation (also denoted as thermal bump) in a Mach 1.5 flat plate laminar boundary layer. A high-resolution upwind-biased Roe method is used with the compressive Van Leer harmonic limiter on a suitably refined mesh. The dependence of flow stability characteristics on the variation of thermal bump geometry (shape and dimension) and pulsing properties (disturbance amplitude and frequency) is assessed. It is shown that the finite-span thermal bumps generate streamwise vortices. When the thermal bump is pulsed, vortex shedding is observed, and the streamwise vorticity grows with the downstream distance. Analysis of the integrated disturbance energy indicates that the streamwise...
A flowing carbon dioxide laser was operated at low pressures up to 4 torr. Excitation of the laser was provided using various combinations of direct current (DC), pulsed microwave, and continuous wave (CW) microwave excitation. The microwaves were in the 2.45 GHz band and were coupled into the gas using a slow-wave interdigital transmission line. Laser output of 25 milliwatts (mw) was achieved using a DC discharge only. A combination of a DC discharge and pulsed microwaves doubled the output and resulted in some modulation. Changing the laser gas mixture and pulsed microwave field characteristics allowed some flexibility in the modulation. Lasing was not achieved with excitation from the CW microwaves alone due to the formation of localized discharges. Using pulsed microwaves to sustain the discharge and CW microwaves to pump the laser, a quasi-CW output of 55 mw was achieved.
Presented are the investigation results of electrophysical and physico-mechanical properties of KLF-20, Viksint U-4-21, Viksint KT-73, UF-7-21, KG-184, KL-4, KL-16SE-305, VIAT-1 and PPK-21 sealants, irradiated with sources of continuous and pulse #gamma#-radiation, as well as pulse #gamma#-neutron radiation. It is shown that electrophysical and physico-mechanical properties of sealants after irradiation by continuous #gamma#-radiation up to 10"6 doses and pulse gamma-neutron radiation with neutron fluence of 10"1"3 neutron/cm"2 and #gamma#-radiation dose of 10"4R do not practically change. Electric conductivity and tangent of the angle of dielectric losses increase in the process of irradiation. Electric conductivity depends on irradiation type, is proportional to dose rate and does not depend on temperature and pulse duration.
Development of Portable Normobaric Hypoxia and Pulsed Magnetic Field Firmware System for Enhancement of Radio- and Non-specific Resistance in Workers of Environmentally Hazardous Industries
In the rf-driven free-electron laser (FEL) at the Los Alamos National Laboratory, there are two pulsed-power rf modulators as sources for two tandem, side-coupled 20-MeV linear accelerators. The rf power used to control the cavity fields is supplied by two 5.5-MW modulating anode klystrons operating at a center frequency of 1300.2 MHz. The modulation of the 125 kV klystron is achieved by using a triode switch tube that provides a pulse width up to 300 ..mu..s and a pulse repetition rate up to 10 Hz. This paper describes the present configuration of these two duplicate systems and presents plans for meeting the requirements of future rf FEL experiments at Los Alamos. 12 refs., 5 figs.
Compton backscattering of laser photons near the interaction point of an e{sup +}e{sup -} or e{sup -}e{sup -} collider can be used to produce a {gamma}-{gamma} or {gamma}-e{sup -} collider. This paper describes the laser requirements, including pulse duration, intensity, energy, and wavelength, for such a collider. For most of the proposed, next generation, e{sup +}e{sup -} colliders, the laser wavelength should be in the near-infrared, with a pulse duration of 1 ps or less and an energy of similar 1 J per pulse. Current chirped pulse amplification laser systems in solid state lasing materials are well suited to meet these requirements. These systems are described. ((orig.)).
Recently there has been growth, in interest in non-equilibrium interaction of half-period long optical pulses with matter. To date the optical pulses have been produced by chopping out a half-period long segment from a longer pulse using a semiconductor switch driven by a femtosecond laser. In this paper we present new methods for producing tunable ultra-short optical pulses as short as half an optical period using a free-electron laser driven by electron bunches with a duration a fraction of an optical period. Two different methods relying on the production of coherent spontaneous emission will be described. In the first method we show that when a train of ultra-short optical pulses as short as one half period. We present calculations which show that the small signal gain is unimportant in the early stages of radiation build up in the cavity when the startup process is dominated by ...
We present preliminary analysis for the feasibility of the attosecond x-ray pulses at a proposed FERMI@ELETTRA free electron laser (FEL) [1]. In part 1 we restrict ourselves to minimal modifications to the proposed FEL and consider a scheme for attosecond x-ray production which can be qualified as a small add-on to a primary facility. We demonstrate that at 5-nm wavelength our scheme is capable for production of pulses with an approximate duration of 100 attoseconds at approximately 2 MW peak power and with an absolute temporal synchronization to a pump laser pulse. In part 2 we propose to use an FEL amplifier seeded by a VUV signal and to follow it by the scheme for attosecond x-ray production described in part 1.
Electrically triggered action potentials in the giant alga Chara corallina are associated with a transient rise in the concentration of free Ca(2)+ in the cytoplasm (Ca(2)+(cyt)). The present measurements of Ca(2)+(cyt) during membrane excitation show that stimulating pulses of low magnitude (subthreshold pulse) had no perceivable effect on Ca(2)+(cyt). When the strength of a pulse exceeded a narrow threshold (suprathreshold pulse) it evoked the full extent of the Ca(2)+(cyt) elevation. This suggests an all-or-none mechanism for Ca(2)+ mobilization. A transient calcium rise could also be induced by one subthreshold pulse if it was after another subthreshold pulse of the same kind after a suitable interval, i.e., not closer than a few 100 ms and not longer than a few seconds. This dependency of Ca(2)+ mobilization on single and double pulses ...
Electrically triggered action potentials in the giant alga Chara corallina are associated with a transient rise in the concentration of free Ca2+ in the cytoplasm (Ca2+cyt). The present measurements of Ca2+cyt during membrane excitation show that stimulating pulses of low magnitude (subthreshold pulse) had no perceivable effect on Ca2+cyt. When the strength of a pulse exceeded a narrow threshold (suprathreshold pulse) it evoked the full extent of the Ca2+cyt elevation. This suggests an all-or-none mechanism for Ca2+ mobilization. A transient calcium rise could also be induced by one subthreshold pulse if it was after another subthreshold pulse of the same kind after a suitable interval, i.e., not closer than a few 100 ms and not longer than a few seconds. This dependency of Ca2+ mobilization on single and double pulses can be simulated by a ...
Effect of Abdominal Active Can on DFTs. Introduction: Many patients with implantable cardioverter defibrillators (ICDs) have older lead systems, which are usually not replaced at the time of pulse generator replacement unless a malfunction is noted. Therefore, optimization of defibrillation with these lead systems is clinically important. The objective of this prospective study was to determine if an active abdominal pulse generator (Can) affects chronic defibrillation thresholds (DFTs) with a dual-coil, transvenous ICD lead system. Methods and Results: The study population consisted of 39 patients who presented for routine abdominal pulse generator replacement. Each patient underwent two assessments of DFT using a step-down protocol, with the order of testing randomized. The distal right ...
on this technology has beenproposedas a payload on SpaceStation Freedom to be launched in the near future [1]. Direct detection 4-ary pulse position modula- ...
Mini-LIA is a miniature of a linear induction accelerator developed by China Academy of Engineering Physics and Tsinghua University in 2007. It has been constructed with a thermionic cathode in an electron injector and a metglas core in the induction accelerator cavities. A double-pulsed electron beam was produced for the first time in China on the Mini-LIA with a thermionic cathode in the electron gun and a metglas core in the induction accelerator cavities. A double-pulsed beam current of more than 1.1A was obtained on condition of 80 kV double-pulsed high voltage produced by pulsed power system supplying to the injector and accelerating modules. Some primary experiments for measuring the parameters of Mini-LIA has been performed, and some beam characterizations of Mini-LIA are presented. Further improvement is underway. (authors)
... The three meteorological rocket systems, in order of ... IC3 and IC4 divides the incoming clock pulses f ... at the junction of the temperature sensor and R ...
The heating and current drive systems are being developed to support long pulse, high {beta}, advanced tokamak fusion physics experiments in the KSTAR tokamak. The heating and current drive systems consisting of neutral beam injection (NBI), ion cyclotron waves (ICRF), lower hybrid waves (LHCD) and electron cyclotron waves (ECH/ECCD) have been designed to operate for pulse lengths up to 300 sec and to provide a range of control functions including current drive and profile control. Development of key technologies for high power, long pulse operation has been on going. Substantial progress has been made on areas such as RF launchers, ion source, and high power supplies.
The heating and current drive systems are being developed to support long pulse, high #beta#, advanced tokamak fusion physics experiments in the KSTAR tokamak. The heating and current drive systems consisting of neutral beam injection (NBI), ion cyclotron waves (ICRF), lower hybrid waves (LHCD) and electron cyclotron waves (ECH/ECCD) have been designed to operate for pulse lengths up to 300 sec and to provide a range of control functions including current drive and profile control. Development of key technologies for high power, long pulse operation has been on going. Substantial progress has been made on areas such as RF launchers, ion source, and high power supplies.
... is a standard in the utility industry which is used to study switching transients on power distribution networks and high-voltage transmission lines. ...
Effects of 2450-MHz circularly polarized microwave irradiation on central nervous system functions were studied. Pulsed (microsecond, 500 pps) microwaves decreased high-affinity sodium-dependent choline uptake in the hippocampus and frontal cortex of the rat. The effect on hippocampal choline uptake was blocked by pretreatment with narcotic antagonists. Continuous-wave microwaves of the same power density decreased choline uptake in the frontal cortex only. Furthermore, it was found that the effects of pulsed microwaves on central cholinergic activity are classically conditionable to cues in the exposure environment. The hypothesis that some of the neurological effects of pulsed microwave irradiation are caused by its effect on the auditory system was investigated. Effects of pink noise and pulsed microwaves were compared.
During a Workshop on Gamma-Gamma Colliders in Lawrence Berkeley Laboratory, it was pointed out that an 1-#mu#m laser that can produce 1-J, 1-ps pulses at a few hundred hertz is required. With high-power scalability and ease of formatting, an FEL can be a promising candidate for such a laser. The authors propose an FEL scheme based on chirped-pulsed regenerative amplification to achieve this high peak-power laser. The 1-ps pulse of a solid-state laser will be stretched, amplified, and recompressed to achieve the high peak power. The system is relatively simple and consists of mostly components that have already been demonstrated. This paper will describe the proposal and the important issues of such a scheme.
During a Workshop on Gamma-Gamma Colliders in Lawrence Berkeley Laboratory, it was pointed out that an 1-{mu}m laser that can produce 1-J, 1-ps pulses at a few hundred hertz is required. With high-power scalability and ease of formatting, an FEL can be a promising candidate for such a laser. The authors propose an FEL scheme based on chirped-pulsed regenerative amplification to achieve this high peak-power laser. The 1-ps pulse of a solid-state laser will be stretched, amplified, and recompressed to achieve the high peak power. The system is relatively simple and consists of mostly components that have already been demonstrated. This paper will describe the proposal and the important issues of such a scheme.
A general method for stable-isotope labeling of large proteins is introduced and applied for studies of the E. coli GroE chaperone proteins by solution NMR. In addition to enabling the residue-specific {sup 15}N-labeling of proteins on a highly deuterated background, it is also an efficient approach for uniform labeling. The method meets the requirements of high-level deuteration, minimal cross-labeling and high protein yield, which are crucial for NMR studies of structures with sizes above 150 kDa. The results obtained with the new protocol are compared to other strategies for protein labeling, and evaluated with regard to the influence of external factors on the resulting isotope labeling patterns. Applications with the GroE system show that these strategies are efficient tools for studies of structure, dynamics and intermolecular interactions in large supramolecular complexes, ...
Cocoon sericin plays an important role in the reeling of silk and serves as a valuable biomaterial in the field of biomedicine, skincare, and food industries; however, knowledge about cocoon sericin proteins has been limited. For a comprehensive study on sericin, cocoons of eight varieties of silkworm of different geographic origin and with varied cocoon color were analyzed utilizing proteomics and bioinformatics approaches. The electrophoresis pattern demonstrated some common protein bands for all silkworm varieties and distinctive protein bands for some of those examined in the present study. The Ser2 protein, a new Ser3 protein, and four other novel sericin proteins were identified in cocoons for the first time. Products of both Ser1 and Ser3 genes appear to be ubiquitous in the cocoon ...
Proteins are polymers of amino acids. These macromolecules are synthesized by intracellular machines called {\\it ribosome}. Although, traditionally, the experimental investigation of protein synthesis has been an active area of research in molecular cell biology, important quantitative models of this phenomenon have been reported mostly in the research journals devoted to statistical physics and related interdisciplinary topics. From the perspective of a physicist, protein synthesis is a phenomenon of {\\it classical transport of interacting ribosomes on a messenger RNA (mRNA) template} that dictates the sequence of the amino acids on the protein. Here we bring this frontier area of contemporary research into the classroom by appropriate simplification of the models and methods. In particular, we develope a simple toy model and analyze it by some elementary techniques of non-equilibrium statistical ...
SR proteins are essential splicing factors whose function is controlled by multi-site phosphorylation of a C-terminal domain rich in arginine-serine repeats (RS domain). The protein kinase SRPK1 has been shown to polyphosphorylate the N-terminal portion of the RS domain (RS1) of the SR protein ASF/SF2, a modification that promotes nuclear entry of this splicing factor and engagement in splicing function. Later, dephosphorylation is required for maturation of the spliceosome and other RNA processing steps. While phosphates are attached to RS1 in a sequential manner by SRPK1, little is known about how they are removed. To investigate factors that control dephosphorylation, we monitored region-specific mapping of phosphorylation sites in ASF/SF2 as a function of the protein phosphatase PP1. W...
This study was conducted to investigate the antibacterial effect of BSAP-254 on Bacillus cereus with the induced stress proteins. The BSAP-254 is an antimicrobial peptide isolated from soybean-fermenting bacteria, Bacillus subtilis SC-8. It had a narrow spectrum of activity against B. cereus group. The growth inhibitory effect of BSAP-254 (50??g/mL) reduced the population of B. cereus from >108 to 104 colony-forming units per milliliter within 30?min. In B. cereus exposed to BSAP-254, 14 intracellular proteins were differentially expressed as determined by 2-DE coupled with MS. Of the differentially expressed proteins identified, the stress protein GroEL, which is heat shock protein, was induced in B. cereus exposed to antibacterial peptide.
Wiskott-Aldrich syndrome protein (WASp) is essential for optimal T cell activation. Patients with WAS exhibit both immunodeficiency and a marked susceptibility to systemic autoimmunity. We investigated...Full Text Available
Werner syndrome (WS) is characterized by premature onset of age-associated disorders and predisposition to cancer. The WS protein, WRN, encodes 3′ → 5′ DNA helicase and 3′...Full Text Available
Spin-lattice relaxation rates of protein and water protons in dry and hydrated immobilized bovine serum albumin were measured in the range of 1H Larmor frequency from 10 kHz to 30...Full Text Available
Effector proteins expressed in the esophageal gland cells of cyst nematodes are delivered into plant cells through a hollow, protrusible stylet. Although evidence indicates that effector proteins function...Full Text Available
Synthetic oligoribonucleotides have been used to probe the interaction of MS2 coat protein with the translational operator of the MS2 replicase gene. We have investigated the possible formation of a...Full Text Available
Amidination of aldolase, glyceraldehyde-3-phosphate dehydrogenase, tryptophan synthetase B protein, L-arabinose isomerase, and the catalytic subunit of E. coli aspartate transcarbamylase...Full Text Available
In proteomics, one-dimensional (1D) SDS-PAGE is widely used for protein fractionation prior to mass spectrometric analysis to enhance dynamic range of analysis and to improve identification...Full Text Available
The mini-chromosome maintenance proteins Mcm2–7 are essential for DNA replication. They are loaded onto replication origins during G1 phase of the cell cycle to form a pre-replication complex...Full Text Available
We have previously reported the construction and characterization of an autonomously replicating plasmid in Trypanosoma brucei. In this plasmid the procyclic acidic repetitive protein (PARP) gene promoter...Full Text Available
Altered structure, and hence function, of cellular macromolecules caused by oxidation can contribute to loss of physiological function with age. Here, we tested whether the lifespan of bats, which generally...Full Text Available
The realization that there existed a G-protein coupled signal transduction mechanism developed gradually and was initially the result of an ill fated quest for uncovering the mechanism of action...Full Text Available
Previous studies have shown that salicylates and protein-calorie malnutrition independently compromise maturation and growth of infants. In the present study, pregnant rats were fed normal-and low-protein...Full Text Available
The objective of this research was to determine the role of acidic ribosomal protein (ARP) phosphorylation in translation. Ribosomes (Rbs) from germinated maize (Zea mays L.) axes had...Full Text Available
Surfactant protein A (SP-A), first identified as a component of the lung surfactant system, is now recognized to be an important contributor to host defence mechanisms. SP-A can facilitate phagocytosis...Full Text Available
Cytosol proteins prepared from castor bean endosperm (4-day-old) seedlings stimulate the exchange of [3H]phosphatidylethanolamine between liposomes and mitochondria. The acceleration of the...Full Text Available
The e.p.r. spectra of the Fe-proteins of nitrogenase from all sources studied have unusual features in that they have very anisotropic linewidths and low integrated intensities. These characteristics...Full Text Available
Excessive weight loss due to protein calorie malnutrition (PCM) is a significant problem in Nigerian children. This syndrome may be difficult to differentiate from the wasting disease caused by human...Full Text Available
Brucella abortus is a facultative, intracellular zoonotic pathogen which can cause undulant fever in humans and abortions in cattle. A 14-kDa protein of B. abortus...Full Text Available
Lupus anticoagulant, concentrations of anticardiolipin antibodies, antithrombin III, plasminogen, (free) protein S, protein C, prothrombin, platelet counts, and bleeding times were determined in 74...Full Text Available
Carbenoxolone (CBX) is a semisynthetic derivative of the licorice root substance glycyrrhizinic acid and has been previously reported to induce only heat shock protein 70 [Hsp70, HSPA1A (the systematic...Full Text Available
BackgroundSeveral proteins are known to be markedly expressed in the brain during cerebral ischemia; however, the changes in protein profiles within the ischemic brain after an ischemic...Full Text Available
Protein post-translational modifications are an important biological regulatory mechanism, and the rate of their discovery using high throughput techniques is rapidly increasingly. To make use of this...Full Text Available
The plasma protein binding of phenytoin was investigated in 100 epileptic patients, using equilibrium dialysis at 37 degrees C. The unbound fractions of phenytoin in plasma formed a skewed distribution,...Full Text Available
We demonstrate by using low-temperature high-resolution spectroscopy that red-shifted mutants of green fluorescent protein are photo-interconverted among three conformations and are, therefore, not...Full Text Available
The purpose of the present work was to study the pharmacokinetics and the protein binding (free fraction of the drug) of ceftriaxone (CTX) during pregnancy. Nine pregnant women (ages, 20 to 34 years)...Full Text Available
BackgroundThe expression of human virus surface proteins, as well as other mammalian glycoproteins, is much more efficient in cells of higher eukaryotes rather than yeasts. The limitations...Full Text Available
BackgroundZhx1 to 3 (zinc-fingers and homeoboxes) form a set of paralogous genes encoding multi-domain proteins. ZHX proteins consist of two zinc fingers followed...Full Text Available
The kinetic parameters of single bonds between neural cell adhesion molecules were determined from atomic force microscope measurements of the forced dissociation of the homophilic protein-protein bonds....Full Text Available
Genes of the S100 fused-type protein (SFTP) family are clustered within the epidermal differentiation complex and encode essential components that maintain epithelial homeostasis and barrier functions....Full Text Available
Centrioles are intriguing cylindrical organelles composed of triplet microtubules. Proteomic data suggest that a large number of proteins besides tubulin are necessary for the formation and maintenance...Full Text Available
The exposure of cells to several metal ions stabilizes HIF-1α protein. However, the molecular mechanisms are not completely understood. They may involve inhibition of hydroxylation by either...Full Text Available
Integration of solid-state biosensors and lipid bilayer membranes is important for membrane protein research and drug discovery. In these sensors, it is critical that the solid-state sensing...Full Text Available
In this paper, we report a method of precise in situ x-ray scattering measurements on protein solutions using small stationary sample cells. Although reduction in the radiation damage...Full Text Available
We had previously identified a macrophage surface protein whose expression is highly induced, transient, and specific, as it is restricted to actively fusing macrophages in vitro and in vivo. This protein...Full Text Available
A panel of 16 monoclonal antibodies recognizing M protein (M1) of influenza virus was generated. Competition analyses resulted in localization of 14 monoclonal antibodies to three antigenic sites. Three...Full Text Available
An interactive system for computer analysis of nucleic acid and protein sequences has been developed for the Los Alamos DNA Sequence Database. It provides a convenient way to search or verify various...Full Text Available
Acylation stimulating protein (ASP, C3adesArg) is an adipose tissue derived hormone that stimulates triglyceride (TG) synthesis. ASP stimulates lipoprotein lipase (LPL) activity by relieving feedback...Full Text Available
BackgroundGene expression profiling and the analysis of protein-protein interaction (PPI) networks may support the identification of disease bio-markers and potential drug targets....Full Text Available
Mammals possess multiple insulin-like growth factor (IGF) binding proteins (IGFBPs), and related proteins, that modulate the activity of insulin/IGF signalling (IIS), a conserved neuroendocrine signalling...Full Text Available
Intrinsically disordered proteins are predicted to be highly abundant and play broad biological roles in eukaryotic cells. In particular, by virtue of their structural malleability and propensity...Full Text Available
Dysregulation of the alternative pathway of complement activation, caused by mutations or polymorphisms in the genes encoding factor H, membrane co-factor protein, factor I or factor B, is associated...Full Text Available
Pollen mother cells of the lily (Lilium speciosum) were found to have a histone-H1-like protein (PMCP) not detected in other tissues. The PMCP appears from the late S-G2...Full Text Available
AMP-activated-protein-kinase (AMPK) is a key sensor and regulator of cellular and whole-body energy metabolism and plays a key role in regulation of lipid metabolism. Since lipid metabolism...Full Text Available
We investigated the pathophysiological mechanism by proteomic approach as a possible tool to detect the marker proteins to develop lower urinary tract symptoms following bladder outlet obstruction (BOO)....Full Text Available
Gastrin-releasing peptide receptor (GRPR), a member of the G protein-coupled receptor superfamily, has been utilized for receptor-mediated targeting of imaging and therapeutic agents; here we extend...Full Text Available
BackgroundThe VP2 outer capsid protein Bluetongue Virus (BTV) is responsible for receptor binding, haemagglutination and eliciting host-specific immunity. However, the assembly of...Full Text Available
In isolated rat adipocytes, insulin inhibits lipolysis to a greater extent than would be predicted by the decrease in (-/+)cAMP activity ratio of cAMP-dependent protein kinase (A-kinase), from which it was speculated that insulin promotes the dephosphorylation of hormone-sensitive lipase. They have examined the phosphorylation state of cellular proteins under conditions of varying A-kinase activities in the presence and absence of insulin. Protein phosphorylation was determined by SDS-PAGE electrophoresis of extracts from /sup 32/P-loaded cells; glycerol and A-kinase activity ratios were measured in the cytosolic extracts from control, non-radioactive cells. Increased protein phosphorylation in general occurred over the same range of A-kinase activity ratios, 0.1-0.3, associated with increased glycerol release. The insulin-induced decrease in lipolysis was associated with a decrease in the /sup 32/P ...
The lysosomal catabolism of sulfatide requires arylsulfatase A and a specific sphingolipid activator protein, SAP-1. While most patients with metachromatic leukodystrophy have mutations in the gene...Full Text Available
One selection pressure shaping sequence evolution is the requirement that a protein fold with sufficient stability to perform its biological functions. We present...Full Text Available
SummaryMycobacterium tuberculosis has 10 universal stress proteins, whose function is unknown. However, proteomic and transcriptomic analyses have shown that a number...Full Text Available
The levels of in vitro protein binding of cefonicid and cefuroxime in human adult and neonatal sera were compared. Binding parameters for each drug were determined within the concentration range of...Full Text Available
The Moloney murine leukemia virus (MMLV) belongs to the Retroviridae family of enveloped viruses, which is known to acquire minute amounts of host cellular proteins both on the surface...Full Text Available
Numerous studies have noted that the evolution of new enzymatic specificities is accompanied by loss of the protein's thermodynamic stability (ΔΔG), thus suggesting...Full Text Available
Membrane cofactor protein (MCP or gp45-70) of the complement system is a cofactor for factor I-mediated cleavage of fluid-phase C3b and C3b-like C3, which opens the thioester bond. In the present study...Full Text Available
Parasitic nematodes cause serious diseases in humans, animals, and plants. They have limited lipid metabolism and are reliant on lipid-binding proteins to acquire these metabolites from their hosts....Full Text Available
The question of whether proteins originate from random sequences of amino acids is addressed. A statistical analysis is performed in terms of blocked and random walk values formed by binary hydrophobic...Full Text Available
All organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of cellular stress proteins.'' The authors have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress-induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor-induced, concentration-dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressors effect on cellular physiology. There was a direct concentration-dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis ...
Evaluation of the protective efficacy of recombinant T-cell-reactive proteins of Coccidioides posadasii in a murine model of coccidioidomycosis has led to the discovery of potential...Full Text Available
Mitogen Activated Protein Kinases (MAPKs) are a class of serine/threonine kinases that regulate a number of different cellular activities including cell proliferation, differentiation, survival and...Full Text Available
FXYD1 (phospholemman) is a member of an evolutionarily conserved family of membrane proteins that regulate the function of the Na,K-ATPase enzyme complex in specific tissues and specific physiological...Full Text Available
A commercial blend of essential oil (EO) compounds was added to a grass, maize silage, and concentrate diet fed to dairy cattle in order to determine their influence on protein metabolism by ruminal...Full Text Available
Mutational inactivation of the RB1 tumor suppressor gene initiates retinoblastoma and other human cancers. RB1 protein (pRb) restrains cell proliferation by binding...Full Text Available
The display of proteins such as feed enzymes at the surface of bacterial spore systems has a great potential use for animal feed. Feed enzymes increase the digestibility of nutrients, leading to greater...Full Text Available
Uncoupling protein 2 (UCP2) maps to a region on distal mouse chromosome 7 that has been linked to the phenotypes of obesity and type II diabetes. We recently reported that UCP2 expression is increased...Full Text Available
1 The plasma protein binding of theophylline was determined after addition of [14C]-theophylline (15 micrograms/ml) to plasma from 24 healthy drug-free volunteers and equilibrium dialysis for 2 h at...Full Text Available
The identification of the protein targets for dengue virus-specific T lymphocytes may be useful for planning the development of subunit vaccines against dengue. We studied the recognition by murine...Full Text Available
Merozoite surface proteins have been implicated in the initial attachment to the host red blood cell membrane that begins the process of invasion, an important step in the life cycle of the malaria...Full Text Available
When an exogenous protein, bovine serum albumin, was introduced into the vacuole of a Chara australis internodal cell, it was degraded with time. This degradation proceeded only in...Full Text Available
Reversible protein glutathionylation plays a key role in cellular regulation and cell signaling and protects protein thiols from hyperoxidation. Sulfiredoxin (Srx), an enzyme that catalyzes the reduction...Full Text Available
Circadian clock is implicated in the regulation of aging. The transcription factor CLOCK, a core component of the circadian system, operates in complex with another circadian clock protein BMAL1. Recently...Full Text Available
DNA replication in Escherichia coli cells lacking protein HU was studied. HU has been suggested to be involved in the initiation of replication from in vitro studies. The isolated HU mutants, however,...Full Text Available
Proteins that metabolize or bind the nucleotide second messenger cyclic diguanylate regulate a wide variety of important processes in bacteria. These processes include motility, biofilm formation, cell...Full Text Available
AbstractX-ray diffraction analysis of pressure-induced structural changes in the Aequorea yellow fluorescent protein Citrine reveals the structural basis for the continuous...Full Text Available
Charge reduction electrospray mass spectrometry (CREMS) reduces the charge states of electrospray-generated ions, which concentrates the ions from a protein into fewer peaks spread over a larger...Full Text Available
AbstractThe present study aimed to compare the whole-cell protein profiles of Haemophilus parasuis field isolates by using a computer-based analysis, and evaluate the...Full Text Available
A simulation is developed that qualitatively describes the small-zone-gel-filtration behaviour of a reversibly associating protein. The results reflect the dependence of the apparent molecular weight...Full Text Available
BackgroundOne virulence property of Borrelia burgdorferi is its resistance to innate immunity, in particular to complement-mediated killing. Serum-resistant B....Full Text Available
AIM: To investigate the relation of Fas and Fas ligand (FasL) protein expression with carcinogenesis and metastasis of gastric carcinoma.METHODS: Immunohistochemistry was used to detect Fas and...Full Text Available
Cellular cholesterol homeostasis is controlled by sterol-regulated proteolysis of membrane-bound transcription factors called sterol-regulatory element binding proteins (SREBPs). CPP32, a cysteine protease,...Full Text Available
Sera from multiple sclerosis patients with relapsing-remitting disease and normal subjects were tested for antibody to myelin basic protein by a sensitive radioimmunoassay. The results showed a marginally...Full Text Available
The aim of the present study was to describe the physicochemical characteristics of streptococcal T antigen. T protein isolated from Streptococcus pyogenes type 12 (R53/1077, Colindale) and purified...Full Text Available
The molecular diversity of the gene encoding the outer membrane protein A (OmpA) of Haemophilus parasuis has been unclear. In this study, the structural characteristics, sequence types,...Full Text Available
Recently, CID755673 was reported to act as a highly selective inhibitor of protein kinase D (PKD). In the course of experiments using CID755673, we noticed that it exerted unexpected stimulatory...Full Text Available
Hundreds of genomes have been successfully sequenced to date, and the data are publicly available. At the same time, the advances in large-scale expression and purification of recombinant proteins have...Full Text Available
Certain pathogenic species of Bacillus and Clostridium have developed unique methods for intoxicating cells that employ the classic enzymatic “A-B” paradigm for protein toxins. The binary...Full Text Available
Sustained nigrostriatal dopamine depletion increases the serine/threonine phosphorylation of multiple striatal proteins that play a role in corticostriatal synaptic plasticity, including Thr286...Full Text Available
BackgroundMolecular docking methods are commonly used for predicting binding modes and energies of ligands to proteins. For accurate complex geometry and binding energy estimation,...Full Text Available
PurposeCataract is the leading cause of blindness and is associated with oxidative damage and protein modification in the lens. In the present study, we have employed proteomic and...Full Text Available
The use of sub-nanometer resolution electron density as spatial constraints for denovo and ab-initio structure prediction requires knowledge of protein boundaries...Full Text Available
Amyloid proteins constitute a chemically heterogeneous group of proteins, which share some biophysical and biological characteristics, the principal of which are the high propensity to acquire an incorrect...Full Text Available
BackgroundThe production of high yields of recombinant proteins is an enduring bottleneck in the post-genomic sciences that has yet to be addressed in a truly rational manner. Typically...Full Text Available
Albumin is a multifunctional transport protein that binds a wide variety of endogenous substances and drugs. Insulins with affinity for albumin were engineered by acylation of the epsilon-amino group...Full Text Available
To study the effect of agonist on the TRH (thyrotrophin-releasing hormone) receptor protein, an epitope-tagged receptor was stably expressed in HEK-293 cells (human embryonic kidney 293 cells) and receptor...Full Text Available
The adhesive proteins secreted by marine mussels form a natural glue that cures rapidly to form strong and durable bonds in aqueous environments. These mussel adhesive proteins contain an unusual...Full Text Available
Ataxin-3, the protein involved in Machado-Joseph disease, is able to bind ubiquitylated substrates and act as a deubiquitylating enzyme in vitro, and it has been involved in the modulation of protein...Full Text Available
AMP-activated protein kinase (AMPK) is a key regulator of energy metabolism; its activity is regulated by a plethora of physiological conditions, exercises and many anti-diabetic drugs. Recent...Full Text Available
AMP-activated protein kinase (AMPK) was initially viewed as energy sensor and activated by increased intracellular concentrations of AMP following nutrient deprivation. Physiological or pathological...Full Text Available
Amyloid precursor protein (APP), implicated in Alzheimer's disease, is a transmembrane protein of undetermined function. APP is cleaved by gamma-secretase that releases the APP intracellular domain...Full Text Available
SummaryThe prevalence of paralogous enzymes implies that novel catalytic functions can evolve on preexisting protein scaffolds. The weak secondary activities of proteins, which...Full Text Available
The extreme strength and elasticity of spider silks originate from the modular nature of their repetitive proteins. To exploit such materials and mimic spider silks, comprehensive strategies...Full Text Available
As part of efforts to develop improved methods for NMR protein sample preparation and structure determination, the Northeast Structural Genomics Consortium (NESG) has implemented an NMR screening pipeline for protein target selection, construct optimization, and buffer optimization, incorporating efficient microscale NMR screening of proteins using a micro-cryoprobe. The process is feasible because the newest generation probe requires only small amounts of protein, typically 30-200 ?g in 8-35 ?l volume. Extensive automation has been made possible by the combination of database tools, mechanization of key process steps, and the use of a micro-cryoprobe that gives excellent data while requiring little optimization and manual setup. In this perspective, we describe the overall process used by the NESG for screening NMR samples as part of a sample optimization process, assessing optimal construct design and ...
BackgroundA relevant problem in drug design is the comparison and recognition of protein binding sites. Binding sites recognition is generally based on geometry often combined with...Full Text Available
BackgroundProteins may evolve through the recruitment and modification of discrete domains, and in many cases, protein action can be dissected at the domain level. PDZ domains are...Full Text Available
We show that the expression of an indole-3-acetic acid (IAA)-modified protein from bean seed, IAP1, is correlated to the developmental period of rapid growth during seed development. Moreover, this...Full Text Available
In addition to inducing new transcriptional activities that lead within a few hours to the accumulation of heat shock proteins (Hsps), heat shock activates within minutes the major signaling transduction...Full Text Available
MOM22 is a component of the protein import complex of the mitochondrial outer membrane of Neurospora crassa. Using the newly developed procedure of 'sheltered disruption', we created a heterokaryotic...Full Text Available
The detection efficiency of a lithium glass detector was calculated using MCNP code, and the calculation was compared with the published results in Pulsed Sphere Plan. A lithium glass detector of our own was made, and its neutron efficiency was calculated. The calculated neutron efficiency was verified with both pulsed and steady DD neutrons. Characteristics of Neutron response of "6Li detector was discussed. (authors)
An experimental study of second harmonic generation in a copper-vapor pulsed laser with an ADP crystal is presented. The ratio of the conversion into the second harmonic is found to depend on the average power of the exciting radiation. The maximum conversion ratio was 8.5%. Thermal self-defocusing is the main obstacle to obtaining high average powers at the double frequency.
We discuss optimal detection of fast radio transients from astrophysical objects while taking into account the effects of propagation through intervening ionized media, including dispersion, scattering and scintillation.Our analysis applies to the giant-pulse phenomenon exhibited by some pulsars, for which we show examples, and to radio pulses from other astrophysical sources, such as prompt radio emission from gamma-ray burst sources and modulated signals from extra-terrestrial civilizations.
Saturation of the absorption of hot CO/sub 2/ by 1.6 ns P(18) and P(20) laser pulses at 10.6 ..mu..m has been measured. Coherent propagation calculations with no fitting parameters are in good agreement with the data and are consistent with a substantial hot-band contribution to the P(20) saturation.
The author is exploring the efficiency of pulsed plasma processing in the removal of nitrogen dioxide, nitrogen oxide, and other pollutants. This process uses an electrical discharge to create chemical radicals from air molecules. These radicals can react with pollutants and form harmless compounds. Additives such as hydrocarbons are also used to improve the efficiency of the removal. The efficient removal of nitrogen dioxide has required the presence of dilute aqueous solution of ammonia.
Based on the nonlinear dispersion relation of electromagnetic wave in relativistic plasma, the nonlinear controlling equation for linearly polarized mode is obtained using Karpman's method. The modulation instability of intense laser pulse propagating through relativistic plasma is analyzed and the modulation instability growth rate as a function of perturbation wave number for laser beam propagating through relativistic plasma is given. (authors)
This paper summarizes a method to evaluate the possible effects of magnetohydrodynamic-electromagnetic pulse (MHD-EMP) on power systems. This method is based on the approach adapted to study the impact of geomagnetic storms on power systems. The paper highlights the similarities and differences between the two phenomena. Also presented are areas of concern which are anticipated from MHD-EMP on the overall system operation. 12 refs., 1 fig.
The invention relates to a pulsed laser ablation method of metals and/or dielectric films from the surface of a wafer, printed circuit board or a hybrid substrate. By utilizing a high-energy ultra-short pulses of laser light, such a method can be used to manufacture electronic circuits and/or electro-mechanical assemblies without affecting the material adjacent to the ablation zone.
The paper presents a description of the physical processes governing the variations of the pulse rise-time which occur during the operation of the proportional counter and are due to varying either the count rate or the applied voltage. On the basis of the rise-time concept the differences in the count rate effect observed in various types of proportional counters are discussed.
Operation at ITER specifications of the Kamaboko III ion source for 1000 second pulses of deuterium negative ion beams is underway on the MANTIS test stand. Efficient production of negative ions at low arc power requires injection of cesium into the source, temperature control of the plasma grid, and a period of conditioning of several days. Two different concepts of temperature regulated plasma grids are currently being tested. (author)
This paper describes the methods and systems as utilized in an integrated experimental thermohydraulic/mechanics analysis test program on waterhammer pressure pulses within a revised feedwater sparger of a Loviisa generation VVER-440-type reactor. This program was carried out in two stages: (1) measurements with a strictly limited set of operating parameters at Loviisa NPP, and (2) measurements with the full set of operating parameters on a test article simulating the revised feedwater sparger. The experiments at Loviisa NPS served as an invaluable source of information on the nature of waterhammer pressure pulses and structural responses. These tests thus helped to set the objectives and formulate the concept for series of tests on a test article to study the water hammer phenomena. The heavily instrumented full size test article of a steam generator feedwater sparger was placed within a pressure vessel simulating the steam generator. The ...
Free-electron-laser (FEL) oscillators require a train of high-brightness bunches. Conventional subharmonic bunchers are currently used with rf linacs to generate pulse trains, but the resulting dilution of the transverse phase space and lower beam brightness are unacceptable for high-performance FELs. Recent developments suggest that photoemitters of high quantum efficiency combined with rapid acceleration can produce pulse trains of higher brightness than has been achieved before.
An analytic solution is obtained for the equations of resonance coherent SRS by neglecting the population of the final level of the Raman transition for the systems with the active-medium length that is smaller than the wavelength of the incident light. For the extended systems, a numerical solution is obtained. The energy distribution of the Stokes pulses is found. The large-scale (about 100%) fluctuations of the Stokes radiation energy were observed in the case of unsaturated amplified spontaneous emission. (nonlinear optical phenomena)
Isotopically selective IR multiphoton dissociation of molecules (SF_6, CF_3I) in a pulsed gas-dynamic flow interacting with a solid surface was studied for the first time. A noticeable (severalfold) increase in the yield of products (compared to excitation of molecules in an unperturbed flow) without a substantial decrease in the selectivity of the process was observed. Possible reasons for the effect are discussed. (laser applications and other topics in quantum electronics)
The TESLA Test Facility (TTF) at DESY is a facility producing sub-picosecond electron pulses for the generation of VUV or soft X-ray radiation in a free electron laser (FEL). The same electron pulses would also allow the direct production of high-power coherent radiation by passing the electron beam through an undulator. Intense, coherent far-infrared (FIR) undulator radiation can be produced from electron bunches at wavelengths longer than or equal to the bunch length. The source described in this paper provides, in the wavelength range 50-300 #mu#m, a train of about 1-10 ps long radiation pulses, with about 1 mJ of optical energy per pulse radiated into the central cone. The average output power can exceed 50 W. In this conceptual design, we intend to use a conventional electromagnetic undulator with a 60 cm period length and a maximum field of 1.5 T. The FIR source will use the spent electron beam ...
We have developed a novel insulator concept that involves the use of alternating layers of conductors and insulators with periods less than 1 mm. We have demonstrated that these structures perform 2 to 5 times better than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present new testing results showing exceptional behavior at DC, with gradients in excess of 110kV/cm in vacuum.
A novel approach is presented to extract relevant parameters associated with the energy loss of ejectiles from nuclear reactions obtained by digitizing the signals of a Bragg curve spectrometer. New and more powerful computational paradigms allow a more thorough pulse-shape analysis. This is fulfilled using a back-propagation artificial neural network as a pattern identifier. The known problem of over-training is discussed.
Implementation of quantum logical gates for multilevel systems is demonstrated through decoherence control under the quantum adiabatic method using simple phase modulated laser pulses. We make use of selective population inversion and Hamiltonian evolution with time to achieve such goals robustly instead of the standard unitary transformation language. (letter to the editor)
In this paper, finite-difference time-domain method is used to research the transient electromagnetic pulse (EMP) coupling to the cylinder object which is shielded in another shielding cavity with a hole numerically. The different coupling effectiveness of three transient EMP is simulated. The distribution of the electric field in the shielding cavity and the current on the cavity are researched. The shielding effectiveness is evaluated. (authors)
... Considering these observations, it is most likely that Brucela proteins involved in protective immunity will preferentially stimulate INF-g producing T ...
Experimental investigation data are systematized of free radical states and processes in irradiated proteins. The investigation is performed by the radiospectral methods. Results are discussed in detail of the study of free radicals electronic structure of amino acids, peptides and proteins formed by the action of ionizing radiation. The specificity is stressed of the study of monocrystalls of these compounds by the method of electronic paramagnetic resonance. The nature is also studied of primary centres formed under the effect of radiation on biologically important compounds and their subsequent reactions in solid and liquid solutions. Ion-radical states of different functional groups of the protein molecule are studied. Prospects of the study and the role of anion-radicals in biological processes are discusses.
The effect of protein malnutrition on the metabolism of collagen in bone was studied in young female albino rats after a single injection of "3H-proline. Both specific and total radioactivities of hydroxyproline in the total collagen of the bone were found to decrease in the protein-deficient animals, indicating decreased rate of collagen synthesis. In the urine the amount of hydroxyproline excreted and total radioactivity of "3H-hydroxyproline were greatly decreased. The results of the present investigation therefore clearly indicate decreased synthesis and catabolism of collagen in bones of protein deficient animals compared to controls. (auth.).
Endurance-trained older men have a higher proportion of lean tissue and greater muscle cell oxidative capacity, reversing age-related trends and suggesting major changes in protein metabolism. In this study, protein turnover was determined in 6 middle-aged (52+/-1 yr) men who were well trained (VO_2 max 55.2+/-5.0 ml O_2/kg.min) and lean (body fat 18.9+/-2.8%, muscle mass 36.6+/-0.6%). The maintained habitual exercise while consuming 0.6, 0.9 or 1.2 g protein/kg.day for 10-day periods. N flux was measured from "1"5N in urea after oral "1"5N-glycine administration. Myofibrillar protein breakdown was estimated from urinary 3-methyl-histidine. Dietary protein had no effect on turnover rates, even when N balance was negative. Whole body protein synthesis was 3.60+/-0.12 g/kg.day and breakdown was 3.40+/-0.14 g/kg.day for all N intakes. Whole body ...
Programmed cell death (PCD) is triggered when Pto, a Ser-Thr protein kinase, recognizes either the AvrPto or AvrPtoB effector from Pseudomonas syringae pv tomato. This...Full Text Available
In higher plants, three subfamilies of sucrose nonfermenting-1 (Snf1)-related protein kinases have evolved. While the Snf1-related protein kinase 1 (SnRK1) subfamily has been shown to share pivotal...Full Text Available
Scyl1 is an evolutionarily conserved N-terminal protein kinase-like domain protein that plays a role in COP1-mediated retrograde protein trafficking in mammalian cells. Furthermore, loss of Scyl1 function...Full Text Available
This study investigated relationships between molecular weight distributions of unreduced grain proteins and grain, flour, and end-use quality characteristics of soft white winter wheats grown in Oregon. Absorbance area and area % values of protein fractions separated by size exclusion HPLC (SE-HPL...
CAP18 (an 18-kDa cationic antimicrobial protein) is a granulocyte-derived protein that can bind lipopolysaccharide (LPS) and inhibit various activities of LPS in vitro. The present study examined the...Full Text Available
The discovery of a specific high-affinity growth hormone (GH) binding protein (GH-BP) in plasma adds complexity to the dynamics of GH secretion and clearance. Intuitive predictions are that such a protein...Full Text Available
We have identified another Drosophila GTP-binding protein (G protein) alpha subunit, dGq alpha-3. Transcripts encoding dGq alpha-3 are derived from alternative splicing of the dGq alpha locus previously...Full Text Available
Gamma interferon plays an important role in regulating the functional properties of mononuclear phagocytes. In the present study, the role of activated protein kinases in the mechanism of action of...Full Text Available
Zn2+-finger proteins comprise one of the largest protein superfamilies with diverse biological functions. The ATM substrate Chk2-interacting Zn2+-finger protein...Full Text Available
The major core protein (p28) of MMC-1, an endogenous type C virus of the rhesus monkey (Macaca mulatta), was purified and subjected to structural and immunological analyses. The NH2-terminal amino acid...Full Text Available
The interaction of intense, sub-picosecond laser pulses with solid targets produces intense picosecond x-ray pulses. With focused laser pulses of several 10 {sup 18} W/cm{sup 2}, He-like and H-like line radiation from targets such as aluminum and silicon has been produced. The energy conversion efficiency from the laser pulse energy to the 1--2 keV line x-rays is nearly one percent. The duration of the line x-ray radiation is of the order of ten picoseconds, although this may be an upper estimate because of the temporal resolution of the x-ray streak camera. The spatial extent of the x-ray source region is only slightly larger than the laser focal spot, or about 10 {mu}m in diameter. With these characteristics, such x-ray sources emit an intensity of nearly 10{sup 14} W/cm{sup 2}. Experiments and modeling which led to the above conclusions will be discussed.
The alloying of steel surface with aluminum (Al) using Microsecond-pulsed Intense Electron Beams (MIEB-Al) was developed and optimized in order to be used for improving the corrosion resistance of the 316, 1.4970 and T91 steels, exposed to liquid Pb and Pb-Bi-eutectic. The procedure consists in two steps: (i) coating the steel surface with Al or an Al-containing alloy layer and (ii) melting the coating layer and the steel surface layer using intense pulsed electron beam. In order to cover the steel surface with an homogeneous and crack-free Al-alloyed layer, the following experimental conditions are required: Al coating thickness range 5-10mm, electron kinetic energy 120keV; pulse duration 30ms; energy density 40-45J/cm2; number of pulses 2-3. Using the mentioned procedure, the corrosion r...
We present computer modeling along with experimental data on the formation of sharp conical tips on silicon-based three-layer structures that consist of a single-crystal Si layer on a 1 {mu}m layer of silica on a bulk Si substrate. The upper Si layers with thicknesses in the range of 0.8-4.1 {mu}m were irradiated by single pulses from a KrF excimer laser focused onto a spot several micrometers in diameter. The computer simulation includes two-dimensional time-dependent heat transfer and phase transformations in Si films that result from the laser irradiation (the Stefan problem). After the laser pulse, the molten material self-cools and resolidifies, forming a sharp conical structure, the height of which can exceed 1 {mu}m depending on the irradiation conditions. We also performed computer simulations for experiments involving single-pulse irradiation of bulk silicon, reported by other groups. We discuss conditions under ...
In the microwave tokamak experiment (MTX) program, we are concentrating on experiments using intense, free-electron laser (FEL) generated microwave pulses. In initial FEL experiments, several diagnostic instruments were operated during injection of microwave pulses with peak powers to 0.2 GW at durations of 10 ns. Fixed and spatially scanning microwave detectors and receivers and a 48-element calorimeter on the inside wall of MTX diagnosed the GW-level FEL microwave pulses. With these diagnostics, linear-wave absorption and efficiencies of transmission through the quasi-optical transport system were studied. In addition, several radially resolved measurements of plasma density, temperature, and emission were made during FEL injection and were used in the analysis of microwave absorption data. A timing system, slaved to the FEL pulse arrival time, is capable of accuracy to a few nanoseconds in order to ...
This work aims at improving the understanding of the dynamics of a Free Electron Laser (FEL) based on a storage ring. A new phenomenon of saturation by the electron bunch transverse dimensions is pointed out, during the FEL operation with a magnetic optics ''low emittance''. A part of this thesis work concerns the study of the longitudinal dynamics of the FEL depending on a parameter: the detuning between the pass frequency of the electrons and the back and return frequency of the laser pulse in the optical cavity. This study shows that the FEL presents a pulsed or a steady state behavior depending on the detuning. Besides, a spectro-temporal behavior of the FEL is pointed out showing the FEL pulse substructures and holes in the spectrum. Another part of this work concerns the response of the resonant FEL system, when a perturbation is applied on the gain. Under the effect of a modulation, the FEL can present a periodic or ...
Production of ozone and OH radical is required to advance the plasma chemical reactions in the NOx removal processes for combustion gas treatment. The corona discharge to the water surface is expected to induce the good conditions for the proceeding of the NO oxidation and the NO_2 dissolution removal into water. In order to get the fundamental data of the corona discharge over the water surface, the positive and negative V-I characteristics and the ozone production were measured with the multi needle and the saw-edge type of the discharge electrodes. The pulse corona characteristics were also measured with some different waveforms of the applied pulse voltage. The experiments were carried out under the atmospheric pressure and room temperature. Both the DC and the pulse corona to the water surface showed a stable and almost the same V-I characteristics as to plate electrodes though the surface of water was waved by corona ...
Up to now the long range filaments have been considered as a balance between Kerr focusing and defocusing by plasma generation in the nonlinear focus. However, it is difficult to apply the above explanation of filamentation in far-field zone. There are basically two main characteristics which remain the same at these distances - the super broad spectrum and the width of the core, while the power in a stable filament drops to the critical value for self-focusing. At such power the plasma and higher-order Kerr terms are too small to prevent self-focusing. We suggest here a new mechanism for stable soliton pulse propagation in far-away zone, where the power of the laser pulse is slightly above the critical one, and the pulse comprises super-broad spectra. For such pulses the diffraction is not paraxial and an initially symmetric Gaussian pulse takes parabolic form at several ...
We have studied freshly prepared lysozyme solutions in heavy water for two NaCl concentrations as a function of temperature. Lysozyme solubilities in this solvent are determined by static light scattering. By small angle neutron scattering, we evidence that interactions between lysozyme molecules are characterized by a second virial coefficient A{sub 2} whether the solution is under-saturated or supersaturated. From the variation of A{sub 2} as a function of temperature we have evaluated the enthalpy corresponding to the interaction between lysozyme molecules. We show that the interactions between protein molecules are higher in heavy water than in light water. (authors). 13 refs., 3 figs.
It is a useful hypothesis to thing of the reaction to protein deprivation as made up of two parts. First there is an initial adaptation involving rapid losses of protein. This is followed by slow continuing depletion. When considering two organ groups, such as the liver and muscle, it appears that the curve of urinary nitrogen excretion reflects the different parts they play in these two phases. The changes in the relative amounts of protein in different organs results in an alteration in the pattern of body protein at the level of the organ, the tissue and the cell. These changes are themselves the result of altered rates of synthesis and breakdown. The questions that must be asked and hopefully will be answered with the help of isotopes, are how these changes are brought about, how they are inter-related and controlled, and what is their significance? This paper contains a discussion of the few ...
The green fluorescent protein (GFP) asFP499 from Anemonia sulcata is a distant homologue of the GFP from Aequorea victoria. We cloned the asFP499 gene into a mammalian expression vector and showed that this protein was expressed in the human lymphoblast cell line Ramos RA1 and in the embryonic kidney 293T cell line (HEK 293T). In HEK 293T cells, asFP499 was localized mainly in the cytoplasm, suggesting that the protein was excluded from the nucleus. We identified _1_9_4LRMEKLNI_2_0_1 as a candidate nuclear export signal in asFP499 and mutated the isoleucine at position 201 to an alanine. Unlike the wildtype form, the mutant protein was distributed throughout the cytoplasm and nucleus. This is First report of a GFP that contains a functional NES.
Frozen boiled shrimp and dried shrimp are among the high-value fishery products of Thailand. During the production of these products boiling is one of the most important steps that affects significantly the product physicochemical properties, especially the quantity and quality of proteins, which in turn affect other apparent properties perceived by consumers. The protein changes are, however, difficult to evaluate comparing to other typical physical properties of shrimp. The objective of this study was therefore to develop an artificial neural network (ANN) model to predict the protein changes of shrimp in terms of protein loss and protein denaturation as a function of the boiling conditions, namely, concentration of salt solution and boiling time, as well as a rather easily determined ch...
It is assumed that protein fibrils manifested in amyloidosis result from an aggregation reaction involving small misfolded protein sequences being in an `oligomeric' or `prefibrillar' state. This review covers recent optical spectroscopic studies of amyloid protein misfolding, oligomerization and amyloid fibril growth. Although amyloid fibrils have been studied using established protein-characterization techniques throughout the years, their oligomeric precursor states require sensitive detection in real-time. Here, fluorescent staining is commonly performed using thioflavin T and other small fluorescent molecules such as 4-(dicyanovinyl)- julolidine and 1-amino-8-naphtalene sulphonate that have high affinity to hydrophobic patches. Thus, populated oligomeric intermediates and related `pre...
The effect of experimental diabetes on the phosphorylation of proteins in the rat sciatic nerve was studied. Nerves from animals made diabetic with streptozocin were incubated in vitro with (/sup 32/P)orthophosphate and divided into segments from the proximal to the distal end, and proteins from each segment were then separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The principal labeled species were the major myelin proteins, P0, and the basic proteins. After 6 wk of diabetes, the incorporation of isotope into these proteins rose as a function of distance along the nerve in a proximal to distal direction and was significantly higher at the distal end compared with incorporation into nerves from age-matched controls. The overall level of isotope uptake was similar in nerves from diabetic animals and weight-matched controls. The distribution of /sup 32/P among ...
The purpose of the present study was to examine the in vitro effects of low-dose cadmium (Cd) on developing cortical cells. The cortical cells removed from fetuses (embryonic day 15) were treated with 10 nM of Cd for 24 h. The effects of Cd on dendritic and synaptic development were immunocytochemically observed with anti-microtubule associated protein-2 (MAP2) and anti-synapsin I antibodies, respectively. Administration of Cd suppressed dendritic as well as synaptic development at 10 nM. By two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometric (LC/MS/MS) analysis, we identified three proteins with different expression after Cd-treatment; dihydropyrimidinase-related protein 2 (DRP-2/CRMP-2), 14-3-3-epsillon and calmodulin (CaM). Though the number of identified proteins was small, these proteins are known to be involved in neuronal development. The ...
Pulses are rich in nutrients. The existence of anti-nutritional components and the length of time required for preparation have, however, limited their frequency of use compared to recommended intake levels. Anti-nutritional components in pulses can be largely removed by heat treatment. Additionally pre-treatment of pulses with heat and processing of seeds into flour could further enhance their use by decreasing processing and preparation times. In this study, trypsin inhibitor activity, functional properties, and microstructural characteristics of flours prepared from different varieties of lentil, chickpea, and pea as affected by roasting and boiling were evaluated. Both thermal treatments resulted in significant reduction (p<0.05) in trypsin inhibitor activity ranging from -95.6% to -37...
Improved biosorption of uranium by Kluyveromyces marxianus IMB3 biomass was achieved by increasing the electric field strength of delivered pulses from 1.25kV/cm to 2.5kV/cm. Although this had little or no effect on the maximum biosorption capacity (q(max)), at low concentrations of uranium the amount bound to the biomass increased from 70 to 140mg uranium/g biomass. Significant increases in the maximum biosorption capacities (119-180 mg uranium/g biomass) were observed when the pulse field strength was increased from 2.5kV/cm to 3.25kV/cm. (Author).
The production of retrograde amnesia (RA) upon electron-beam exposure was investigated. RA production was evaluated using a single-trial avoidance task for 10, 1, and 0.1 microsecond pulsed exposures. The dose-response curve obtained at each pulse duration showed significant RA production. The most effective dose range was 0.1-10 rad at a dose rate of 1,000,000 rad/sec. By employing a 10 rad (1,000,000 rad/s) pulse, a memory loss of the events occurring in the previous 4 sec was demonstrated. The conclusion was that the RA effect might be due to sensory system activation which provided a novel stimulus that masked previous stimuli.
The goal of this research program is to determine whether pulsed laser deposition is an effective alternative method for growing TiCN thin films. Pulsed laser deposition (PLD) is chosen because of its well-documented capability for growing uniform, stoichiometric films in ultra-high vacuum or gaseous environments. Processing of thin films by PLD is also achieved at relatively low temperatures compared with CVD processing. Given these attributes, the primary objectives in this article are to determine whether nitrogen may be readily incorporated into films resulting from the laser-ablation of TiC in an N{sub 2} environment, determine what effect nitrogen has on mechanical properties, and determine whether nitrogen incorporation is strongly influenced by processes unrelated to laser deposition (e.g., thermally-activated surface reactions).
The Pulsed Lepton Source (PLS) project opens some exciting possibilities for muon and neutrino physics . The PLS would use the 0.25 4s proton pulses from the upgraded Proton Storage Ring (PSR) at LAMPF to create short, intense bursts of muons and neutrinos. The neutrino beam would be used for a few fundamentally important weak interaction physics experiments. The muon beams would find a wide variety of applications in both fundamental and applied'' muon physics areas. After a brief discussion of the physical layouts of the PSR and the proposed PLS in Sec. 2 and muon area in Sec. 3, we note some of the muon physics experiments and areas that could advantageously be addressed at the PLS in Secs. 4 and 5, and conclude in Sec. 6.
The major bottleneck for popularization and utilization of the conventional mechanical valve pulse combustors is the self-priming mode of gas supply. An aerodynamic valve (as against mechanical valve) self-excited pulse combustor of the Helmholtz-type with continuous supply of gas and air was designed and a mathematical model was established in this paper. The theoretical model employed well-stirred reactor model and a single step Arrhenius chemistry, and took those factors which might affect the combustion stability into account. The factors include the variation of the mass rate of the reactants affected by the pressure in the combustion chamber, the convective and radiation heat loss in the combustion chamber, and the heat transfer and wall friction in the tailpipe. The effect of wall t...
Conductive TiN/Si_3N_4 ceramic composites were processed by electrical discharge machining (EDM) and their microstructure and conductivity were investigated. The whole process of tool electrode wear is evaluated by sinker-EDM. The machined surfaces of TiN/Si_3N_4 ceramic composites were examined by scanning electron microscopy (SEM) and profilometry to determine the surface finish. The electrode wear rate of brass is higher than copper electrode for all EDMed tests. The surface texture was found to have greater dependence on pulse energy. It was observed that the sinker-EDM at higher pulse energy caused severe microdamage in the surface. The surface roughness (Ra) values also increase with increasing pulse energy.
Ferroelectric disks, coated with proper electrodes, can easily produce a dense plasma cloud when excited with a high-voltage pulse. This plasma can be a source of either electrons or ions depending on the sign of the extracting field set in front of the disk. We present the behavior of the disks operating at high frequency as emitters of both electrons and ions in two experimental configurations: (a) without and (b) with two screening grids. These two screening grids are inserted when the plasma must be confined within the cathode region. The system is capable of providing ion pulses of a few hundred milliamperes, whose length can range from a hundred nanoseconds to dozen microseconds. The electron pulses of energetic electrons have typically an amplitude higher than a couple of amperes. Tests at MHz repetition rate were positive as for stable operation.
The nature of the `inner engine' that accelerate and collimate the relativistic flow at the cores of GRBs is the most interesting current puzzle concerning GRBs. Numerical simulations have shown that the internal shocks' light curve reflects the activity of this inner engine. Using a simple analytic toy model we clarify the relations between the observed $ \\gamma $-rays light curve and the inner engine's activity and the dependence of the light curves on the inner engine's parameters. This simple model also explains the observed similarity between the observed distributions of pulses widths and the intervals between pulses and the correlation between the width of a pulse and the length of the preceding interval. Our analysis suggests that the variability in the wind's Lorentz factors arises due to a modulation of the mass injected into a constant energy flow.
We propose and analyze a novel regenerative amplifier free electron laser (FEL) to produce fully coherent x-ray pulses. The method makes use of narrow-bandwidth Bragg crystals to form an x-ray feedback loop around a relatively short undulator. Self-amplified spontaneous emission (SASE) from the leading electron bunch in a bunch train is spectrally filtered by the Bragg reflectors and is brought back to the beginning of the undulator to interact repeatedly with subsequent bunches in the bunch train. The FEL interaction with these short bunches not only amplifies the radiation intensity but also broadens its spectrum, allowing for effective transmission of the x-rays outside the crystal bandwidth. The spectral brightness of these x-ray pulses is about two to three orders of magnitude higher than that from a single-pass SASE FEL.
A design of a compact free-electron laser (FEL), generating ultra-fast, high-peak flux, XUV pulses is presented. The FEL is driven by ahigh-current, 0.5 GeV electron beam from the Lawrence Berkeley National Laboratory (LBNL) laser-plasma accelerator, whose active acceleration length is only a few centimeters. The proposed ultra-fast source (~;;10 fs) would be intrinsically temporally synchronized to the drive laser pulse, enabling pump-probe studies in ultra-fast science. Owing to the high current (>10 kA) of the laser-plasma-accelerated electron beams, saturated output fluxes are potentially greater than 10^13 photons/pulse. Devices based both on self-amplified spontaneous emission and high-harmonic generated input seeds, to reduce undulator length and fluctuations, are considered.
One of the more extensive uses of directional drilling anywhere in the world has been in the development of the East Wilmington Oil Field in Long Beach, California. The Measurement-While-Drilling (MWD) directional system has been tested on several wells and proven to provide the required accuracy, along with many advantages over past methods, used in the field development. Accurate transmission by MWD of bottom-hole measurements to the surface is provided by mud pressure pulses generated in the drill pipe downhole and detected by a pressure transducer includes the means for detecting, recording and processing these pressure pulses, to translate the information from the pressure pulses to rig floor displays usable by the drilling crew. 2 refs.
A pillbox RF output window was developed for the L-band pulsed klystron for the Japanese Hadron Project (JHP) 1-GeV proton linac. The window was designed to withstand a peak RF power of 6 MW, where the pulse width is 600 {mu}sec and the repetition rate is 50 Hz. A high power model was fabricated using an alumina ceramic which has a low loss tangent of 2.5x10{sup -5}. A high power test was successfully performed up to a 113 kW RF average power with a 4 MW peak power, a 565 {mu}sec pulse width and a 50 Hz repetition rate. By extrapolating the data of this high power test, the temperature rise of the ceramic is estimated low enough at the full RF power of 6 MW. Thus this RF window is expected to satisfy the specifications of the L-band Klystron. (author).
A voice activated garage door opener was designed for a handicapped person to open a garage door without assistance. This design uses speech recognition of one word. The activating word that was chosen is "up". The frequency spectrum of "up" was captured on a soundboard and is the basis of this design. Filters are used to pick out three frequency bands in this spectrum. The output signals from these filters are then compared to three threshold voltages using voltage comparators. If the output signals from the filters are above the threshold voltages, the comparators go high. Monostable multivibrators are used on the output of the comparators to lengthen the high pulses. When all of the pulses from the monostable multivibrators are high at the same time, an AND gate output goes high. This high pulse activates the door opener. PMID:8329601
The design and operating principle of a small (50 mm in diameter and 100 mm in height) ???-73C vacuum spark gap are described. It is shown that it can be efficiently switched using a control circuit with a low (?900 V) supply voltage, which is based on an inductive energy storage and a diode opening switch that forms a high-voltage igniting pulse with a rise time of nanosecond duration. The ???-73C switching process is investigated at different rise times of igniting voltage pulses and different igniting current amplitudes. The results of tests of the spark gap operating in regimes of switching current pulses with an amplitude of 12 kA and a rise time of 800 ns are presented.
This paper describes the specifications, conceptual design, prototype testing and operating experience of an oil-filled high voltage pulse transmission cable adapted from commercially available air-dielectric RF components. Lawrence Livermore National Laboratory's Advanced Test Accelerator (ATA) requires a method of transmitting 250kV, 70 nanosecond pulses from the power conditioning equipment to the accelerator. The oil-filled cable approach was chosen over alternative concepts because of its high voltage holding capacity, long life and flexibility. The criteria for cable and connector design are discussed. The results of prototype testing and performance of the final design are presented.
One of the main challenges for a high energy {gamma}{gamma} collider is the high repetition rate required for the laser-electron-beam collisions to convert into high energy gamma beams. State-of-the-art, high power lasers have a much lower repetition rate than that of the electron pulses. It is therefore highly desirable that the same laser pulse can be reused. As an example, for NLC where beams collide at 120 Hz, within each collision cycle there are 90 electron bunches separated by 1.4 ns between successive bunches. We show, by invoking a recently invented laser optical box, that the laser pulses can be reused for the entire train of bunches within each collision cycle. ((orig.)).
One of the main challenges for a high energy #gamma##gamma# collider is the high repetition rate required for the laser-electron-beam collisions to convert into high energy gamma beams. State-of-the-art, high power lasers have a much lower repetition rate than that of the electron pulses. It is therefore highly desirable that the same laser pulse can be reused. As an example, for NLC where beams collide at 120 Hz, within each collision cycle there are 90 electron bunches separated by 1.4 ns between successive bunches. We show, by invoking a recently invented laser optical box, that the laser pulses can be reused for the entire train of bunches within each collision cycle. ((orig.)).
A high sensitivity, high bandwidth, two-color interferometer (1064 and 532 nm) has been tested on the Hawk pulsed power generator at the Naval Research Laboratory. The phase resolution is 10"-"5 waves with a rise time of 3 ns, a new capability for diagnosing plasmas, and neutrals in pulsed power experiments. The two-color feature is used to distinguish phase shifts from free (plasma) electrons and bound (neutral and ion) electrons. Simultaneous electron and neutral density measurements were demonstrated in a plasma opening switch (POS) experiment. The ability to measure small phase shifts with fast rise time were demonstrated in a plasma filled diode experiment. The high sensitivity and vibration isolation enable neutral gas distribution measurements from supersonic nozzles used in plasma radiation source experiments. Examples of these measurements and future applications are described. copyright 1997 American Institute of Physics.
The entrapment of proteins using the sol-gel route provides a means to retain its native properties and artificially reproduce the molecular crowding and confinement experienced by proteins in the cell allowing investigation of the physico-chemical and structural properties of biomolecules at the biotic/abiotic interface. The biomolecules are spatially separated and 'caged' in the gel structure but solutes can freely permeate the matrix. Thus, properties such as the folding of ensembles of individual molecules can be examined in the absence of aggregation effects that can occur in solution studies. Green fluorescent protein from Aequorea coerulescens was used as a model protein to examine the unfolding/re-folding properties of protein in silica gels. The recombinant protein was isolated and purified from Escherichia coli extracts by cell lysis, ...
In previous work the authors showed that on photolysis of Escherichia coli ribosomes in the presence of ({sup 3}H)tetracycline (TC) the major protein labeled is S7, and they presented strong evidence that such labeling takes place from a high-affinity site related to the inhibitory action of TC. In this work they use single protein omission reconstitution (SPORE) experiments to identify those proteins that are important for high-affinity TC binding to the 30S subunit, as measured by both cosedimentation and filter binding assays. With respect to both sedimentation coefficients and relative Phe-tRNA{sup Phe} binding, the properties of the SPORE particles they obtain parallel very closely those measured earlier, with the exception of the SPORE particle lacking S13. A total of five proteins, S3, S7, S8, S14, and S19, are shown to be important for TC binding, with the largest effects seen on omission of ...
Haemangiomas usually develop within the first few weeks of life, most regressing spontaneously before the age of 7 years. Some may ulcerate or compromise a vital function, in which case systemic corticosteroids, surgery or radiotherapy may be helpful. All of these treatment modalities are associated with significant morbidity. Treatment with the 585 nm flashlamp pulsed dye laser is safe and effective in the management of superficial vascular malformations. We report seven patients, under 12 months of age, who presented with proliferative haemangiomas, causing functional impairment. Ulcerated lesions were present in four patients. The patients were treated with the 585 nm pulsed dye laser (fluences 7.0-9.25 J/cm2), at intervals of 4-8 weeks. All of the lesions showed a significant reduction in size, together with improvement in the colour and integrity of the overlying skin. Treatment with the 585 nm pulsed dye laser should ...
Using standard brass alloy samples, an approach to reduce the laser-induced breakdown spectroscopy measurement uncertainty was tested and proved. Two important parameters for plasma characterization, the plasma temperature and the electron density, were applied to minimize the signal uncertainties due to uncontrollable experimental parameter variations. Results show that for the pulse-to-pulse analysis, the signal fluctuations can be significantly reduced by utilizing the plasma characteristic information. The major source for the single pulse fluctuations is the redistribution of the characteristic line at different temperatures according to the Boltzmann distribution under LTE. The change of the degree of ionization also contributes to the signal fluctuations. For the multi-pulse analysis, due to the nonlinear relationship between the plasma temperature and the line intensity, it is not applicable to utilize the Boltzmann ...
Analysis of the pulsed-field gel electrophoretic profiles of 82 pneumococcal isolates with reduced susceptibility to ciprofloxacin (RSC) and of 90 co-occurring susceptible isolates indicates a considerable...Full Text Available
In systems of fast decimal counters, there are three problems to be resolved: to study a bistable having a short switching time, to form with the aid of three bistables a circuit divisible by 5, and to normalize the input pulses. The solutions to these problems for the nonsecond scaler are presented. (J.S.R.)
The automatic real-time system operating at the LU-10 linac and providing measurements of the parameters such as the beam current (average and pulse values), the electron energy, the linear density distribution of beam current, and also the conveyor speed is described in the paper.
High pressure xenon ionization chamber detectors are possible alternatives to traditional thallium doped sodium iodide (NaI(Tl)) and hyperpure germanium as gamma spectrometers in certain applications. Xenon detectors incorporating a Frisch grid exhibit energy resolutions comparable to cadmium/zinc/telluride (CZT) (e.g. 2% (at) 662keV) but with far greater sensitive volumes. The Frisch grid reduces the position dependence of the anode pulse risetimes, but it also increases the detector vibration sensitivity, anode capacitance, voltage requirements and mechanical complexity. We have been investigating the possibility of eliminating the grid electrode in high-pressure xenon detectors and preserving the high energy resolution using electronic risetime compensation methods. A two-electrode cylindrical high pressure xenon gamma detector coupled to time-to-amplitude conversion electronics was used to characterize the pulse rise time of deposited gamma ...
Technologies for materials, processes, and manufacturing that will provide safe, .... advanced energy conversion techniques, and pulsed inductive and ... duration antimatter storage and transportation, and methods for utilizing ...... EVA systems can be found in the EVA Technology Roadmap of the EVA Project Plan. ...
The paper briefly describes the nuclear reactor facilities at Sandia Laboratories which are used for simulating nuclear weapon produced neutron environments. These reactor facilities are used principally in support of continuing R and D programs for the Department of Energy/Office of Military Application (DOE/OMA) in studying the effects of radiation on nuclear weapon systems and components. As such, the reactors are available to DOE and DOD agencies and their contractors responsible for the radiation hardening of advanced nuclear weapon systems. Emphasis is placed upon two new reactor simulation sources; the Sandia Pulse Reactor-III (SPR-III) Facility which enhances the neutron exposure volume capabilities over those presently available with the existing SPR-II Facility, and the Upgraded Annular Core Pulse Reactor (ACPR) Facility which enhances the neutron exposure capabilities over those of the former ACPR Facility.
The traveling-wave mode in ring lasers is achieved by two methods: by a reversing mirror, and by using an intracavity nonreciprocal device. This paper is devoted to realization of the traveling-wave mode in a mode-locked YAG-Nd ring laser by a method proposed by Tomov et al. This method uses two intracavity Q-switches. In mode-locked operation, pulses are generated that can be considered short compared with the period of modulation T = L/C (where L is the length of the perimeter of the cavity). Analysis shows that if the shift of the switching signals corresponds to the time of travel of a light pulse between Q-switches, the pulse in one direction will pass the Q-switches at instants of zero losses, while losses in the other direction will be maximized for a distance between Q-switches of L/4, and will be zero for a distance L/2. Experimental verification of the proposed method gave unidirectional lasing with an intensity ...
The cosmic ray neutron spectrum at sea level has been measured by the method of pulse shape discrimination in anthracene scintillator. The exponent of the differential spectrum was found to be 2.2+-0.1. (Auth.).
A case of {beta}-thalassemia intermedia with spinal cord compression due to extramedullary hematopoiesis, which was successfully treated by blood transfusion, is presented. Emphasis was made on the MRI appearance of extramedullary hematopoiesis on different pulse sequences. The theories that aimed to explain the involvement of the epidural space by extramedullary hematopoiesis are discussed.
twenty 350 V, 2.5 mF aluminum electrolytic capacitors with 10.8 mH inductors made of multi-strand wire. The PFN discharge was controlled using an silicon ...
The major activities of the various Institute's departments are highlighted. The following departments are included: (i) Tokamak; (ii) Pulse plasma systems; (iii) Thermal plasma; (iv) Materials engineering; (v) Laser plasma; and (vi) Optical diagnosis. (P.A.)
The photon rupture method, by which oxide film and metal are removed by focused pulsed Nd-YAG laser beam irradiation, was applied to form artificial micro-pits in Zn-5 mass% Al alloy-coated steel. The zinc alloy-coated layer was removed by pulsed laser irradiation treatment for about one second in a neutral buffer solution with NaCl. The rest potential transient with the laser treatment was measured. In the early stage of the laser treatment the rest potential of zinc alloy-coated steel changed to the negative direction immediately after every irradiation of a laser pulse and then returned to the previous value. However, after the steel substrate was exposed to the solution, the rest potential moved to the positive direction immediately after every irradiation of a laser pulse and then returned to the previous value. The amplitude and duration of the potential change after the laser irradiation ...
The use of dendritic cells (DCs) as a cellular adjuvant is a promising approach to the immunotherapy of cancer. It has previously been demonstrated that DCs pulsed ex vivo with Toxoplasma gondii...Full Text Available
Naturally occurring and contaminant ferromagnetic and ferrimagnetic particles have been found within or near cells, and might allow pulsed magnetic fields to create transient cell membrane opening ("pores")....Full Text Available
First structural wall material (FSW) materials in inertial fusion energy (IFE) power reactors will be irradiated under typical repetition rates of 1-10 Hz, for an operation time as long as the total reactor lifetime. The main objective of the present work is to determine whether a continuous-pulsed (CP) approach can be an efficient method in modeling the pulsed activation process for operating conditions of FSW materials. The accuracy and practicability of this method was investigated both analytically and (for reaction/decay chains of two and three nuclides) by computational simulation. It was found that CP modeling is an accurate and practical method for calculating the neutron-activation of FSW materials. Its use is recommended instead of the equivalent steady-state method or the exact pulsed modeling. Moreover, the applicability of this method to components of an IFE power plant subject to repetition rates lower than ...
The longitudinal and transverse dynamics of a heavy ion fusion beam during the drift compression and final focus phase is studied. A lattice design with four time-dependent magnets is described that focuses the entire beam pulse onto a single focal point with the same spot size.
The most important developments in gaseous detectors at LNL are reviewed. Some aspects of timing, pulse height and position resolutions of avalanche counters are reported. The experimental work on heavy-ion identification by Bragg curve spectroscopy is summarized.
Normal reproductive functioning may require secretion of LH independently of FSH. Variation in GnRH pulse frequency and inhibin negative feedback are mechanisms for differential gonadotropin regulation;...Full Text Available
Atomic oxygen is measured in a pulsed dielectric barrier discharge (DBD) using two-photon absorption laser-induced fluorescence (TALIF). The ground-level atomic oxygen is excited to the 3p "3P state by two-photon absorption at 226 nm. Negative (-40 kV) or positive (+30 kV) pulsed DBD occurs in an O_2-N_2 mixture at atmospheric pressure. The pulse width of the DBD current is approximately 50 ns. The TALIF experiment shows that the decay rate of atomic oxygen increases linearly with O_2 concentration. This result proves that atomic oxygen decays mainly by the third-body reaction, O + O_2 + M #-># O_3 + M. The rate coefficient of the third-body reaction is estimated to be 2.2 x 10"-"3"4 cm"6 s"-"1 in the negative DBD and 0.89 x 10"-"3"4 cm"6 s"-"1 in the positive DBD. It is shown that the decay rate of atomic oxygen increases linearly with humidity. This can explain the well-known fact that ozone production in DBD is ...
A technique of low-field pulsed proton nuclear magnetic resonance (NMR) spin relaxation is described for assessment of age-related structural changes (dentin and pulp) of human teeth in...Full Text Available
In a mass casualty situation, medical personnel at the disaster site and other field treatment settings may need to monitor the vital signs of hundreds of seriously injured patients with minimal staffing....Full Text Available
The effects of thiol-specific reagents on the amplitude of the electro-olfactogram (E.O.G.) responses elicited from frog olfactory mucosa by pulses of odorant vapours was studied. The impermeant thiol-specific...Full Text Available
Significant progress has been achieved recently in the growth of Yttrium Calcium Oxyborate (YCOB) crystals. Boules have been grown capable of producing large aperture nonlinear crystal plates suitable for high average power frequency conversion or optical parametric chirped pulse amplification (OPCPA). With a large aperture (5.5 cm x 8.5 cm) YCOB crystal we have demonstrated a record 227 W of 523.5nm light (22.7 J/pulse, 10 Hz, 14 ns). We have also demonstrated the applicability of YCOB for 1053 nm OPCPA.
This paper reports on the results of experiments into efficient higher-order anti-Stokes Raman conversion of tunable short-pulse XeCl laser radiation. The maximum output energy of the pumping laser, in which the radiation of a frequency-doubled dye laser is amplified by two XeCl laser amplifiers, is 55 mJ with a pulse duration of 1 ns FWHM. Using hydrogen gas as a Raman medium, a series of anti-Stokes lines up to the 12th order (121.5 nm) is generated in the vacuum ultraviolet (VUV) region. 16 references.
Lupus pernio of the nose is the most characteristic cutaneous lesion of sarcoidosis. It is cosmetically disfiguring and can be the cause of significant morbidity. In particular, the affected skin is often red or purple due to increased vasculature. It is particularly resistant to both surgical and medical therapy. We describe a patient with lupus pernio affecting her nose, which showed a dramatic improvement following treatment with the pulse dye laser (PDL). A biopsy taken after treatment showed the continued presence of sarcoidal granulomas. We therefore feel that treatment with the PDL is an effective tool in improving the cosmetic appearance of lupus pernio, but does not influence the underlying disease process. PMID:11360426
Superconducting magnetic and inertial energy pulsed power systems are being developed for future theta-pinch, Tokamak, and laser fusion applications. The short term requirements for these applications are discussed along with present day accomplishments. Areas requiring a research and development effort are examined in detail. Subjects discussed include stresses, energy loss factors, conductor metallurgy, cryogenic requirements, and electrical limitations of superconducting magnetic storage systems; costs, applications, and present technology of homopolar systems; and switching problems associated with both systems.
Tests for the applicability of a CFD (Computational Fluid Dynamics) code for simulating activity transport in PNA (Pulsed Neutron Activation) fluid measurements have been performed. The CFD code was combined with a Monte Carlo code used for the calculation of the initial activity distribution. The results from the calculations show that it is possible to use CFD for calculation of the activity distribution in PNA. The mainly qualitative results in this work are encouraging and suggest further work. In the continuation of this work a response function for the gamma detector will be calculated so that a PNA time spectrum can be simulated. A more accurate comparison with experimental data can then be performed
The paper presents results of experimental research on the interaction of a pulsed plasma-ion stream with a tungsten (W) target. The pulsed hydrogen plasma was produced within the RPI-IBIS (Multi-Rod Plasma Injector) facility at IPJ in Swierk. Measurements were carried out by means of optical spectroscopy and corpuscular diagnostic techniques. For experiments with the W-target the operational conditions (so-called PID mode) were chosen when a clean hydrogen plasma stream was generated. Attention was paid to the identification of WI and WII spectral lines.
Processing techniques utilizing low temperature depositions and pulsed lasers allow the fabrication of polysilicon thin film transistors (TFT`s) on plastic substrates. By limiting the silicon, SiO2, and aluminum deposition temperatures to 100(degrees)C, and by using pulsed laser crystallization and doping of the silicon, we have demonstrated functioning polysilicon TFT`s fabricated on polyester substrates with channel mobilities of up to 7.5 cm2/V-sec and Ion/Ioff current ratios of up to 1x10(to the 6th power).
In situ optical absorption spectroscopy was used to study the generation of E' centres in amorphous SiO_2 occurring by photo-induced breaking of Si-H groups under 4.7eV pulsed laser radiation. The dependence from laser intensity of the defect generation rate is consistent with a two-photon mechanism for Si-H rupture, while the growth and the saturation of the defects are conditioned by their concurrent annealing due to reaction with mobile hydrogen arising from the same precursor. A rate equation is proposed to model the kinetics of the defects and tested on experimental data.
The ability of the Packard 2000 CA/LL liquid scintillation counter to reduce background count rates relies on pulse shape/duration analysis in which short duration organic scintillation events are discriminated from longer duration non-quenchable background events. A consequence of this is a loss in the counting efficiency. The results of this investigation indicate that much of the lost efficiency can be regained by sharpening the true #beta#"- pulse widths via the use of different scintillant combinations and by certain counter modifications. (author).
We are investigating a novel insulator concept which involves the use of alternating layers of conductors and insulators with periods less than 1 mm. These structures perform many times better (about 1.5 to 4 times higher breakdown electric field) than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present our ongoing studies investigating the degradation of the breakdown electric field resulting from surface roughness, the effect of gas pressure, and the performance of the insulator structure under bi-polar stress. Further, we present our initial modeling studies.
The global effect of activation cross-section uncertainties on calculated radiological quantities is investigated for the first time using a methodology based on Monte Carlo random sampling. The method is applied to the calculation of the uncertainty in the contact dose rate from the gunite shielding of the National Ignition Facility chamber after 30 yr of pulsed irradiation. Some critical cross section contributing significantly to the overall uncertainty are identified. By a reasonable reduction of the uncertainty in those cross sections, the accuracy in the calculated total contact dose rate is greatly improved.
The grain boundary crystallographic misorientations of magnetic-pulse-welded (MPW) aluminum alloy (AA) 6061-T6 in linear and tubular configurations were examined using the electron backscattered diffraction (EBSD) technique. A refined structure of heavily deformed grains with higher grain boundary angles was observed in linear welds. Significant spalling was observed away from the joints, in the interior of tubular welds. The results show the complex interaction of shock waves with the materials during this impact welding process.
The micropulse lidar (MPL) is a ground-based optical remote sensing system designed primarily to determine the altitude of clouds overhead. The physical principle is the same as for radar. Pulses of energy are transmitted into the atmosphere; the energy scattered back to the transceiver is collected and measured as a time-resolved signal. From the time delay between each outgoing transmitted pulse and the backscattered signal, the distance to the scatterer is infered. Besides real-time detection of clouds, post-processing of the lidar return can also characterize the extent and properties of aerosol or other particle-laden regions.
Ascochyta blight causes significant yield loss in pulse crops worldwide. Integrated disease management is essential to take advantage of cultivars with partial resistance to this disease. The most effective practices, established by decades of research, use a combination of disease-free seed, destruction or avoidance of inoculum sources, manipulation of sowing dates, seed and foliar fungicides, and cultivars with improved resistance. An understanding of the pathosystems and the inter-relationship between host, pathogen and the environment is essential to be able to make correct decisions for disease control without compromising the agronomic or economic ideal. For individual pathosystems, some components of the integrated management principles may need to be given greater consideration tha...
An accelerator has limited dynamic range: a chain of accelerators is required to reach high energy. A combination of septa and kicker magnets is frequently used to inject and extract beam from each stage. The kicker magnets typically produce rectangular field pulses with fast rise- and/or fall-times, however the field strength is relatively low. To compensate for their relatively low field strength, the kicker magnets are generally combined with electromagnetic septa. The septa provide relatively strong field strength but are either DC or slow pulsed. This paper discusses injection and extraction systems with particular emphasis on the hardware required for the septa.
Two hypotheses are in the centre of this investigation, on the one hand the question, whether microwaves as exogenous fields alone are able to stimulate human muscle cells above-threshold, and on the other hand, whether microwaves as conditioning to cathodical electrical pulses can modify the excitation threshold and form. No excitation through the application of microwaves alone can be introduced at any subject. The conditioning of above-threshold cathodical electrical pulses with UMTS-microwaves leads not to a transgression of the threshold or the electrical muscle response (EMG) depending on the amplitude, the duration or the dose rate. (orig.)
An improved acousto-optic laser Q-switch uses a chirped fm pulse in the acousto-optic cell to diffract and focus the input beam into a resonating high-Q mode. When the rf acoustic pulse is not wholly within the cell, the beam is diverted to the output. A reflective surface is placed on the cell to yield only one output beam and to yield a retroflective beam back into the cavity for a high Q condition whenever a correctly generated chirp acoustic wave is in the proper postion within the cell.
Experiments are described on a plasma cathode with biased grids to prevent entry of ions into the electron extraction gap. The cathode has potential applications to the generation of high-current pulsed electron beams. Operation at 20 A/cm"2 is theoretically possible. The source combines the low average power consumption of a plasma cathode with many of the attractive features of thermionic cathodes, such as space-charge-limited extractor gap electron flow, fast turn-on, and no diode closure. Initial experiments are reported at the 2 A/cm"2 level for pulse lengths to 160 #mu#s.
Superstrong shock waves of multimegabar level generated during ablation of an aluminum surface by intense (<1 PW/cm2) femtosecond laser pulses have been detected by observing the propagation of a shock wave in air from the ablated surface to a broadband piezoelectric receiver. The estimated initial pressure and velocity of the shock wave (ablation plume) agree well with data obtained earlier by various methods for shock waves propagating inside ablated targets.
In the framework of the Low Emittance Gun (LEG) project, high gradient acceleration of a low emittance electron beam will be necessary. In order to achieve this acceleration, a -500 kV, 250 ns FWHM, pulse will be applied between two electrodes. Those electrodes should sustain the pulsed field without arcing, must not outgas and must not emit electrons. Ion back bombardment, and dark current will be damaging to the electron source as well as for the low emittance beam. Electrodes of commercially available OFE copper, aluminium, stainless steel (SS), titanium and molybdenum were tested, following different procedures including plasma glow discharge cleaning.
We have used scale models to measure the predicted coupling of electromagnetic fields simulating the effects of high-altitude nuclear electromagnetic pulses (HEMP) on the interior surfaces of electronic components. Predictive tools for exterior coupling are adequate. For interior coupling, however, such tools are in their infancy. Our methodological approach combines analytical, computational, and laboratory techniques in a complementary way to take advantage of their separate strengths. Computer models are a promising tool, as they can be used to treat complex objects with arbitrary shapes, dielectrics, and cables, and multiple apertures. Laboratory tests can expand the domain of investigation even further.
Conduction-band electrons, formed by pulse radiolysis of Degussa P25 TiO_2 particles, have been monitored by time-resolved microwave conductivity and found to undergo equilibrium localization and eventual recombination at the particle surface. In the presence of isopropyl alcohol recombination is retarded due to surface hole scavenging. The particle bulk can then be pumped with mobile electrons, which survive for seconds.
A new method is described for the analysis of high precision pulse annealing data obtained using IRSL measurements on potassium feldspars using a Risoe reader. Presenting the data as the percentage of the signal lost per annealing phase permits more detailed comparisons to be made between samples. In addition, it is possible to directly compare the temperatures at which the TL and IRSL signals are released, thus giving information about the relationship between them. This method of analysis is applied to pulse annealing data for natural, irradiated, preheated and IR bleached aliquots. (author).
Basal cell carcinoma (BCC) is the most frequent cutaneous neoplasm, with a generally favorable clinical behavior. Sometimes, indeed, it recurs after therapy and/or metastasizes. As point mutations in the coding sequence of the p53 tumor suppressor gene have been implicated in the progression of many human tumors, we studied the expression of p53 protein on this neoplasia. We tested immunohistochemically the positivity for p53 protein (NCL-p53-CM1, YLEM) on 19 cases of morphologically "non aggressive" BCC (BCC1) and on 19 "aggressive" BCC (BCC2), all with one or more relapses and 3 with distant metastases also. Results were related to clinico-pathological and follow-up data. All but one BCC2 were found positive for p53 protein. Conversely, only 2 cases of BCC1 exhibited low immunoreactivity for p53 protein, with high statistical differences between the two groups. No correlation was found between the ...
Proteomic changes in proteins secreted by human hepatocellular carcinomas (HepG2) cells exposed to butyl benzyl phthalate (BBP) were evaluated. HepG2 cells were treated with three different concentrations of BBP (0, 10, or 25 ?M) for 24 or 48 h. Following incubation, the cells were subjected to proteomic analysis using two different pI ranges (4-7 and 6-9) and large-size two-dimensional gel electrophoresis. Results showed resolution of a total of 2776 protein spots. Of these, 29, including 19 upregulated and 10 downregulated proteins, were identified by electrospray ionization-mass spectrometry-mass spectrometry (ESI-MS/MS). Among these, the identities of cystatin C, Rho guanine nucleotide dissociation inhibitor, gelsolin, DEK protein, Raf kinase inhibitory protein, triose phosphate ...
Macronutrient self-selection and responses to dietary protein dilution were investigated in Senegalese sole, a flatfish species of interest for Mediterranean aquaculture. Eight groups of six sole were distributed among 75-l tanks and allowed to feed on three experimental diets composed of pure macronutrients: PC (75% crude protein and 25% carbohydrate), PF (75% crude protein and 25% crude fat) and PFC (10% crude protein, 45% crude fat and 45% carbohydrate). Choosing from the above diets, the sole selected a diet containing 68.0% crude protein, 15.7% crude fat and 16.3% carbohydrate. When the PF diet was diluted 50% with cellulose, the fish increased their feed intake to sustain the energy intake (5.0?kJ/kg BW/day). Their selection of fat remained unchanged, while carbohydrate selection sig...
Expressed sequence tags (ESTs) of the maxillary galea of the silkworm were analyzed to identify proteins involved in food selection systems. From the 1251 redundant genes of the ESTs, we identified 7 odorant-binding protein-like genes (bmObpL), 6 takeout-like genes (bmToL), and 6 chemosensory protein genes (bmCsp). Quantitative RT-PCR analysis indicated that bmObpL1, bmObpL2, bmObpL3, bmObpL5, bmToL1, bmToL3, and bmorCsp15 were predominantly expressed in the larval oral appendages, such as the maxilla, labrum, labium and antenna. Immunocytochemical analysis indicated that the proteins of bmObpL1, bmObpL3, and bmToL1 were localized in the gustatory chemosensilla on the maxillary galea and olfactory sensilla in the antenna. The proteins encoded by bmObpL1 and bmObpL3 were detected in the gus...
Human complement protein C9 is shown to be a metalloprotein that binds 1 mol of Ca"2"+/mol of C9 with a dissociation constant of 3 #mu#m as measured by equilibrium dialysis. Incubation with EDTA removes the bound calcium, resulting in a apoprotein with decreased thermal stability. This loss in stability leads to aggregation and, therefore, to loss of hemolytic activity upon heating to a few degrees above the physiological temperature. Heat-induced aggregation of apoC9 can be prevented by salts that stabilize proteins according to the Hofmeister series of lyotropic ions, suggesting that the ion in native C9 may ligand with more than one structural element of domain of the protein. Ligand blotting indicates that the calcium binding site is located in the amino-terminal half of the protein. Removal of calcium by inclusion of EDTA in assay mixtures has no effect on the hemolytic activity of C9, and its ...
The subjects covered in this Symposium range through almost every clinical medical specialty. From an average of one paper in each of the past three Symposiums, the explosive interest in cerebral amyloidosis has led to the presentation of 12 papers on this subject in the present volume. The genetically predisposed familial amyloidotic processes, such as the polyneuropathies and familial Mediterranean fever have also stimulated extensive and intriguing investigations which have revealed the striking effect of a single amino acid substitution in transforming a normal protein into a lethal ''amyloidogenic'' one. This Symposium clearly depicts the advances since the first amyloid fibril protein was definitively identified and defined 14 years ago. Since all amyloid fibril proteins so far described are variants of normal proteins, attention to gene abnormalities now becomes a significant focus as well as the ...
The authors have previously identified a small-cell lung cancer cell line (NCI-H209) that expresses an aberrant, underphosphorylated form of the retinoblastoma protein RB1. Molecular analysis of RB1 mRNA from this cell line revealed a single point mutation within exon 21 that resulted in a nonconservative amino acid substitution (cysteine to phenylalanine) at codon 706. Stable expression of this mutant RB1 cDNA in a human cell line lacking endogenous RB1 demonstrated that this amino acid change was sufficient to inhibit phosphorylation. In addition, this cysteine-to-phenylalanine substitution also resulted in loss of RB1 binding to the simian virus 40 large tumor and adenovirus E1A transforming proteins. These results confirm the importance of exon 21 coding sequences and suggest that the cysteine residue at codon 706 may play a role in achieving a specific protein conformation essential for ...
The MTX explored the plasma heating effects of 140 GHz microwaves from both Gyrotrons and from the IMP FEL wiggler. The Gyrotron was long pulse length (0.5 seconds maximum) and the FEL produced short-pulse length, high-peak power, single and burst modes of 140 GHZ microwaves. Full-power operations of the IMP FEL wiggler were commenced in April of 1992 and continued into October of 1992. The Experimental Test Accelerator H (ETA-II) provided a 50-nanosecond, 6-MeV, 2--3 kAmp electron beam that was introduced co-linear into the IMP FEL with a 140 GHz Gyrotron master oscillator (MO). The FEL was able to amplify the MO signal from approximately 7 kW to peaks consistently in the range of 1--2 GW. This microwave pulse was transmitted into the MTX and allowed the exploration of the linear and non-linear effects of short pulse, intense power in the MTX plasma. Single pulses were used to ...
Biosorption of uranium by residual biomass from The Old Bushmill`s Distillery Co. Ltd., Bushmills, Co. Antrim, Northern Ireland, following exposure to short and intense electric pulses has been examined. The biomass was prepared from the distillery spent wash and consisted of non-viable yeast and bacterial cells. As shown previously, untreated biomass had a maximum biosorption capacity of 170 mg uranium/g dry weight biomass. When biosorption reactions were placed between two electrodes and exposed to electric pulses with field strengths ranging from 1.25-3.25 kV/cm at a capacitance of 25 {mu}F, biosorption increased from 170 mg of uranium to 275 mg uranium/g dry weight biomass. The data were obtained from biosorption isotherm analyses and taken as the degree of biosorption at residual uranium concentrations of 3 mM. In addition, when the capacitance of the electric pulses increased from 0.25 {mu}F to 25 {mu}F at a fixed ...
Activation dose rates have been computed for the Poloidal Divertor Experiment Tokamak at the Princeton Plasma Physics Laboratory. Dose rates were computed in one-dimensional (cylindrical) geometry using the ANISN S/sub n/ transport theory code and the DKR radioactivity code. The EPR (DLC37F) 121-group coupled neutron-gamma cross section library was used with ANISN. For DKR, the 46-group neutron library of DCDLIB was employed. Dose rates were calculated for 1 minute, 1 hour, 6 hours, 24 hours, 1 week, and 1 month following a single pulse yielding 10/sup 15/ neutrons and for 2 hypothetical pulsing sequences. First, it was assumed that 10 pulses were conducted each day (1 hour apart) for 5 days. Second, it was assumed that 100 pulses were conducted each day (6 minutes apart) for 5 days. It was found that /sup 56/Mn and /sup 64/Cu are the main contributors to the dose at short time periods after shutdown, ...
The first long pulse production of high power D"- ion beams has been demonstrated in the JT-60 U negative ion sources, each of which was designed to produce 22 A, 500 keV D"- ion beams. Voltage holding capability and the grid power loading were examined for long pulse production of high power D"- ion beams. From the correlation between voltage holding and the light intensity of cathodoluminescence from the Fiber Reinforced Plastic insulators, the acceleration voltage for stable voltage holding capability was found to be less than 320-340 kV where the light was sufficiently suppressed. By tuning the extraction voltage, the grid power loadings in the ion sources were decreased to the allowable levels for long pulse injection without a significant reduction of the beam power. After tuning the acceleration and extraction voltages, D"- ion beams of 12.5 and 9.8 A were produced at 340 keV with cesium seeding at a rate of ...
Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for ...
The paper discusses recent results on the development of localized arc filament plasma actuators and their use in controlling high-speed and high Reynolds number jet flows. Multiple plasma actuators (up to 8) are controlled using a custom-built 8-channel high-voltage pulsed plasma generator. The plasma generator independently controls pulse repetition rate (0-200 kHz), duty cycle and phase for each individual actuator. Current and voltage measurements demonstrated the power consumption of each actuator to be quite low (20 W at 20% duty cycle). Emission spectroscopy temperature measurements in the pulsed arc filament showed rapid temperature increase over the first 10-20 ?s of arc operation, from below 1000 deg. C to up to about 2000 deg. C. At longer discharge pulse durations, 20-100 ?s, the plasma temperature levels off at approximately 2000 deg. C. Modelling calculations using an unsteady, ...
Electronic circular dichroism (ECD) of the n-#pi# and #pi# -#pi# transitions of the amide groups in the ultraviolet has become an indispensable tool for qualitative characterization of proteins in solution. Since the existence of such a spectrum (that is, of natural optical activity) comes from the three dimensional interaction of the chromophores in the molecule, CD is exquisitely sensitive to molecular conformation. However, in proteins, the amide transitions available in the near UV are limited in number and are broads and overlapping. Interactions among them yield information about the polymeric backbone, but since such amide electronic excitation are relatively delocalized, the resulting
Exposure of the freshwater field crab Barytelphusa guerini to a sublethal concentration of NaF (30 mg litre(-1)) caused significant alterations in protein metabolism. After an exposure time of 15 days, the crab was found to have a marked depletion of total protein and free amino acid content. A significant elevation in transaminases, Aspartate aminotransferase (AAT) and Alanine aminotransferase (ALAT), and Glutamate dehydrogenase (GDH) activities was reflected in the free amino acid levels of the tissues. PMID:15092215
The term "homology" or "homologous" means an amino acid similarity measured by the program, BLAST (Altschul et al (1997), "Gapped BLAST and PSI-BLAST: a new generation of protein database search programs", Nucleic Acids Res. 25:33 89 3402), and expressed as --(% identity n/n). In measuring homology between a peptide and a protein of greater size, homology is measured only in the corresponding region; that is, the protein is regarded as only having the same general length as the peptide, allowing for gaps and insertions.
Amyloid precursor protein (APP), a key protein in pathogenesis of Alzheimer's disease (AD), is a type I transmembrane protein which can be cleaved by b- and g-secretase to release the amyloidogenic b-amyloid peptides (Ab) and the APP intracellular domain (AICD). While Ab has been widely believed to initiate pathogenic cascades culminating AD, the physiological functions and regulations of AICD remain elusive. In present study, endogenous AICD was demonstrated to be increased by canonical Wnt signal. Instead of due to g-secretase activity, enhanced AICD expression was found due to the increased protein stability by Wnt/b-catenin. b-Catenin was demonstrated to be an associating partner of AICD, capable of promoting AICD mediated transcriptional activity. Investigation by AICD mutants proved ...
In previous studies we have demonstrated that prion protein (PrP) interacts with tubulin and disrupts microtubular cytoskeleton by inducing tubulin oligomerization. These observations may explain the molecular mechanism of toxicity of cytoplasmic PrP in transmissible spongiform encephalopathies (TSEs). Here, we check whether microtubule associated proteins (MAPs) that regulate microtubule stability, influence the PrP-induced oligomerization of tubulin. We show that tubulin preparations depleted of MAPs are more prone to oligomerization by PrP than those containing traces of MAPs. Tau protein, a major neuronal member of the MAPs family, reduces the effect of PrP. Importantly, phosphorylation of Tau abolishes its ability to affect the PrP-induced oligomerization of tubulin. We propose that t...
Within the cardiac cell, the movements of calcium ions are tightly regulated by a number of regulatory proteins including pumps, and channels. The sarcoplasmic reticulum (SR) is in large part...Full Text Available
We describe the stabilization by pressure of enzymes, including a hydrogenase from Methanococcus jannaschii, an extremely thermophilic deep-sea methanogen. This is the first published...Full Text Available
Eukaryotic genomes are packaged in two basic forms, euchromatin and heterochromatin. We have examined the composition and organization of Drosophila melanogaster heterochromatin in...Full Text Available
BackgroundPlasmodium falciparum is the most malignant agent of human malaria. It belongs to the taxon Laverania, which includes other ape-infecting Plasmodium...Full Text Available
The identification of individuals at risk for Alzheimer's disease (AD) is essential for the timely administration of treatment approaches aimed at slowing the onset or progression of the disease....Full Text Available
... growth hormone-like factor from plerocercoids of the tapeworm Spirometra mansonoides is a multifunctional protein. In Parasites and pathogens: ... ...
BackgroundGenetic predisposition to scrapie in sheep is associated with several variations in the peptide sequence of the prion protein gene (PRNP). DNA-based tests...Full Text Available
Orphan G protein-coupled receptors (GPCRs) are receptors lacking endogenous ligands. Found by molecular biological analyses, they became the roots of reverse pharmacology, in which receptors are attempted...Full Text Available
The Liver Carcinogenesis Section uses the modern technologies of molecular biology, cell biology, protein chemistry and genetics to investigate the biochemical and genetic pathways involved in human liver cancer.
Human heat shock protein 27 (Hsp27, HspB1) is an anti-apoptotic protein characterized for its tumorigenic and metastatic properties, and now referenced as a major therapeutic target in many types of cancer. Hsp27 biochemical properties rely on a structural oligomeric and dynamic organization. Downregulation by small interfering RNA or inhibition with dominant-negative mutant have proven their efficiency to counteract the anti-apoptotic and protective properties of Hsp27. In this study, we report the isolation and characterization of Hsp27-targeted molecules interfering with its structural organization. Using the peptide aptamer (PA) strategy, we isolated PAs that specifically interact with Hsp27 and not with the other members of the small heat shock protein family. In mammalian cell cultur...
The tetrapeptide KDEL is commonly found at the C terminus of soluble proteins of the endoplasmic reticulum (ER), and it contributes to their localization by interacting with a receptor that recycles...Full Text Available
Contractile vacuole complexes are critical components of cell volume regulation and have been shown to have other functional roles in several free-living protists....Full Text Available
Hydrophobic labelling is frequently used in the study of membrane-inserted domains of intrinsic proteins. However, the published procedures, fail to incorporate sufficient radioactivity into membrane immunoglobulins of B lymhocytes to permit investigation of their subunit structures and associations with other proteins. In order to increase the specific radioactivity of ["1"2"5I]iodonaphtylazide ["1"2"5I]INA), an improved method for the synthesis of the reagent was developed. In addition, the optimal conditions for labelling B lymhpocytes with ["1"2"5I]INA and commercially available reagent 3-(trifluoromethyl)-3-(trifluoromethyl)-3-(3'-["1"2"5Iliodophenyl)diazirine (["1"2"5I]TID were isolated and analysed in detail by SDS-PAGE. The usefulness of the two reagents for the investigation of lipid-embedded domains of membrane proteins is discussed. (author). 28 refs.; 4 figs.
The PbII binding characteristics of the previously reported PbII binding proteins of rat kidney cytosol were investigated further. Saturation and Scatchard analysis of /sup 203/Pb binding in whole cytosol and in 40% saturated ammonium sulfate precipitated fractions disclosed a class of relatively high-affinity sites with an apparent Kd of approximately 50 nM and binding capacities of approximately 41 and 9 pmol/mg of protein, respectively. Two /sup 203/Pb binding proteins with approximate molecular masses of 63K and 11.5K daltons and a high molecular weight component (greater than 200K) were isolated by Sepharose-6B column chromatography. The time course of association of /sup 203/Pb with cytosol and the 63K protein showed maximum binding at 18 hr which was stable up to 25 hr at 4 degrees C. The approximate half-time dissociation rate (T 1/2) of specifically bound /sup 203/Pb to the 63K ...
The PbII binding characteristics of the previously reported PbII binding proteins of rat kidney cytosol were investigated further. Saturation and Scatchard analysis of "2"0"3Pb binding in whole cytosol and in 40% saturated ammonium sulfate precipitated fractions disclosed a class of relatively high-affinity sites with an apparent Kd of approximately 50 nM and binding capacities of approximately 41 and 9 pmol/mg of protein, respectively. Two "2"0"3Pb binding proteins with approximate molecular masses of 63K and 11.5K daltons and a high molecular weight component (greater than 200K) were isolated by Sepharose-6B column chromatography. The time course of association of "2"0"3Pb with cytosol and the 63K protein showed maximum binding at 18 hr which was stable up to 25 hr at 4 degrees C. The approximate half-time dissociation rate (T 1/2) of specifically bound "2"0"3Pb to the 63K protein ...
BackgroundAlterations in protein composition and oxidative damage of high-density lipoprotein (HDL) have been proposed to impair the cardioprotective properties of...Full Text Available
Fava beans (Vicia fava) are cultivated rather widely in most countries of the Eastern Mediterranean area and provide a cheap but protein-rich food that can be eaten alone, in various...Full Text Available
BackgroundEnzyme-linked immunosorbent assay (ELISA) is a standard immunoassay to estimate a protein's concentration in a sample. Deploying ELISA in a microarray format permits simultaneous...Full Text Available
Aims A depressed cGMP-dependent protein kinase (PKG) activity is implicated in nitrate tolerance. The present study determines whether the leucine zipper-positive (LZ+) isoform of myosin phosphatase target subunit 1 (MYPT1), a key target protein for PKG actions, is involved in the development of nitrate tolerance. Methods and results Nitrate tolerance in in vitro preparations was obtained by a 24 h incubation with nitroglycerin (NTG). Nitrate tolerance in in vivo preparations was obtained by subcutaneous injection of mice with NTG, and the aortas were used. Protein levels of total MYPT1, MYPT1 (LZ+), PP1Cd, myosin light chain (MLC), and phosphorylated MLC were determined by Western blot analysis. Isometric vessel tension was determined by an organ chamber technique. Protein levels of MYPT1...
Functional properties of commercial and membrane processed pea protein isolates (PPI) prepared from yellow peas were investigated. Four protein isolates were prepared from yellow pea flour using water and KCl extractions at 25^oC followed by ultrafiltration and diafiltration (UF and DF) at pHs of 7.5 and 7.5 or 6 respectively. Following assessment of compositional attributes; solubility, foaming, flow and dynamic rheology, emulsification ability and heat-induced textural and rheological properties of prepared PPIs and a commercially available PPI were tested and compared. Membrane purification of proteins resulted in 28% to 68% reduction in phytic acid and enhanced, comparatively, the tested functional properties. Solubility of membrane processed PPIs, at all tested pHs, was superior and t...
Results in this study are consistent with those of Murdock and his colleagues who clearly demonstrated that clonidine, an agonist of octopaminergic receptors in some insects, significantly increases sucrose feeding. Their studies, however, did not examine the effect of clonidine on protein feeding. Injection of a 20mg/ml/fly dose of clonidine significantly reduces protein feeding in both sexes of Phormia regina, instead of stimulating feeding as is observed with carbohydrate feeding. The manner in which the flies are fed prior to starvation and the method of testing influences the amounts of diet consumed. It is proposed that the biogenic amines influence the state of hunger (i.e., protein versus carbohydrates) while other chemicals and neural mechanisms (i.e., such as sulfakinins and stre...
The cAMP response element-binding protein (CREB) is a highly conserved transcription factor that integrates signaling through the cAMP-dependent protein kinase A (PKA) in many eukaryotes. PKA plays a critical role in Dictyostelium development but no CREB homologue has been identified in this system. Here we show that Dictyostelium utilizes a CREB-like protein, BzpF, to integrate PKA signaling during late development. bzpF^- mutants produce compromised spores, which are extremely unstable and germination defective. Previously, we have found that BzpF binds the canonical CRE motif in vitro. In this paper, we determined the DNA binding specificity of BzpF using protein binding microarray (PBM) and showed that the motif with the highest specificity is a CRE-like sequence. BzpF is necessary to ...
When casein, a milk protein, is hydrolyzed, it renders human foods that contain it (e.g., hypoallergenic infant formula, cheeses) distasteful to many people. This rejection...Full Text Available
The synapsin III gene, SYN3, which belongs to the family of synaptic vesicle-associated proteins, has been implicated in the modulation of neurotransmitter...Full Text Available
Individual photophysical parameters of the chromophore of a fluorescent protein mRFP1 and its two mutants (amino-acid substitution at position 66 - mRFP1/ Q66C and mRFP1/Q66S proteins) are determined. For this purpose, apart from conventional methods of fluorimetry and spectrophotometry, nonlinear laser fluorimetry is used. It is shown that the individual extinction coefficients of the chromophore of proteins correlate (correlation coefficient above 0.9) with the volume of the substituted amino-acid residue at position 66 (similar to the positions of the absorption, fluorescence excitation and emission maxima). (laser biology and medicine)
Chemically reactive compounds in tissues can be monitored through their products of reaction with biomacromolecules. For the purpose of in vivo dose monitoring, hemoglobin (Hb) has been preferred to...Full Text Available
What genes are related to AEC syndrome? AEC syndrome is caused by mutations in the TP63 gene. This gene provides instructions for making a protein known as p63, which plays an...
BackgroundAmino-terminal signal peptides (SPs) are short regions that guide the targeting of secretory proteins to the correct subcellular compartments in the cell. They are cleaved...Full Text Available
Gaseous Nitrogen Dewar apparatus developed by Dr. Alex McPherson of the University of California, Irvine for use aboard Mir and the International Space ...