cssi/SciSciGPT-SciSciNet huggingface dataset:
Heterogeneous T cell receptor Vβ gene repertoire in murine interstitial nephritis

Heterogeneous T cell receptor Vβ gene repertoire in murine interstitial nephritis. Anti-tubular basement membrane disease (αTBM) produces T cell-mediated interstitial nephritis in SJL/J mice following immunization with heterologous renal tubular antigen. Initial mononuclear infiltrates appear in vivo after six to eight weeks, with subsequent progression to renal fibrosis and endstage kidney disease. Cultured lymph node derived nephritogenic T cells from these mice react to a small epitopic region of the 3M-1 target antigen and share a common amino acid motif in their Vβ CDR3 regions. We now have used RT-PCR to further characterize the renal expression of T cell receptor (TcR) Vβ gene repertoires during the course of this disease. Individual kidneys with focal mononuclear infiltrates characteristic of early αTBM disease express up to three different TcR Vβ genes; however, the same Vβ genes are not found in all kidneys at the same early stage of injury. DNA sequencing of the Vβ RT-PCR products reveals a heterogeneous population of VDJ recombinations and deduced CDR3 amino acid sequences. Our studies do not support TcR Vβ region gene restriction in histologically-detectable αTBM disease, but are more consistent with a dynamic, organ-specific autoimmune disease, directed at multiple autoantigenic epitopes.
Establishing the diagnosis of HIV infection: new tests and a new algorithm for the United States.

Differentiating HIV-1 from HIV-2 poses another challenge.Almost all screening assays now incorporate antigens to detectboth HIV-1 and HIV-2, but because of cross-reactivity, the HIV-1Western blot is often positive in patients with HIV-2, and no HIV-2conﬁrmatory test is currently approved by the U.S. Food and DrugAdministration (FDA).
The Influence of Thermally-Induced Mesoscale Circulations on Turbulence Statistics Over an Idealized Urban Area Under a Zero Background Wind

The influence of mesoscale circulations induced by urban-rural differential surface sensible heat flux and roughness on convective boundary-layer (CBL) flow statistics over an isolated urban area has been examined using large-eddy simulation (LES). Results are analyzed when the circulations influence the entire urban area under a zero background wind. For comparison, the CBL flow over an infinite urban area with identical urban surface characteristics under the same background meteorological conditions is generated as a control case (without circulations). The turbulent flow over the isolated urban area exhibits a mix of streaky structure and cellular pattern, while the cellular pattern dominates in the control case. The mixed-layer height varies significantly over the isolated urban area, and can be lower near the edge of the urban area than over the rural area. The vertical profiles of turbulence statistics over the isolated urban area vary horizontally and are dramatically different from the control case. The turbulent kinetic energy (TKE) sources include wind shear, convergence, and buoyancy productions, compared to only buoyancy production in the control case. The normalized vertical velocity variance is reduced compared to the control case except in the central urban area where it is little affected. The low-level flow convergence is mainly responsible for the enhanced horizontal velocity variance in the central urban area, while wind shear is responsible for the additional local maximum of the horizontal velocity variance near the middle of the CBL outside the central area. Parameterizations in the prognostic equation for TKE used in mesoscale models are evaluated against the LES results over the isolated urban area. We also discuss conditions under which the urban-induced circulations occur and when they may affect the entire urban area. Given that urban-induced circulations can influence the entire urban area within hours for an urban area of a realistic size, it is inappropriate to directly apply empirical relations of turbulence statistics derived under horizontally-homogenous flow conditions to an urban area.
Thermal analysis by diffuse reflectance Fourier transform infrared spectroscopy-mass spectrometry

Abstract A new thermal analysis technique is introduced that combines diffuse reflectance Fourier transform infrared spectroscopy and mass spectrometry to monitor temperature-dependent structural changes in solids while simultaneously detecting volatile reaction products. The apparatus is described in detail and applications of the instrument to studies of the thermal degradation of polystyrene and the dehydroxylation of silica are discussed.
Thermodynamics of metal cation binding to apoconcanavalin A

Abstract The thermodynamics of the binding of Mn +2 , Co +2 , Ni +2 , Zn +2 , and Cd +2 to demetallized concanavalin A (apoCon A) in 0.02 M dimethylglutaric-NaOH buffer (pH 5.0–5.8 and pH 6.9) was determined from titration calorimetry measurements at 298.2 K and at pH 5.0 from 288.2 to 308.2 K. The apparent binding constants decrease with pH, resulting from competitive protonation of the histidine 24 ligand at the binding site. The binding constants to deprotonated apoCon A increase in the order, Ni +2 > Co +2 > Zn +2 > Cd +2 > Mn +2 at pH ⪯ 5.6, the same as their crystal field stabilization energies with the energies of Zn +2 , Cd +2 , and Mn +2 = 0. At 298.2 K and pH ⪯ 5.8, the binding entropies are all approximately 200 J K −1 mol −1 and the binding enthalpies are lower for Co +2 and Ni +2 which results from negative contributions of the crystal field stabilization energies. At pH 6.9, where differential scanning calorimetry shows that apoCon A unfolds at 311.2 K, the apparent binding constants decrease to minimum values. Concanavalin A, however, unfolds at 363.2 K and its free energy difference between the unfolded and folded states is 32 ± 2 kJ mol −1 greater than that of apoCon A. At 298.2 K, the free energy difference between the unfolded and folded states of concanavalin A and apoCon A is the same as the change in the free energy upon Mn +2 and Ca +2 binding to apoCon A.
Contribution of junctional conductance to the cellular voltage-divider ratio in frog skins

It has been suggested that distribution of lateral interspace resistance in association with a highly conductive junction can significantly affect the measurement of outer membrane(o)/epithelial(t) voltage divider ratios (Fo=δVo/δVt), thereby leading to erroneous inferences regarding the outer membrane fractional resistance [fRo=Ro/Rc=Ro/(Ro+Ri)], whereRo andRi are the outer and inner cell membrane resistance respectively andRc is the total cell membrane resistance. We present here experimental evidence for this point of view. During seasons when frog skins were highly permeable to Cl, transepithelial conductancegt often exceeded 2 mS/cm2. High concentrations of external amiloride rapidly blocked cellular transport, butgt initially remained high andFo remained appreciably less than 1.0. These values ofFo were found here to result from low junctional resistanceRj: increase ofRj, either gradually following the administration of amiloride, or abruptly with external replacement of Cl by other anions, was associated with increase ofFo to near unity, without effect on the membrane potential or significant change in the short-circuit current. Experimental results following amiloride validated a simple equivalent circuit model predicting near-linear increase inFo with progressive decrease ingt and led to plausible values ofRj and lateral space resistanceRl. The possible influence of the paracellular resistance pattern on the evaluation of cell membrane resistances from voltage divider ratios is discussed.
The Human Food Niche in the Levant Over the Past 150,000 Years

Archaeologists have tended to accept Flannery's (1969) broad spectrum revolution (BSR) as a general phase in an evolutionary sequence of subsistence changes leading to the appearance of domestication economies. Previous partial tests of the Flannery model in both hemispheres have tended to support it, especially those aspects of it that predict increasing subsistence diversity over time and increases in the relative intensity of food procurement. Phillip Edwards has recently claimed, however, that the BSR is not documented in Levantine archaeofaunal data and that its generality as a phase in the domestication process in that region can therefore be called into question. We re-analyzed Edwards's data using a simulation approach and came to the conclusion that there was, in fact, considerable support for the BSR. We attribute the disparity between our results and those of Edwards to the way in which diversity is measured.
Effects of retinoic acid on expression of the transformed phenotype in C6 glioma cells.

Abstract Retinoic acid (RA) inhibited the growth and induced morphological changes in C6 rat glioma cells. The effects of RA on growth rate became apparent after 48 hr and were concentration-dependent and reversible. There was a 60% inhibition of growth using 10 −5 RA, which increased at low serum concentration to over 90% inhibition and was minimized at high concentration of serum. RA did not change the saturation density of the cells. The morphology of C6 cells, was altered from its normal pattern of randomly orienteded spindle shaped cells, to cells which aligned to form palisades of fibroblast-like cells. Biochemical analysis of the cells showed no significant change in the activities of several lysosomal hydrolyses or the level of total protein in RA-treated cells compared to control cells. There was, however, a significant decrease in the activity of ornithine decarboxylase early during the treatment with RA, and an increase in the levels of fibronectin secreted into the media by the RA-treated cell. These results suggest that RA can suppress the expression of the transformed phenotype of glioma cells.
Location-Aware Routing Protocol for Underwater Acoustic Networks

Autonomous underwater vehicles (AUVs) are being used in ever larger numbers, and the rise in the simultaneous use of multiple AUVs is introducing challenging communication problems best addressed in the realm of mobile, ad hoc networking (MANET). This paper describes location-aware source routing (LASR), our modification of the dynamic source routing (DSR) protocol to add location awareness and link quality metrics. A new protocol is needed because of the unique difficulties of underwater networking: radio links do not work through water, and the acoustic links that are used instead have much lower data-rates and much higher latency. Specifically designed for use in underwater acoustic networks, LASR is explained, and initial simulation results are presented to show that the new protocol performs better than two existing techniques.
Response to dexamethasone in psychotic depression

The utility of the dexamethasone suppression test (DST) in the diagnosis of psychotic depression was examined by comparing the responses of 11 psychotic and 18 nonpsychotic depressed inpatients. Nine of 11 psychotic patients (81.8%) and 10 of 18 nonpsychotic patients (55.6%) showed nonsuppression (nonsignificant). Using the 0800h cortisol level alone, we found that significantly more psychotic patients (7 of 11; 63.6%) than nonpsychotic patients (3 of 18; 16.7%) showed nonsuppression. Nonsuppression at 0800h postdexamethasone may be a useful biologic marker for patients with psychotic depression. Implications of these data for the nosologic status of psychotic depression are discussed.
High titers of Epstein-Barr virus antibodies in adult patients with lymphocytic interstitial pneumonitis associated with AIDS.

Lymphocytic interstitial pneumonitis (LIP) was classically described by Carrington and Leibow in 1966 in non-AIDS patients (1). This pathological description of diffuse lymphocytic infiltration of the interstitium was later associated with various autoimmune disorders such as Sjogren's syndrome, thyroiditis and others (2). Since the beginning of the AIDS epidemic several reports described the common finding of LIP in children infected with human immume deficiency virus (HIV) (3). Less commonly, LIP was reported in adults, mostly Haitians, with AIDS or AIDS-related complex (4--6). While the pathological and radiological manifestations are well described, little is known about the pathogenesis of this disorder. There is some evidence in children with AIDS that Epstein-Barr virus (EBV) is associated with LIP. Feckler and associates (7) reported the detection of EBV-DNA genome in saliva and lung tissue of a child with LIP and Adinman and colleagues (8) reported similar findings in eight additional AIDS-children with LIP. In order to explore the possible etiologic role of EBV in HIV-seropositive adults with LIP we measured the EBV serology in the peripheral blood of five patients with LIP and compared them to 19 HIV-positive patients without LIP.
Choosing Outcome Measures in Systematic Reviews: Critical Challenges

There are a number of challenges facing those who set out to conduct systematic reviews of intervention effects in the social sciences. These challenges include formulation of a review problem, gat...
Second-Order Stark Shifts in the Optical Spectrum of Anthracene in a Naphthalene Crystal

Abstract The O—O band of the spectral transition to the 1B2u excited state of anthracene in a naphthalene host crystal has been studied by Stark modulation. The transition shifts to lower energy in the electric field with a quadratic field strength dependence. Stark shifts normalized to an applied field of 105 V/cm along the a*, b, and c* axes were measured to be 4.8 ± 1.3, 15.2 ± 1.7, and 44.1 ± 3.0 × 10−3cm−1. The elements of the polarizability difference tensor between the ground and excited states have been computed from these shifts for a series of local field approximations. The closest agreement between the resulting trace of the polarizability difference tensor and previous experimental measurements of this quantity is obtained with the less anisotropic local fields. The use of an “exact point dipole” local field yields the poorest agreement and this is suspected to result from the breakdown of the point dipole approximation. The most logical choice of the local field tensor [calculated from the g...
Inhibition of thiazopyr metabolism in plant seedlings by inhibitors of monooxygenases

Metabolism of the herbicide thiazopyr [methyl 2-(difluoromethyl)-5-(4,5-dihydro-2-thiazolyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-3-pyridinecarboxylate] was examined in young seedlings of redroot pigweed, grain sorghum, sunflower, corn and soybean. As previously observed with rat liver microsomes plants predominantly metabolized thiazopyr via oxidation reactions. Sulfur and carbon atoms in the thiazoline ring were the primary sites of plant oxygenases. De-esterification was also identified as an important pathway of transformations in plants. Although similar pathways of thiazopyr metabolism were observed among plants, our data indicated species differences in rates of thiazopyr degradation. Among species examined, pigweed (Amaranthus retroflexus L.) showed the fastest metabolism. Thiazopyr metabolism in pigweed was significantly inhibited by several cytochrome P450 monooxygenase inhibitors, among which tetcyclacis (TET) and piperonyl butoxide (PBO) were the most inhibitory. Thiazopyr metabolism in pigweed was not inhibited by organophosphates, known inhibitors of esterases. The results suggest that thiazopyr metabolism in plants is predominantly mediated via plant monooxygenases.
Anomalous origins of the right common carotid andright and left subclavian arteries associated with eisenmenger's complex

Summary 1. A case of anomalous origins of the right common carotid and right and left subclavian arteries associated with Eisenmenger's complex in a Mongolian idiot, is presented. 2. Some embryological considerations are reviewed in an attempt to explain the probable source of the anomalous origins of these vessels. 3. Theoretical considerations of the direction of blood flow are discussed in an attempt to correlate the clinical picture with the anatomical findings.
Matrix isolation study of the vacuum ultraviolet photolysis of allene and methylacetylene. Vibrational and electronic spectra of the species C3, C3H, C3H2, and C3H3

Upon hydrogen-discharge photolysis of normal or deuterium-substituted allene or methylacetylene in an argon or a nitrogen matrix at 14°K, infrared absorptions of all of the C3Hn species with n < 4 appear. A hydrogen-deformation fundamental of C3H2 has been identified in the far infrared. Infrared studies of the partially deuterium- substituted methylacetylenes indicate that extensive photoisomerization occurs. The observed products are consistent with those predicted using the previously postulated gas-phase photolysis mechanism. The ultraviolet spectrum of C3H3 corresponds closely with that characteristic of the gas-phase molecule. Comparison of the spectrum between 1900 and 4000 A of photolyzed methylacetylene with that of matrix-isolated graphite vapor has indicated that any new electronic transition of C3 in this region must be weak.
Intermittent chaos, self-organization, and learning from synchronous synaptic activity in model neuron networks

Abstract Self-organization of frequencies is studied by using model neurons called VCONs (voltage-controlled oscillator neuron models). These models give direct access to frequency information, in contrast to all-or-none neuron models, and they generate voltage spikes that phase-lock to oscillatory stimulation, similar to phase-locking of action potentials to oscillatory voltage stimulation observed in Hodgkin-Huxley preparations of squid axons. The rotation vector method is described and used to study how networks synchronize, even in the presence of noise or when damaged; the entropy of ratios of phases is used to construct an energy function that characterizes organized behavior. Computer simulations show that rotation numbers (output frequency/input frequency) describe both chaotic and nonchaotic behavior. Learning occurs when synaptic connections strengthen in response to stimulation that is synchronous with cell activity. It is shown that intermittent chaotic firing is suppressed and simple stable responses are enhanced by such learning in VCON networks. This analysis provides a rigorous basis for further investigation of the ideas of Wiener [Wiener, N. (1961) Cybernetics (MIT Press, Cambridge, MA), p. 191] on the origin of slow brain waves due to "the pulling together of frequencies."
Analysis of Flow Angularity Repeatability Tests in the NTF

An extensive data base of flow angularity repeatability measurements from four NTF check standard model tests is analyzed for statistical consistency and to characterize the results for prediction of angle-of-attack uncertainty for customer tests. A procedure for quality assurance for flow angularity measurements during customer tests is also presented. The efficacy of the procedure is tested using results from a customer test.
Characterization of the calcination process of yttria

Abstract A complete characterization of the calcination of precipitates obtained from a continuous operation was carried out in this study. The precipitate was obtained by reacting yttrium nitrate and ammonia solutions in a MSMPR reactor. It precipitated out as yttrium hydroxide nitrate hydrate, which has the general form Y 2 (OH) 6- x (NO 3 ) x · y H 2 O. This compound decomposed in consecutive steps with the last reaction occurring at 525°C. The calcination process was characterized by chemical analysis, X-ray diffraction analysis, DTA and TG. In addition, the physical characteristics of calcined powders, such as specific surface area, particle size distribution, pore volume distribution, X-ray crystallite size and conversion were measured as a function of calcination temperature and time. Finally, the kinetics of the reduction of surface area, the growth of crystallite size and conversion were also examined.
Optimization of physiological parameter for macroscopic modeling of reacted singlet oxygen concentration in an in-vivo model

Singlet oxygen (1O2) is generally believed to be the major cytotoxic agent during photodynamic therapy (PDT), and the reaction between 1O2 and tumor cells define the treatment efficacy. From a complete set of the macroscopic kinetic equations which describe the photochemical processes of PDT, we can express the reacted 1O2 concentration, [1O2]rx, in a form related to time integration of the product of 1O2 quantum yield and the PDT dose rate. The production of [1O2]rx involves physiological and photophysical parameters which need to be determined explicitly for the photosensitizer of interest. Once these parameters are determined, we expect the computed [1O2]rx to be an explicit dosimetric indicator for clinical PDT. Incorporating the diffusion equation governing the light transport in turbid medium, the spatially and temporally-resolved [1O2]rx described by the macroscopic kinetic equations can be numerically calculated. A sudden drop of the calculated [1O2]rx along with the distance following the decrease of light fluence rate is observed. This suggests that a possible correlation between [1O2]rx and necrosis boundary may occur in the tumor subject to PDT irradiation. In this study, we have theoretically examined the sensitivity of the physiological parameter from two clinical related conditions: (1) collimated light source on semi-infinite turbid medium and (2) linear light source in turbid medium. In order to accurately determine the parameter in a clinical relevant environment, the results of the computed [1O2]rx are expected to be used to fit the experimentally-measured necrosis data obtained from an in vivo animal model.
Comments on group theoretical analysis of NQR spectra of crystals

The use of generating function methods for the number of NQR lines of crystals exhibiting distortion is outlined. The intensity ratios of NQR lines can be obtained using a double coset method.
On the locus of the stimulus familiarization effect in young children

Abstract Twenty kindergarten S s received 50 reaction time trials. They withdrew their finger from a button as soon as 1 of 2 colored lights came on. 1 color occurred on the familiarization trials 1–20 and a 50:50 random sequence of that familiar color and a novel one was given on the last 30. Faster speeds to novel than to familiar indicate that the stimulus familiarization effect is not attributable to competing attending responses learned during the familiarization which then interfere with responding to the familiar stimulus during test trials, as has been suggested. Thirty-two kindergarten children observed 1 color for 3 seconds on each of 20 trials and then performed in a discriminative reaction time task in which the familiarized color and a novel one each serve as the signal to initiate (immediately withdraw the finger from a starting button) and execute (press that 1 of 2 buttons having the same color as the signal light) a discriminative response. One-half the S s had sequences of novel and familiar stimuli with a tendency to alternate (TA) 75% of the time; for the other one-half the stimuli repeated (TR) 75% of the time. Initiation, but not execution, speeds were greater to the novel than to the familiar stimulus. Execution, but not initiation, speeds showed the change effect (CE) (found by Cantor and Cantor in two studies) with the TA sequences and a reverse CE with the TR sequences. The results show that the CE is an artifact and also that the hypothesis of surprisingness of the novel stimulus is probably false.
Leveraging probabilistic season and location context models for scene understanding

Recent research has shown the power of context-aware scene understanding in bridging the semantic gap between high-level semantic concepts and low-level image features. In this paper, we present a new method to exploit nonvisual context information from the season and location proximity in which pictures were taken to facilitate region (object) annotation in consumer photos. Our method does not require precise time and location from the capture device or user input. Instead, it learns from rough location (e.g., states in the US) and time (e.g., seasons) information, which can be obtained through picture metadata automatically or through minimal user input (e.g., grouping). In addition, the visual context within the image is obtained by analyzing the spatial relationships between different regions (objects) in the scene. Both visual and nonvisual context information are fused using a probabilistic graphical model to improve the accuracy of object region recognition. Our method has been evaluated on a database that consists of over 10,000 regions in more than 1000 images collected from both the Web and consumers. Experimental results show that incorporating the season and location context significantly improves the performance of region recognition.
More Accurate Approximation of J -Integral Equation for Evaluating Fracture Resistance Curves

Accurate estimate of the J integral is required in a valid experimental evaluation of J-based fracture resistance curves for ductile materials. The fracture toughness test standard ASTM E1820 allows a basic method and a resistance curve method to be used experimentally to evaluate the J values via standard specimens. The basic method obtains J estimates using the η factor method that was developed for a stationary crack. The resistance curve method obtains crack growth corrected J estimates using an incremental equation that was proposed by Ernst (“Estimation on J-Integral and Tearing Modulus T from a Single Specimen Test Record,” Fracture Mechanics: Thirteenth Conference, ASTM STP 743, 1981, pp. 476–502) for a growing crack and has been accepted as the most accurate equation available for about three decades. Recently, Neimitz (“The Jump-Like Crack Growth Model, the Estimation of Fracture Energy and JR Curve,” Eng. Fract. Mech., Vol. 75, 2008, pp. 236–252), and Kroon (“A Probabilistic Model for Cleavage Fracture with a Length Scale-Parameter Estimation and Predictions of Growing Crack Experiments,” Eng. Fract. Mech., Vol. 75, 2008, pp. 2398–2417) presented two different approximate equations for the J-integral, which they proposed as more accurate than the Ernst equation. Therefore, further investigation is needed to determine a truly accurate approximation for the J-integral equation. With this objective, the present paper proposes different mathematical and physical models to approximate the J-integral equation. The physical models are developed in terms of the deformation theory and the jump-like crack growth assumption. Relations between the proposed models and the existing equations are identified. Systematic evaluations of the proposed models are then made using a theoretical procedure of J-R curves for both low and high strain hardening materials, and using experimental data from an actual single edge-notched bend specimen made of HY80 steel. Accuracy of the proposed models is determined, and a more accurate approximation of J-integral equation is thus suggested for J-R curve testing.
A microincinerative study of normal and starving Amoeba proteus

T HIS work demonstrates, by microincinerative techniques, the distribution of minerals in the normal and starved Amoeba proteus. The possibility that the results obtained may elucidate the metabolism of protein as well as that of minerals, is discussed. Materials and Methods.-The manner of handling, e.g., culturing, embedding of the amoebas, has been described [2]. The amoebas which had been fixed in a mixture of 9 parts of absolute ethanol and 1 part of neutral formalin were embedded in paraffin, cut at 4 p, and mounted on cover slips. Both the mounting and incineration of the sections were carried out essentially according to the procedure described by Scott [5]. Incineration was done in a Huppert’s Mighty Midget Oven. The temperature was gradually elevated 60” to 70°C every 5 minutes until 650°C was reached, at which time the heating was discontinued. After cooling, the covers slips were placed on slides and sealed with a mixture of equal parts of paraffin, beeswax, and resin. Alternate sections of the serially sectioned amoebas were used as cytologic controls and stained with either Heidenhain’s hematoxylin or toluidine blue [2]. Observations of the incinerated material were made under both brightfield illumination (KBhler) and darkfield illumination. For the latter, either a darkfield condenser, Leitz D 0.8, or a condenser stop, was used in conjunction with an objective diaphragm. Results.-The cytological detail of the incinerated sections compares favorably with that of the alternate sections stained with Heidenhain’s hematoxylin or with toluidine blue (cf. Figs. 1 and 2). Under darkfield illumination, one can observe that the surface of the incinerated sectioned normal amoeba displays an alignment of coarse or fine ash, or both. The cytoplasmic matrix is seen as a reticulum-like pattern of fine ash delineating the vacuoles. Superimposed on this network are occasional small, coarse ash droplets. The prominent larger, coarse ash bodies seen, are the mineral residues of the refractive bodies (Fig. 3). Incinerated residue of the other cytoplasmic inclusions (i.e. crystals, mitochondria, and alpha granules) cannot be identified per se but are probably observed in the cytoplasmic ash, described above. The nucleus can be easily identified by the conspicuous ash pattern of its numerous nucleoli which appear as discrete, refractile masses of high mineral concentration
EEG diagnosis of nonconvulsive status epilepticus: generalized periodic patterns--status or not?

The gold standard for the diagnosis of nonconvulsive status epilepticus (NCSE) is EEG [1,2]. Studies on NCSE in the literature often imply that the EEG diagnosis of NCSE is straightforward [3,4]. I...
Studies on the non-specific binding of ribosomal RNA to Escherichia coli ribosomes☆

Abstract Ribosomal RNA (rRNA) binds to ribosomes which contain small pieces of endogenous messenger RNA, when assayed by sticking to Millipore filters. This association is lost when the messenger RNA is removed by incubation of the ribosomes in buffer containing 10−4 m -Mg2+, but can be recovered by the addition of turnip yellow mosaic virus (TYMV) RNA. TYMV RNA promotes the binding of equal masses of 16 and 23 s rRNA to ribosomes. The incubation in 10−4 m -Mg2+ buffer, which destroys the ability of ribosomes to bind rRNA, increases their ability to bind TYMV RNA fivefold. Free rRNA does not compete with ribosomes for ribosome-binding sites in TYMV RNA. These results suggest that the binding of messenger RNA to free rRNA does not reflect the binding of messenger RNA to ribosomes.
Analyzing motorists’ responses to temporary signage in highway work zones

For decades, the importance of highway work zone safety has increased considerably with the continual increase in the number of highway work zones present on highways for repairs and expansion. Rural work zones on two-lane highways are particularly hazardous and cause a significant safety concern due to the disruption of regular traffic flow. In this study, researchers determined motorists’ responses to warning signs in rural, two-lane highway work zones. The researchers divided vehicles into three classes (passenger car, truck, and semitrailer) and compared the mean change in speed of these classes based on three different sign setups: portable changeable message sign (PCMS) OFF, PCMS ON with the message of Slow Down, Drive Safely, and a temporary traffic sign (W20-1, “Road Work Ahead”). Field experiments were conducted on two two-lane work zones with flagger control. Statistical analyses were performed to determine whether there was a significant interaction between motorists’ responses and the sign setups. Data analysis results show that a visible PCMS, either turned on or off, was most effective in reducing truck speeds in rural, two-lane work zones. The temporary traffic sign (W20-1) was more effective in reducing the vehicle speeds of passenger car and semitrailer. Results of this research project will help traffic engineers to better design the two-lane work zone setup and take necessary safety countermeasures to prevent vehicle crashes.
Dynamics of ultrasonic and electrostatic friction modulation for rendering texture on haptic surfaces

Surface haptic devices modulate the friction between the surface and the fingertip, and can thus be used to create a tactile perception of surface features or textures. We present modeling and experimental results on both ultrasonic and electrostatic surface haptic devices, characterizing their dynamics and their bandwidth for rendering haptic effects.
Steady state power-law creep in heterogeneous alloys with coarse microstructures

Abstract In many heterogeneous engineering alloys of a relatively coarse phase distribution where non-local effects due to such phases are unimportant and where inelastic deformation inside these phase domains can be appropriately viewed by continuum concepts, the overall steady creep behavior of the alloy can be obtained by the use of the well-known self-consistent theory for polycrystals and composites, in a piece-wise linear and incremental approach—provided the creep constitutive behavior for each of the constituent phases is known.
Reconstruction Techniques for Sparse Multistatic Linear Array Microwave Imaging

Sequentially-switched linear arrays are an enabling technology for a number of near-field microwave imaging applications. Electronically sequencing along the array axis followed by mechanical scanning along an orthogonal axis allows dense sampling of a two-dimensional aperture in near real-time. The Pacific Northwest National Laboratory (PNNL) has developed this technology for several applications including concealed weapon detection, groundpenetrating radar, and non-destructive inspection and evaluation. These techniques form three-dimensional images by scanning a diverging beam swept frequency transceiver over a two-dimensional aperture and mathematically focusing or reconstructing the data into three-dimensional images. Recently, a sparse multi-static array technology has been developed that reduces the number of antennas required to densely sample the linear array axis of the spatial aperture. This allows a significant reduction in cost and complexity of the linear-array-based imaging system. The sparse array has been specifically designed to be compatible with Fourier-Transform-based image reconstruction techniques; however, there are limitations to the use of these techniques, especially for extreme near-field operation. In the extreme near-field of the array, back-projection techniques have been developed that account for the exact location of each transmitter and receiver in the linear array and the 3-D image location. In this paper, the sparse array technique will be described along with associated Fourier-Transform-based and back-projection-based image reconstruction algorithms. Simulated imaging results are presented that show the effectiveness of the sparse array technique along with the merits and weaknesses of each image reconstruction approach.
Differential expression of thromboxane A synthase and prostaglandin H synthase in megakaryocytic cell line

We determined the expression of isoforms of prostaglandin H synthase (PGHS) and thromboxane A synthase (TXAS) in a human megakaryocyte cell line (MEG-01. The basal levels of full-length TXAS mRNA and the 60 kDa TXAS protein were high when compared to those of PGHS-1 and PGHS-2 in uninduced cells. Despite a high TXAS level, uninduced MEG-01 cells synthesized only a small amount of thromboxane A2 (TXA2) due to limited PGHS-1 or PGHS-2 expressions. Following PMA induction there was little change in TXAS. PGHS-2 mRNA was significantly increased at only 3 h of PMA treatment and the level declined rapidly, whereas PGHS-1 mRNA and protein levels were concordantly stimulated. Induction of PGHS-1 reached plateau on day 3 of PMA treatment. Analysis of arachidonate metabolism in cells induced by PMA for 3 and 5 days showed a high level of PGH2 synthesis which exceeded the TXAS capacity for TXA2 synthesis. Only traces of PGHS-2 mRNA and alternate-spliced TXAS mRNA were detected in human platelets. We conclude that TXAS and PGHS are differentially expressed in MEG-01 during PMA-induced differentiation.
Neutrophil degranulation and the effects of phosphodiesterase inhibition.

Background. Neutrophils play a major role as the first line in host defense after exposure to bacterial products. However, an exaggerated inflammatory response characterized by overwhelming neutrophil activation can be injurious to the host. Pentoxifylline (PTX), a nonspecific phosphodiesterase inhibitor, has been shown to attenuate neutrophil oxidative burst and decrease proinflammatory mediator synthesis. We hypothesized that PTX down-regulates neutrophil activation by decreasing the surface expression of both CD35 and CD66b, two markers of neutrophil degranulation. Materials and methods. Venous blood was obtained from three healthy volunteers. Whole blood was incubated with HBSS (control), f-methionyl-leucyl-phenylalanine (fMLP, 1 μM/L), PTX (2 mM/L), or fMLP + PTX. CD35 and CD66b expression were measured by flow cytometry. Results. fMLP treatment caused a significant increase in CD35 and CD66b expression of when compared to controls (P < 0.01). PTX treatment revealed expression of both markers comparable to the control group. A 38% decrease in CD35 (64 ± 12 versus 100; P < 0.01) and a 52% decrease in CD66b (48 ± 7 versus 100; P < 0.01) expression were demonstrated in the fMLP + PTX group when compared to fMLP alone. Conclusion. In addition to the known effects of PTX on neutrophil oxidative burst, PTX also affects neutrophil degranulation, an essential step in enzyme release and subsequent tissue injury. These findings may have clinical relevance in the treatment of disease processes due to inflammation in which primed neutrophils play a role.
Stage efficiency in the analysis of thermochemical water decomposition processes

The procedure for analyzing thermochemical water-splitting processes using the figure of merit is expanded to include individual stage efficiencies and loss coefficients. The use of these quantities to establish the thermodynamic insufficiencies of each stage is shown. A number of processes are used to illustrate these concepts and procedures and to demonstrate the facility with which process steps contributing most to the cycle efficiency are found. The procedure allows attention to be directed to those steps of the process where the greatest increase in total cycle efficiency can be obtained.
Has the erosion of the medical marketplace ended

This paper updates tests of the validity of three models of medical price inflation: a standard model, in which changes in demand press against inelastic supply; a dynamic version of the standard model, in which high levels of insurance induce high rates of product innovation and development; and a model of increasing inefficiency, in which consumers have weak incentives to search out efficient suppliers. Earlier statistical support for the third model has weakened, which provides some evidence that the regulatory and competitive initiatives of the last decade are having their intended effects. But time series measures of medical prices upon which the statistical evidence relies have important methodological problems, so other types of evidence are useful. Trends in expenditure in other countries and in HMOs suggest that the most important explanation of medical price inflation is the dynamic version of the standard model, although the other models have some validity as well.
Spirocyclopropane formation and rearrangement in the thermal and photochemical decomposition of 1-pyrazolines from 9-diazofluorene and bicyclic[2.2.1]olefines

Abstract The 1-pyrazolines formed by the photochemical and/or thermal cycloaddition of 9-diazofluorene to norbornadiene and norbornene were isolated and submitted to thermal and photochemical decomposition. The exo 1-pyrazoline from norbornadiene rearranges thermally to 2-(9-spirofluorenylidene)bicyclo[3.2.1]octadiene in high yields. Photolysis of the same pyrazoline however leads to the formation of the “normal” spirocyclopropane, which in turn can be thermally converted to the same bicyclic octadiene. The formation of the rearranged product is thought to be consistent with a mechanism involving a stabilized zwitterion and a cis divinylcyclopropane as intermediates. On photolysis in neat norbornadiene, 9-diazofluorene is converted in high yield to the 1,3 addition product—the 1-pyrazoline. However, when the irradiation was carried out in ether solution, in the presence of large excess of olefin, the major products isolated were 9,9′-bifluorenyl and 9,9′,9′,9″-terfluorenyl. These results add weight to the possibility of pyrazoline formation before its conversion to cyclopropane in many other analogous reactions between diazoalkanes and olefins which were widely interpreted as carbene addition to alkenes.
Fibroblast Growth Factor-binding Protein Is a Novel Partner for Perlecan Protein Core

Perlecan, a widespread heparan sulfate proteoglycan, functions as a bioactive reservoir for growth factors by stabilizing them against misfolding or proteolysis. These factors, chiefly members of the fibroblast growth factor (FGF) gene family, are coupled to the N-terminal heparan sulfate chains, which augment high affinity binding and receptor activation. However, rather little is known about biological partners of the protein core. The major goal of this study was to identify novel proteins that interact with the protein core of perlecan. Using the yeast two-hybrid system and domain III of perlecan as bait, we screened ∼0.5 106cDNA clones from a keratinocyte library and identified a strongly interactive clone. This cDNA corresponded to FGF-binding protein (FGF-BP), a secreted protein previously shown to bind acidic and basic FGF and to modulate their activities. Using a panel of deletion mutants, FGF-BP binding was localized to the second EGF repeat of domain III, a region very close to the binding site for FGF7. FGF-BP could be coimmunoprecipitated with an antibody against perlecan and bound in solution to recombinant domain III-alkaline phosphatase fusion protein. Immunohistochemical analyses revealed colocalization of FGF-BP and perlecan in the pericellular stroma of various squamous cell carcinomas suggesting a potential in vivo interaction. Thus, FGF-BP should be considered a novel biological ligand for perlecan, an interaction that could influence cancer growth and tissue remodeling.
Duplex-guided balloon angioplasty of failing or nonmaturing arterio-venous fistulae for hemodialysis: a new office-based procedure.

Objective Unquestionably, the federal government has created financial incentives for vascular interventionists to perform procedures in their offices rather than in a hospital setting. While office venous ablations have been widely embraced by the vascular community, those involving the arterial system have not. One important reason may be related to the cost of the fluoroscopic equipment. Herein, we report on 32 office-based duplex scan-guided balloon angioplasty cases for failing or nonmaturing arteriovenous (AV) access. Patients and Methods Twenty-five patients (14 males; 11 females; mean age 65.1 ± 9.11) with chronic renal insufficiency underwent 32 office-based ultrasound scan-guided balloon angioplasties of their autologous AV fistulas. Twenty-seven procedures were performed in fistulas that did not mature while the remaining five were performed in failing AV accesses. The indications for these procedures were severe stenoses (>70%) as measured by color duplex scan and confirmed by peak systolic velocity (PSV) step-up >3. Preoperative duplex scan-derived mean volume flows (VFs) and highest stenotic PSV were recorded and compared with postoperative findings. Access site puncture and cannulation with short sheath, wire, and balloon advancement and inflation were guided by duplex scan only. A comparison of revenue for hospital-based vs office-based procedures was performed. Results All procedures were successfully completed without fluoroscopy and contrast material. There were no systemic complications. One patient (3%) developed an arm hematoma due to focal vein rupture which was controlled by a hand compression for 20 minutes. An additional patient (3%) had a focal intraluminal dissection not obstructing the flow. Comparison of preoperative mean VF (350 ± 180 mL/minute) and postoperative mean VF (933 ± 332 mL/minute) demonstrated a statistically significant increase with P P Conclusion This early experience suggests that office-based endovascular repair of AV access under duplex scan-guidance is feasible and safe. The superficial location of AV access facilitates duplex scan visualization. This proposed approach averts contrast material use and radiation exposure. Finally, it appears to be financially more lucrative than the same hospital-based procedures.
THE INFLUENCE OF WATER ON THE BEHAVIOUR OF A KEY BLOCK

In this study, the failure modes of a wedge due to impact of a water jet were examined in a physical model. The water pressures subseqeuntly developed along the block's planar joint faces were measured and their magnitudes examined in relation to the overall wedge stability. Relationships between wedge and jet orientation were investigated for the potential movement of the block, and water penetrating depths along discontinuity surfaces were observed. The results of the model tests were compared with a graphical stability analysis plotted on stereographic projection. The results suggest that water impinging on the surface of a wedge can generate locally high joint water pressures on the block faces with a serious destabilizing effect. As a product of this work, suggestions are offered for improving the stability of rock blocks impacted by a water jet. Consideration of these results for existing dams that display abutment wedges can help in promoting safety and optimizing treatment costs. This paper was presented at the 34th U.S. Symposium on rock mechanics, 27-30 June 1993, University of Wisconsin-Madison. For the covering abstract see IRRD 863389.
Extracorporeal membrane oxygenation in infants: angiographic and parenchymal evaluation of the brain with MR imaging.

The authors report their preliminary experience with intracranial three-dimensional Fourier transform magnetic resonance (MR) angiography and T2-weighted MR imaging of the brain parenchyma in 15 neonates less than 1 week old after extracorporeal membrane oxygenation (ECMO) with permanent ligation of the right common carotid artery and internal jugular vein, four 1-year-old infants after ECMO with carotid ligation, and four neonates less than 1 week old after ECMO with reanastomosis of the same artery. MR angiography was technically satisfactory in 20 of the 23 patients and documented patency of the right internal carotid artery proximal to the ophthalmic artery in nine of 16 patients with permanent carotid ligation and in all four patients with reanastomosis. This study suggests MR angiography is feasible in newborns and infants and that, in combination with parenchymal MR imaging, it provides a sensitive, noninvasive method to assess vessel patency and follow cerebrovascular and parenchymal changes in in...