cssi/SciSciGPT-SciSciNet huggingface dataset:
Absolute Quantification of Specific Proteins in Complex Mixtures Using Visible Isotope-Coded Affinity Tags

The identification of proteins in complex mixtures is most useful when quantitative information is also obtained. We describe a new type of protein tagging reagent called the visible isotope-coded affinity tag (VICAT) which allows the absolute amount of a target protein or proteins to be quantified in a complex biological sample such as a eukaryotic cell lysate. VICAT reagents tag thiol groups of cysteines or thioacetylated amino groups and introduce into the tryptic peptide a biotin affinity handle, a visible moiety for tracking the chromatographic location of the target peptide by a method other than mass spectrometry, a photocleavable linker for removing a portion of the tag, and an isotope tag for distinguishing sample and internal standard peptides. We demonstrate the use of VICAT reagents together with isoelectric focusing of peptides on an immobilized gel strip followed by combined micro-liquid chromatography/electrospray ionization mass spectrometry operating in selected reaction monitoring mode t...
Visualizing vector fields using line integral convolution and dye advection

We present local and global techniques to visualize three-dimensional vector field data. Using the Line Integral Convolution (LIC) method to image the global vector field, our new algorithm allows the user to introduce colored "dye" into the vector field to highlight local flow features. A fast algorithm is proposed that quickly recomputes the dyed LIC images. In addition, we introduce volume rendering methods that can map the LIC texture on any contour surface and/or translucent region defined by additional scalar quantities, and can follow the advection of colored dye throughout the volume.
Participation of Escherichia coli DNA in the replication of temperate bacteriophage Mu1.

Abstract Four discrete species of DNA that appear after the infection of a sensitive strain of Escherichia coli K12 with temperate phage Mu1 have been identified by neutral and alkaline sucrose gradient centrifugation, CsCl-ethidium bromide equilibrium gradient centrifugation, electron microscopy, differential labeling and DNA-DNA hybridization. Form I (32S) resembles the DNA extracted from phage particles. Form II is also linear but sediments faster (39 S). Form II (46 S) is a relaxed ring form with and without “tails.” Form IV (55 S and faster) consists of covalently closed superhelical rings. Forms III and IV exhibit a continuous range of weights between 25 and 134 × 106 daltons. All forms contain host DNA. Excision of DNA of the length of phage DNA from an intermediate made of alternating segments of host and phage DNA is proposed to account for the generation of phage DNA molecules containing host DNA at their “variable end,” and for the formation of the generalized transducing DNA found in Mu particles.
Small Interference RNA-mediated Gene Silencing of Human Biliverdin Reductase, but Not That of Heme Oxygenase-1, Attenuates Arsenite-mediated Induction of the Oxygenase and Increases Apoptosis in 293A Kidney Cells

BVR reduces biliverdin, the HO-1 and HO-2 product, to bilirubin. Human biliverdin (BVR) is a serine/threonine kinase activated by free radicals. It is a leucine zipper (bZip) DNA-binding protein and a regulatory factor for 8/7-bp AP-1-regulated genes, including HO-1 and ATF-2/CREB. Presently, small interference (si) RNA constructs were used to investigate the role of human BVR in sodium arsenite (As)-mediated induction of HO-1 and in cytoprotection against apoptosis. Activation of BVR involved increased serine/threonine phosphorylation but not its protein or transcript levels. The peak activity at 1 h (4-5-fold) after treatment of 293A cells with 5 mum As preceded induction of HO-1 expression by 3 h. The following suggests BVR involvement in regulating oxidative stress response of HO-1: siBVR attenuated As-mediated increase in HO-1 expression; siBVR, but not siHO-1, inhibited As-dependent increased c-jun promoter activity; treatment of cells with As increased AP-1 binding of nuclear proteins; BVR was identified in the DNA-protein complex; and AP-1 binding of the in vitro translated BVR was phosphorylation-dependent and was attenuated by biliverdin. Most unexpectedly, cells transfected with siBVR, but not siHO-1, displayed a 4-fold increase in apoptotic cells when treated with 10 mum As as detected by flow cytometry. The presence of BVR small interference RNA augmented the effect of As on levels of cytochrome c, TRAIL, and DR-5 mRNA and cleavage of poly(ADP-ribose) polymerase. The findings describe the function of BVR in HO-1 oxidative response and, demonstrate, for the first time, not only that BVR advances the role of HO-1 in cytoprotection but also affords cytoprotection independent of heme degradation.
Symposium: Optics Along The Rio Grande Research Corridor

New Mexico's scientific, technological, and educational resources are concentrated along a 300-mile stretch of the Rio Grande, from Los Alamos in the north to Las Cruces in the south. This area contains two major multidisciplinary national laboratories (Los Alamos and Sandia), three military R&D centers, three state universities, and numerous other technology based organizations, including a growing number of "high-tech" businesses and industries.
Crystal-field effects in fluoride crystals for optical refrigeration

The total crystal-field splitting of the 2F7/2 ground-state multiplet of Yb3+ critically determines the cooling efficiency of an optical refrigerator. Crystals with a small 2F7/2 splitting maintain a sizeable thermal population of the initial state of the pumped crystal-field transition at low temperatures, leading to a workable laser-cooling efficiency in the application-relevant cryogenic regime below 120 K. A comprehensive review of the crystal-field splitting of (2S+1)L(J) multiplets in rare-earth-doped fluoride crystals is presented. The concept of crystal-field strength is used to predict the splitting of the 2F7/2 ground-state multiplet from other fluoride crystals doped with other rare earth ions. The analysis correctly predicts the typical 350-450 cm-1 total splitting of 2F7/2 in fluorides, but the accuracy of the method is found to be rather limited. LiKYF5, K2YF5, and Cs2KLnF6 are predicted to have large 2F7/2 splittings that are unfavorable for laser cooling. KY3F10, YLiF4, LuLiF4, and GdLiF4 are among the group of crystals expected to have small 2F7/2 splittings and currently appear to be the most promising hosts for laser cooling with Yb3+. LiBiF4:Yb3+ may have a <350 cm-1 2F7/2 splitting and warrants further study.
Quantification of plasma HIV RNA using chemically engineered peptide nucleic acids

The remarkable stability of peptide nucleic acids (PNAs) towards enzymatic degradation makes this class of molecules ideal to develop as part of a diagnostic device. Here we report the development of chemically engineered PNAs for the quantitative detection of HIV RNA at clinically relevant levels that are competitive with current PCR-based assays. Using a sandwich hybridization approach, chemical groups were systematically introduced into a surface PNA probe and a reporter PNA probe to achieve quantitative detection for HIV RNA as low as 20 copies per millilitre of plasma. For the surface PNA probe, four cyclopentane groups were incorporated to promote stronger binding to the target HIV RNA compared with PNA without the cyclopentanes. For the reporter PNA probe, 25 biotin groups were attached to promote strong signal amplification after binding to the target HIV RNA. These general approaches to engineer PNA probes may be used to detect other RNA target sequences.
Precise area-controlled return-to-zero current steering DAC with reduced sensitivity to clock jitter

A precise return-to-zero current steering DAC is presented. This architecture uses a scaled switched-capacitor replica and a comparator to integrate the current over time, resulting in an accurate pulse. Without significant increase in the pulse height, the generated pulse can have its minimal value at the end of the DAC phase, hence minimizing the clock jitter effect. The proposed DAC can be used in continuous-time delta-sigma modulators to achieve high accuracy even in presence of the clock jitter. Simulation results are provided to prove the efficiency of this structure.
Microtubule Binding and Rotation of the Kinesin-14 Stalk

Movement of motors along cytoskeletal filaments is thought to be driven by small structural changes that are amplified by a large rotation of the alpha-helical coiled coil. The coiled-coil stalk of the kinesin-14 motor, Ncd, has been visualized in a rotated conformation in a crystal structure and proposed to act like a lever to amplify force produced by the motor, resulting in a working stroke that directs the motor to the microtubule minus end. We show here that an Ncd mutant that is trapped in a stalk-rotated conformation binds tightly to microtubules and shows fluorescence resonance energy transfer between the end of the stalk and microtubule, indicating that rotation of the stalk towards the microtubule is coupled to motor binding to microtubules. A mutant blocked in stalk rotation binds weakly to microtubules and shows no energy transfer, demonstrating that binding by the motor to microtubules requires movement of the stalk. Energy transfer assays show that wild-type Ncd binds to microtubules without added nucleotide with the end of the stalk more than ∼9 nm from the microtubule, rotating less than 50 degrees from a position perpendicular to the microtubule. Upon binding with a non-hydrolysable ATP analogue, the stalk lies within ∼6 nm of the microtubule surface, representing a rotation of ∼70 degrees. These findings are consistent with previous reports by cryoEM that the Ncd stalk rotates when the microtubule-bound motor binds ATP. However, our results indicate that stalk rotation is initiated by filament binding and ADP release, and completed upon ATP binding, rather than triggered by ATP binding. Initiation of the Ncd stalk rotation by microtubule binding and ADP release, and its completion on ATP binding is reminiscent of the two-step working stroke of myosin I, revealing an unexpected similarity between the motors.
A note on the quantum fluctuations of O(n) symmetric theory

Fluctuations of scalar field inO(n) symmetric theory are studied. The dependence of fluctuations uponn is given. Our result shows that the field withn = 2 is highly fluctuated. In this case the approximation based on the expansion about the classical theory is not applicable.
A novel method of producing lightweight microcellular injection molded parts with improved ductility and toughness

Abstract This paper presents a novel method and the underlying mechanisms of improving the ductility and toughness of polymer blend components using microcellular injection molding. By producing a special microcellular structure and morphology in polymer blends of proper material formulations, the ductility and toughness of the foamed parts can be significantly improved compared to those of solid parts. The key is to achieve a microcellular structure with a sub-micron scale immiscible secondary phase uniformly dispersed in the primary polymer matrix. Upon tensile loading, cavitation of the secondary phase facilitates the interconnection of microcellular voids to form channels such that the stretched component transforms into a bundle of fibrils. This change in structure turns the fracture mechanism from crack propagation across the matrix into shear yielding of a bundle of fibrils in the loading direction. Process conditions, microstructures, phase morphologies, and mechanical test results of three different types of polymer blends, namely, polypropylene/high-density polyethylene (PP/HDPE), polypropylene/low-density polyethylene (PP/LDPE), and poly(lactic acid)/poly(3-hydroxybutyrate-co-3-hydroxy-valerate) (PLA/PHBV) blends, are presented. Compared with other toughening methods, this method achieved a more significant improvement in ductility and toughness while reducing material consumption and part weight.
Proteolysis alters the spectral properties of 124 kdalton phytochrome from Avena.

Native phytochrome from Avena sativa L. is homogeneous with a monomeric molecular weight of 124 kdalton; 6–10 kdalton larger than the heterogeneous “120” kdalton preparations previously considered to be undegraded (Vierstra and Quail, 1982, Proc. Natl. Acad. Sci. USA, 79: 5272–5276). The phototransformation difference spectrum (Pr-Pfr) of 124 kdalton phytochrome measured in crude extracts has a minimum in the farred region at 730 nm, the same as that observed in vivo. These spectral properties contrast with those of “120” kdalton phytochrome purified by column immunoaffinity chromatography where the difference minimum is at 724 nm. When 124 kdalton phytochrome is incubated as Pr in crude extracts, the difference minimum shifts progressively to shorter wavelengths (from 730 to 722 nm) concomitant with the proteolytic degradation of the chromoprotein to the mixture of 118 and 114 kdalton species that comprise “120” kdalton phytochrome preparations. These two effects are inhibited in concert by the serine protease inhibitor, phenylmethylsulfonylfluoride, and or maintenance of the phytochrome in the Pfr form. These results provide further evidence that 124 kdalton phytochrome is the native molecule in Avena and indicate that the peptide segments removed by proteolysis of the Pr form are important to the pigment's spectral integrity. The present data thus resolve the previously unsettled question of why the Pfr form of “120” kdalton phytochrome isolated by various procedures from Avena has been found to absorb at shorter wavelengths than that observed in vivo. Previous spectral studies with “120” kdalton phytochrome preparations are open to reexamination.
Data integration in a bandwidth-rich world

Inexpensive storage and wide-area bandwidth (with prices for both declining at least as fast as Moore's Law) drive demand for middleware to integrate, correlate, compare, and mine local, remote, and distributed data.
Construction and validation of a physician career development inventory

Abstract The development and psychometric characteristics of the Medical Career Development Inventory (MCDI) are described. The MCDI represents the initial construction of a career maturity measure for a homogeneous population of adults who encounter a common set of vocational development tasks. The inventory is intended to measure both degree of vocational development and readiness to cope with the developmental tasks encountered in a physician's career. The MCDI includes 35 items that address coping behaviors germane to dealing with the vocational tasks constituting the career development continuum of physicians. Initial evaluation of the MCDI's psychometric properties with a sample of 160 student-physicians supported the content validity of the items, construct validity of the scales, and criterion validity of the inventory.
Proton NMR Relaxation in Six-Coordinate Low-Spin Iron(III) Tetraphenylporphyrinates: Temperature Dependence of Proton Relaxation Rates and Interpretation of NOESY Experiments

The temperature dependence of longitudinal and transverse relaxation times (T1 and T2) has been studied for the pyrrole protons of [(p-Cl)3(p-NEt2)TPPFe(III)(N-MeIm)2]Cl (1), [(p-Cl)(p-NEt2)3TPPFe(III)(N-MeIm)2]Cl (2), and [TMPFe(III)(2-MeImH)2]Cl (3), where TMP = tetramesitylporphyrin and TPP = tetraphenylporphyrin, in the temperature range 190−310 K. All three complexes are paramagnetic and have electron spin S = 1/2. Up to 273 K, all complexes exhibit four distinct pyrrole proton signals, with the asymmetry caused by unsymmetrical substitution in complexes 1 and 2 and by axial ligands fixed in a definite orientation in complex 3. Above 273 K the four-peak pattern in complex 3 collapses into a single peak due to fast synchronous rotation of axial ligands. At low temperatures, T1s and T2s in all complexes increase as temperature increases. At higher temperatures, T1s continue to increase and equalize in complex 3, but decrease in complexes 1 and 2. T2s in complexes 1 and 2 mimic the T1s at all temperatur...
Neutrino decays of hadrons and the conservation laws of quantum numbers

The main considerations and the quantitative data on the lifetimes of particles against neutrino decay are presented in support of an idea advanced previously by the present author concerning the leptonic origin of hadrons. According to this idea, neutrino decays of hadrons follow naturally from the decays of leptons entering into the hadronic structure. In the conclusion of the article it is shown that certain laws of conservation of quantum numbers observed in particle interactions as well as departures from the laws are specified by the initial premises of the muonic model of hadrons. The model necessitates a review of the accepted particle classification.
High-throughput design of microfluidics based on directed bacterial motility

Use of motile cells as sensors and actuators in microfabricated devices requires precise design of interfaces between living and non-living components, a process that has relied on slow revision of device architectures as prototypes are sequentially evaluated and re-designed. In this report, we describe a microdesign and fabrication approach capable of iteratively refining three-dimensional bacterial interfaces in periods as short as 10 minutes, and demonstrate its use to drive fluid transport by harnessing flagellar motion. In this approach, multiphoton excitation is used to promote protein photocrosslinking in a direct-write procedure mediated by static and dynamic masking, with the resultant microstructures serving to capture motile bacteria from the surrounding fluidic environment. Reproducible steering and patterning of flagellated E. colicells drive microfluidic currents capable of guiding micro-objects on predictable trajectories with velocities reaching 150 µm s−1 and achieving bulk flow through microchannels. We show that bacteria can be dynamically immobilized at specified positions, an approach that frees such devices from limitations imposed by the functional lifetime of cells. These results provide a foundation for the development of sophisticated microfluidic devices powered by cells.
Peter Effect in the Preparation of Reading Teachers

The Peter Effect (Applegate & Applegate, 2004) claimed that one cannot be expected to give what one does not possess. We applied this notion to reading teacher preparation and hypothesized that teacher educators who do not possess an understanding of basic language constructs would not prepare teacher candidates with an understanding of these constructs considered essential for early reading success. Results from a survey of basic language constructs revealed similar patterns in performance between teacher educators and their respective teacher candidates, which served as initial validation of the Peter Effect in reading teacher preparation.
A Simple Proof That the Curl Defined as Circulation Density Is a Vector-Valued Function, and an Alternative Approach to Proving Stoke’s Theorem

This article offers a simple but rigorous proof that the curl defined as a limit of circulation density is a vector-valued function with the standard Cartesian expression.
f-Wave Decay of the 8.9-MeV Level in 13 N

Proton spin-flip in $^{12}\mathrm{C}(p,{p}_{1})^{12}\mathrm{C}$ (${2}^{+}$, 4.44 MeV) has been measured in the region of the 8.9-MeV ${\mathrm{\textonehalf{}}}^{\ensuremath{-}}$ level in $^{13}\mathrm{N}$. The inelastic decay is predominately by ${f}_{\frac{5}{2}}$ waves. The reduced width in the ${f}_{\frac{5}{2}}$ channel is about equal to the single-particle limit.
Synthesis of Cadmium Selenide Quantum Dots from a Non-Coordinating Solvent: Growth Kinetics and Particle Size Distribution

Here we report on the synthesis of CdSe quantum dots from a noncoordinating solvent. We show that nucleation and growth is very fast and is completed within 100 s. The subsequent increase in average particle size is due to diffusion limited coarsening. Growth and coarsening can be quenched by injection of dodecanethiol. Finally, we compare the size distribution obtained from analysis of the absorption edge with the size distribution obtained from analysis of transmission electron microscope images.
Nitrogen fixation efficiency, natural15N abundance, and morphology of mesquite (Prosopis glandulosa) root nodules

The relative nitrogen fixation efficiencies (RE 1-[H2 evolved÷C2H2 reduced]·100) of four mesquite (Prosopis glandulosa var.torreyana) rhizobia (Strains WR 1001, WR 1002, L5, L9) and a cowpea rhizobia (Strain 176A32) on mesquite were evaluated in a glasshouse experiment. Plant yield, shoot N accumulation, and the natural15N abundance (δ15N) of nodule tissue were determined. Strain WR 1002 failed to nodulate mesquite and strain L5 produced ineffective nodules. Among the three effective strains (WR 1001, L9, 176A32) the cowpea strain (176A32) and strain L9 had significantly higher RE than strain WR 1001. Differences in RE, however, were not accompanied by significantly higher plant yield and shoot N accumulation. The difference in15N abundance between foliar tissue and nodules (nodules minus leaves) was 0.47 δ15N for the ineffective L5 nodules, while for the effective WR 1001, L9, and 176A32 nodules, respectively, this difference was 8.35, 7.81, and 8.35 δ15N. This indicates a similar relationship between N2-fixing effectiveness and natural15N enrichment of nodules that was previously observed in soybeans (Glycine max, L. Merr.). Strains WR 1001 and L9 produced elongate, indeterminate nodules typical for mesquite. The ineffective L5 nodules had few infected cells and an abundance of cortical amyloplasts. Mesquite nodules produced by the cowpea strain were spherical and were somewhat more similar in internal morphology to determinate nodules typical of cowpea than indeterminate nodules normally associated with mesquite.
Ventricular dysphonia: a profile of 40 cases.

Ventricular dysphonia is a poorly understood disorder involving ventricular fold participation during phonation. A population of ventricular dysphonia patients was evaluated using phonatory function studies such as laryngovideostroboscopy, advanced acoustic analysis, and electroglottography to identify shared epidemiologic characteristics and to discuss possible neuromuscular mechanisms and causes. Forty patients with ventricular dysphonia were studied and epidemiologic, acoustic, and histologic data were analyzed. In almost all cases, the authors found abnormalities affecting the glottis caused by a related medical condition. The abnormalities included true vocal cord (TVC) aperiodicity in 100% of the patients, TVC asymmetry in 65%, a laryngeal mass or foreign body (usually Teflon®) in 35%, TVC erythema or edema in 32.5%, and TVC bowing in 22.5%. Ventricular dysphonia seems to be primarily a compensatory mechanism for glottic dysfunction. Therapy is based on identifying and correcting the underlying abnormalities. Laryngovideostroboscopy is a particularly important tool in examining chronic dysphonia.
Spectral analysis of whisking output via optogenetic modulation of vibrissa cortex in rat

Whisking motor output in awake and freely moving rat is investigated with optogenetic excitation/inhibition of the vibrissae motor cortex (vMCx) layer V. The goal of the study is to establish the direct causal relationship between the cortical activity and the whisking output using optical stimulation, excitatory or inhibitory, with different frequencies. Progression and reduction of the whisking frequency was obtained; however, the whisking frequency did not necessarily followed the entrainment stimulus. Based on our observations, the excitation of the vMCx doubled and inhibition reduced the whisking frequency to half, compared to control, at all stimulus frequencies. This result is an empirical evidence that the cortex exerted control through a central pattern generator structure since complete inhibition was not obtained and the frequency of the response was different from that of the stimulus. We suggest that the use of the optogenetic approach, which enabled us to perform the bidirectional modulation and direct readout from vMCx, has brought valid evidence for the causal connection between cortical activity and whisking motor output.
Digitization of sedimentation equilibrium and velocity data for analysis by minicomputer.

Abstract A fast, efficient, and accurate method to obtain solute sedimentation coefficients and molecular weights from analytical ultracentrifugation data is described. Recorder tracings from the photoelectric scanner of a Beckman Model E analytical ultracentrifuge are analyzed with a computer program after being entered into a minicomputer via a digitizer board. The method is a simple, low-cost, and resource-efficient alternative to complex methods of modifying the ultracentrifuge for similar purposes. Even nonideal and polydisperse solute samples may be analyzed. To illustrate this method sedimentation equilibrium data for a mutant bacterial luciferase, AK-6, are analyzed. Two major species are detected, the dimeric enzyme with an apparent mass average molecular weight, M w,app , of 71,000 and dissociated subunits with an M w,app of 40,000. This method is used to calculate the sedimentation coefficients of native and proteolyzed samples of bacterial luciferase from three species of luminous marine bacteria (Holzman, T. F., and Baldwin, T. O. (1980) Proc. Nat. Acad. Sci. USA77, 6363–6367).
Conjugated macrocycles related to the porphyrins. Part 2. Further synthetic and spectroscopic studies on difuryl analogs of the oxophlorins

The synthesis of three difuryl analogs of the oxophlorins is described. In common with the tetrapyrrolic oxophlorins, these compounds favor the keto tautomers and little, if any, of the enol tautomers are present in neutral solutions. Unlike the tetrapyrrolic systems, the difuryl oxophlorins give well resolved nmr spectra. Attempts to extend these studies to the synthesis of dithienyl oxophlorin analogs were unsuccessful
Status of Pharmacists in the Government Service and Under Selective Service

For many years each of the three national associations, American Pharmaceutical Association, American Association of Colleges of Pharmacy and National Association of Boards of Pharmacy, had a standing or annually appointed a committee on the Establishment of a Pharmaceutical Corps in the United States Army. The committees were appointed for the purpose explained by the committee title.
AMPA receptor subunit expression in the endoplasmic reticulum in frontal cortex of elderly patients with schizophrenia.

Several lines of evidence indicate altered trafficking of α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptors in schizophrenia. Previous reports have shown potential changes in the trafficking of AMPA receptors based on subunit expression of endosomes, subcellular organelles located near post-synaptic sites. We hypothesized that alterations in AMPA receptor trafficking through the endoplasmic reticulum (ER) may also be altered in schizophrenia. Accordingly, we developed a technique to isolate and measure content of the ER from postmortem brain tissue. We used Western blot and electron microscopy to show that we isolated an ER enriched fraction. We found no changes in the expression of the AMPA receptor subunits, GluR1–4, in the ER from the dorsolateral prefrontal cortex in schizophrenia. These data suggest that AMPA receptor trafficking through the ER is largely intact in schizophrenia.
Electromigration reliability improvement of W-plug vias by titanium layering

The electromigration (Er) performance of layered Al-0.5%Cu and Al-1%Si-0.5%Cu metallization systems was investigated, including leads with refractory barrier and capping layers, and tungsten-filled via holes. While the W-plugs exhibited a lifetime shorter than the leads, a dramatic improvement in EM performance of the vias was achieved by incorporating a thin layer of titanium between the aluminum and its cap. Among the most likely explanations for this observation is that the aluminum is protected from physical damage during via etch by the continuous TiAl/sub 3/ layer which forms by reaction between the titanium and the aluminum. Current flow simulations show complex crowding effects at the bottom of the vias. The role of grain boundaries and the effects of dopants on early via failure modes are also discussed. >
Introduction: The Journal of Popular Film & Television Legacy of Western Scholarship

Deadwood (HBO) Season 3, 2006. Shown: Brent Sexton. Photo courtesy of Photofest. (color figure available online) For nearly two centuries, Americans have embraced the Western like no other artistic...
Intradiscal electrothermal therapy (IDET) for the treatment of discogenic pain

Despite advances in imaging and interventional techniques, discogenic back pain continues to be a diagnostic and management challenge. Practitioners have sought the use of minimally invasive intradiscal thermal therapies for the relief of discogenic low back pain. Different techniques delivering heat to the disc have been developed, collectively known as thermal intradiscal procedures. The main focus of this review is dedicated to the most studied procedure, intradiscal electrothermal therapy (IDET), in the management of discogenic low back pain. Although IDET may be beneficial in a selected population of patients, evidence in support of wider use of IDET does not exist. The debate goes on regarding the efficacy of the available techniques.
Pentatricopeptide Repeat Proteins Stimulate mRNA Adenylation/Uridylation to Activate Mitochondrial Translation in Trypanosomes

Summary The majority of trypanosomal mitochondrial pre-mRNAs undergo massive uridine insertion/deletion editing, which creates open reading frames. Although the pre-editing addition of short 3′ A tails is known to stabilize transcripts during and after the editing, the processing event committing the fully edited mRNAs to translation remained unknown. Here, we show that a heterodimer of pentatricopeptide repeat-containing (PPR) proteins, termed k inetoplast p oly a denylation/uridylation f actors (KPAFs) 1 and 2, induces the postediting addition of A/U heteropolymers by KPAP1 poly(A) polymerase and RET1 terminal uridyltransferase. Edited transcripts bearing 200- to 300-nucleotide-long A/U tails, but not short A tails, were enriched in translating ribosomal complexes and affinity-purified ribosomal particles. KPAF1 repression led to a selective loss of A/U-tailed mRNAs and concomitant inhibition of protein synthesis. These results establish A/U extensions as the defining cis -elements of translation-competent mRNAs. Furthermore, we demonstrate that A/U-tailed mRNA preferentially interacts with the small ribosomal subunit, whereas edited substrates and complexes bind to the large subunit.
Voltage-dependent sodium currents recorded from dissociated rat taste cells

Voltage-dependent sodium currents were analyzed in detail from dissociated mammalian taste receptor cells using the whole-cell patch clamp technique. Approximately 50–75% of all taste receptor cells expressed sodium currents. These currents activated close to −50 mV (holding potential = −80 mV) with maximal currents most often occurring at −10 mV. The distribution of maximal inward currents across all cells appeared to display two peaks, at −254 pA and −477 pA, possibly due to differences in sodium channel density. Inward currents were eliminated by replacing 90% of external sodium with N-methyl-D-glucamine. The currentvoltage relationship of the activated current, as measured by a tail current analysis, was linear, suggesting an ohmic nature of the open channel conductance. The relationship between the time to the peak activated current and the step potential was well fit by a double exponential curve (τ1 = 6.18, τ2 = 37.8 msec). Development of inactivation of the sodium current was dependent upon both voltage- and temporal-parameters. The voltage dependence of the time constant (τ) obtained from removal of inactivation, development of inactivation, and decay of the sodium current displayed a bell-shaped curve with a maximum of 55 msec at −70 mV. In addition to fast inactivation (half maximal at −50 mV), these currents also displayed a slow inactivation (half maximal at −65 mV). Voltage-dependent sodium currents were reversibly inhibited by nanomolar concentrations of tetrodotoxin (Kd = 10−8 m). There was no evidence of a TTX-insensitive sodium current. This description broadens our understanding of gustatory transduction mechanisms with a particular relevance to the physiological role of receptor cell action potentials.
The economic impact of a shift from hard to fuzzy contracts

Purpose – This paper aims to explain the economic impact of the change in the degree of contract enforcement in the USA since August 2008. This change, from solid enforcement (hard contracts), to uncertain enforcement (fuzzy contracts), is a result of political expediency during an economic crisis. The purpose of the paper is to point out that political decisions are not made in an economic vacuum, and that there is an economic impact to the move away from hard contracts.Design/methodology/approach – The paper uses a time value of money, net present value approach with specific emphasis on the investor's adjustment to the required rate of return in the face of uncertain contract enforcement. Both closed and open economic systems are addressed.Findings – The paper finds that in the shift to a fuzzy contract environment, investors will increase the required rate of return on future investment contracts, thereby lowering the value of those assets. Both individually, and in the aggregate, asset values will fa...
Aharonov-Bohm oscillations, quantum decoherence and amplitude modulation in mesoscopic InGaAs/InAlAs rings

Low-temperature Aharonov–Bohm oscillations in the magnetoresistance of mesoscopic interferometric rings patterned on an InGaAs/InAlAs heterostructure are investigated for their dependence on excitation current and temperature. The rings have an average radius of 650 nm, and a lithographic arm width of 300 nm, yielding pronounced interference oscillations over a wide range of magnetic fields. Apart from a current and temperature dependence, the oscillation amplitude also shows a quasi-periodic modulation with applied magnetic field. The phase coherence length is extracted by analysis of the fundamental and higher Fourier components of the oscillations, and by direct analysis of the amplitude and its dependence on parameters. It is concluded that the Thouless energy forms the measure of excitation energies for quantum decoherence. The amplitude modulation finds an explanation in the effect of the magnetic flux threading the finite width of the interferometer arms.
Negative instances and mathematical concept acquisition

(1973). Negative instances and mathematical concept acquisition. Theory Into Practice: Vol. 12, Teaching the Young to Think, pp. 307-315.
Short-term interactions of aniline and benzidine with three soils in both natural and artificial matrices

The fate of aromatic amines in natural systems is important to understand due to the persistence and toxicity of these chemicals. Laboratory experiments were performed to elucidate aniline and benzidine behavior in silty-clay, sandy loam, and sandy soils, and six background matrices (rainwater, 12.5 mM CaCl(2), 25 mM CaCl(2), and each passed through soil columns). The goals of this study were to test the validity of using CaCl(2) as a laboratory simulation for rainwater and to observe how short-term sorption (24 h) of aniline and benzidine changed when these solutions were passed through soil columns. Results indicated that neither CaCl(2) solution exactly predicted the sorption of these chemicals in corresponding rainwater solutions, likely due to varying soil properties that influenced the sorption mechanisms. Statistical analyses revealed that the passage of rainwater or CaCl(2) solutions through soil columns did not significantly affect the sorption of aniline or benzidine. Cation exchange and solubility plots were created to identify the sorption mechanisms taking place in the short-term batch experiments. These plots indicated that cation exchange played a role in the sorption of both aniline and benzidine under all conditions, while solubility plots showed higher correlations for benzidine, a consequence of its lower aqueous solubility.
Thermal and mechanical properties of evacuated powders

Abstract This paper summarizes the effects of environmental and intrinsic powder parameters on the thermal and mechanical properties of evacuated powders. Thermal conductivity and diffusivity are controlled primarily by the residual gas pressure, temperature, particle size and shape, and mechanical load. Bearing strength is less dependent on temperature and gas pressure, but is strongly influenced by density, particle size and shape.
Producing the universal spectrum of cosmological gamma-ray bursts with the Klein-Nishina cross section

A power-law spectrum attenuated through Compton scattering by an optically thick medium produces spectra that have a characteristic energy of several hundred keV. Add a redshift, and one finds that this model can qualitatively reproduce the color-color diagrams found for individual gamma-ray bursts. This model is easily tested through model fits to burst spectra and through comparisons of the parameters derived from model fits to the limits on parameters derived from the burst log N - log P(sub max) curve. The heavy attenuation makes the amount of energy released in the burst approximately equal to 10(exp 3) times larger than is inferred from the observed flux. The requirements of high optical depth and no photon-photon pair creation place a lower limit on the size of the scattering region. This size suggests that the attenuation occurs in giant molecular clouds in the cores of galaxies. This indicates that gamma-ray bursts are probably from supermassive black holes. If the Lorentz factor of the radiation source is large, the optical depth, and therefore the hardness ratio of a burst, can change over the duration of the burst.
Modeling particle size distributions by the Weibull distribution function

Abstract A method is proposed for modeling two- and three-dimensional particle size distributions using the Weibull distribution function. Experimental results show that, for tungsten particles in liquid phase sintered W-14Ni-6Fe, the experimental cumulative section size distributions were well fit by the Weibull probability function, which can also be used to compute the corresponding relative frequency distributions. Modeling the two-dimensional section size distributions facilitates the use of the Saltykov or other methods for unfoldng three-dimensional (3-D) size distributions with minimal irregularities. Fitting the unfolded comulative 3-D particle size distribution with the Weibull function enables computation of the statistical distribution parameters from the parameters of the fit Weibull function.
Optimal radio frequency identification deployment in a supply chain network

Abstract In recent years, the use of radio frequency identification (RFID) within supply chain management has received considerable attention. A significant upfront investment together with uncertain return on investment, however, remain impediments to deployments of RFID systems. This paper proposes a novel approach to analyze the potential benefits of RFID systems. We suggest deployment strategies that determine an optimal location of RFID within a supply chain network. The resulting models can be used to evaluate the value of information with respect to item losses. In addition, we discuss methods for solving the resulting large-scale optimization problems, and analyze how various system characteristics impact optimal deployment strategies as well as the overall RFID benefits.
E-region temperature measurements at Millstone Hill

Abstract An incoherent scatter radar experiment involving the transmission of pairs of short pulses at various spacings was employed at Millstone Hill to study the daytime thermal structure of the lower thermosphere. An altitude range from 110 to 130 km was covered with a height resolution of 6 km. The daily temperature variation exhibited oscillations having dominant periods in the range 6–14 hr and amplitudes as large as 28 per cent of the mean temperature. These waves possessed a downward phase velocity indicating an energy source at lower heights. A spectral analysis carried out on measurements gathered on successive days provided sufficient frequency resolution to resolve the different tidal frequencies and indicated the 12-hr period as the main component. Interpreting the measured oscillations as being primarily a manifestation of the solar semidiurnal tide, the observed phase and vertical wavelength are in agreement with theoretical predictions for the thermal (2, 4) tidal mode propagating from the lower atmosphere. On average, the semidiurnal wave amplitude is about 40 K with a time of maximum near 0700 hr LT at 115 km and is damped above that height. Large variability in amplitude and phase are found from one observing period to another. The height gradient of the average daytime temperature near 120 km is about 15 K/km. This value is larger than given by some theoretical treatments but is consistent when the energy carried into the region by the semidiurnal tide is allowed for.
Preliminary feasibility of dedicated breast CT with an inverse geometry

In this study we theoretically investigated the minimum scan time of an inverse-geometry dedicated breast CT system that provides sufficient sampling and dose equivalent to mammography without exceeding the limits of source power or detector count rate. The inverse geometry, which utilizes a large-area scanned source and a narrower photon-counting detector, is expected to have improved dose efficiency compared to cone-beam methods due to reduced scatter effects and improved detector efficiency. The analysis assumed the specifications of available inverse-geometry source and detector hardware (SBDX, NovaRay, Inc, Newark CA). The scan time was calculated for a 10, 14, and 18-cm diameter breast composed of 50% glandular / 50% adipose tissue. The results demonstrate a minimum scan time of 6.5, 14.3, and 14.7 seconds for a 10, 14, and 18-cm-diameter breast, respectively. The scan times are comparable to those of proposed cone-beam systems. For all three breast sizes, the scan time was limited by the detector count rate. For example, for the 14-cm-diameter breast, the minimum scan time that met the source power limitation was 1.1 seconds, and the minimum scan time that achieved sufficient sampling was 0.8 seconds. The scan time can be reduced by increasing the detector count rate or area. Effective bowtie filters will be required to prevent detector saturation at the object edges. Overall, the results support preliminary feasibility of dedicated breast CT with an inverse geometry.
IgG: Blocking and mediating anaphylaxis

Abstract Rationale Mice immunized with the T-dependent Ag, goat anti-mouse IgD Ab (GaMD), develop mastocytosis and IgE and IgG anti-goat IgG (GIgG) Ab. Surprisingly, these mice develop IgG/FcγRIII-dependent anaphylaxis, but not IgE/FcϵRI/mast cell-dependent anaphylaxis, when challenged with 100 μg of GIgG. Studies were performed to explain the absence of IgE-mediated anaphylaxis. Methods To test the hypothesis that IgG Ab inhibit IgE-mediated anaphylaxis by blocking GIgG binding to mast cell-associated IgE anti-GIgG Ab, we compared the abilities of 100 vs. 10,000 μg of GIgG to induce mast cell degranulation and anaphylaxis in GaMD-immunized mice in which IgG-dependent anaphylaxis was suppressed by anti-FcγRII/RIII mAb. We also evaluated the ability of polyclonal IgG anti-TNP Ab to suppress TNP-OVA-induced anaphylaxis and mast cell degranulation in IgE anti-TNP mAb-primed mice. Results Both 100 and 10,000 μg of GIgG induced anaphylaxis in otherwise untreated GaMD-primed mice, but only the 10,000 μg dose induced mast cell degranulation (histamine and MMCP1 release) and only the 10,000 μg dose induced anaphylaxis in anti-FcγRII/RIII mAb-treated, GaMD-primed mice. Furthermore, IgG anti-TNP Ab blocked TNP-OVA-induced anaphylaxis in mice primed with IgE anti-TNP mAb. Blocking was overcome by increasing the challenge dose of TNP-OVA. Higher doses of Ag were required to induce IgG-mediated anaphylaxis than IgE-mediated anaphylaxis. Conclusions IgG Ab can block IgE-mediated anaphylaxis by competing for Ag with mast cell-bound IgE Ab and can protect against anaphylaxis induced by relatively low quantities of Ag. However, challenge with a high Ag dose may both overcome the protective effect of IgG blocking Ab and induce IgG-mediated anaphylaxis.
Amino Acid-dependent Transfer RNA Affinity in a Class I Aminoacyl-tRNA Synthetase

Steady-state and transient kinetic analyses of glutaminyl-tRNA synthetase (GlnRS) reveal that the enzyme discriminates against noncognate glutamate at multiple steps during the overall aminoacylation reaction. A major portion of the selectivity arises in the amino acid activation portion of the reaction, whereas the discrimination in the overall two-step reaction arises from very weak binding of noncognate glutamate. Further transient kinetics experiments showed that tRNA(Gln) binds to GlnRS approximately 60-fold weaker when noncognate glutamate is present and that glutamate reduces the association rate of tRNA with the enzyme by 100-fold. These findings demonstrate that amino acid and tRNA binding are interdependent and reveal an important additional source of specificity in the aminoacylation reaction. Crystal structures of the GlnRS x tRNA complex bound to either amino acid have previously shown that glutamine and glutamate bind in distinct positions in the active site, providing a structural basis for the amino acid-dependent modulation of tRNA affinity. Together with other crystallographic data showing that ligand binding is essential to assembly of the GlnRS active site, these findings suggest a model for specificity generation in which required induced-fit rearrangements are significantly modulated by the identities of the bound substrates.
COMPLEMENT FIXATION BY A TWO-COMPONENT ANTIBODY SYSTEM: IMMUNOGLOBULIN G AND IMMUNOGLOBULIN M ANTI-GLOBULIN (RHEUMATOID FACTOR) PARADOXICAL EFFECT RELATED TO IMMUNOGLOBULIN G CONCENTRATION

Complement-mediated lysis of sheep erythrocytes coated with optimal concentrations of rabbit IgG hemolysin was inhibited by euglobulin fractions from the sera of patients with seropositive rheumatoid arthritis. That this was due to direct interaction with the IgG coat on the red cell rather than a nonspecific reaction with complement in the fluid phase was confirmed by controls using cells coated with IgM hemolysin. The inhibitory activity was recovered in purified IgM rheumatoid factor preparations and could be absorbed out with insoluble aggregated human IgG. The inhibitory potency of the rheumatoid factors correlated well with their sheep cell agglutination titers. Inhibition was not the result of physical aggregation of the erythrocytes by rheumatoid factor. Kinetic studies were consistent with the view that rheumatoid factor displaces C1q from its binding to IgG. Paradoxically, at suboptimal sensitizing concentrations of IgG hemolysin, rheumatoid factor enhances the fixation of complement. These results can be interpreted on the basis of the blockage of complement fixation by IgG and its replacement by a relatively weak direct fixation by the IgM rheumatoid factor. Thus, the interaction of RF with IgG generates only a limited ability to fix complement which, when contrasted with the fixation at suboptimal concentrations of IgG hemolysin alone, appears as net enhancement; when this is contrasted with fixation occurring with optimal concentrations of IgG, it appears as net inhibition.