cssi/SciSciGPT-SciSciNet huggingface dataset:
Design for a contained inductively coupled plasma/D-C arc atomic emission spectrometer at the Savannah River plant

The atomic emission spectroscopy laboratory of the Savannah River Plant, in Aiken, South Carolina, has been in operation for over 30 years. Routine analytical methods and instrumentation are being replaced with current technology. Laboratory renovation will include the installation of contained dual-excitation sources (inductively coupled plasma and D-C arc) with a direct-reading spectrometer. The instrument will be used to provide impurity analyses of plutonium, uranium, and other nuclear fuel cycle materials.
Adsorption and reaction of thiophene on α-Mo2C(0001)

Abstract Thiophene adsorbs reversibly and irreversibly on α-Mo2C(0 0 0 1). Irreversible thiophene adsorption results in decomposition to surface C, surface S, and gaseous dihydrogen. The chemical states of the carbon and sulfur as identified by X-ray photoelectron spectroscopy are carbidic and sulfidic, respectively, implying that the surface decomposition products are bound to metal sites. The H2 is evolved in two features during thermal desorption spectroscopy experiments, a low temperature desorption-limited peak and a high temperature reaction-limited peak. The reaction-limited peak is likely due to the decomposition of a surface hydrocarbon species that results from thiophene decomposition. Photoemission results indicate that C–S bond scission occurs by 170 K and possibly as low as 105 K.
Mice lacking 5-lipoxygenase have increased cortical bone thickness.

5-lipoxygenase (5-LO) metabolites have complex effects on bone cells. We have found that the leukotrine LTB4 and the peptido leukotrienes stimulate osteoclast formation in vitro and in vivo, and are likely involved in the generation of active osteoclast-like cells in giant cell tumors of bone. Recent preliminary observation in mice lacking the gene for 5-LO have not as yet demonstrated any effect on osteoclast function, but these mice have increased cortical bone, suggesting that 5-LO is a negative regulator of bone formation. 5-LO metabolites thus have unique effects on bone cell function, and clarifying their role may be important for the understanding of physiological as well as pathological bone remodeling.
Bioprocessing technology for plant cell suspension cultures

Considering various forms of in vitro plant tissue cultures, cell suspension culture is most amenable to large-scale production of natural compounds, owing primarily to its superior culture homogeneity. This fact has already been demonstrated in several largescale applications, including the commercial shikonin process. The scope of this work is to review the state of the art in bioprocessing technologies pertinent to the secondary metabolite production from suspension cultures of callus cells. In the first part of the review, plant cell physiology relevant to bioprocess design is considered. This is followed by an in-depth discussion on the bioreactor design and operation and its effect on plant cell suspension cultures. Finally, recent commercial exploitation and development are summarized. Following the review, related patents and literature are listed.
The ability of the space telescope to detect extra-solar planetary systems

The Space Telescope can play a key role in searching for and investigating the contents of extra-solar planetary systems. For about 90 nearby stars, positional variations due to major planets would be well within the astrometric capability of the Wide-Field/Planetary Camera system. Since the centroids of star images will be determined to within a milliarcsecond down to 22nd magnitude, there will be an abundance of reference stars at very small angular distances from each planetary system candidate, and they will have small enough motions of their own to provide a reference frame of the stability required.
Web-based simulating system for modeling earthquake seismic wavefields on the grid

We have developed the SYNSEIS (SYNthetic SEISmogram) tool within the GEON (GEOscience Network) project to enable efficient computations of synthetic seismic waveforms for research and education. SYNSEIS is built as a distributed system to support the calculation of synthetic seismograms in 2D/3D media. The underlying simulation software is a finite difference code, E3D, developed by LLNL (S. Larsen). This code is embedded within the SYNSEIS environment and used by our SYNSEIS tool to simulate seismic waveforms of either earthquakes or explosions at regional distances (<1000km). The SYNSEIS architecture is based around a Web service model. Especially, the computing Web services seamlessly access Grid computing resources by hiding the complexity of grid technologies. Even though the Grid computing is well-established in many computing communities, its use among domain scientists still is not trivial because of multiple levels of complexities encountered. We have also developed the grid-enabling E3D application code which takes our own dialect XML inputs that include geological models that are accessible through standard Web services. Also, the XML inputs for this application code contain structural geometries, source parameters, seismic velocity, density, attenuation values, number of time steps to compute, and number of stations. In this paper, we emphasize the development of a state-of-the-art web-based scientific computational environment. Our system can be used to promote an efficient and effective modeling environment to help scientists as well as educators in their daily activities and speed up the scientific discovery process.
Identifiability of the misspecified split hazard models

Unlike standard models, a split population hazard model allows the exit probability to be less than one. Although conceptually attractive, split models are prone to identification problems. In the reduced form estimation of the hazard function, the influence of split may not be distinguishable from that of neglected heterogeneity. For illustration, I use Monte Carlo simulations to highlight the problem of interpreting the structural parameters of the split Weibull and the Weibull-gamma models.
The applicability of the Moebius transformation to mechanical and acoustic impedance modifications

The Moebius transformation maps straight lines or circles in one complex domain into straight lines or circles in another complex plane. This paper will demonstrate that the acoustic response will trace a circle in the complex plane for straight line or circular modifications to mechanical or acoustical impedance. This is due to the fact that the equations relating the acoustic response to the modification are in a form consistent with the Moebius transformation. This is demonstrated for series and parallel mechanical and acoustic impedances. The principles presented in this paper for the case of mechanical impedance are in essence equivalent to what has been termed the generalized Vincent circle by other authors. This paper shows that the principle is valid for multiple excitation problems while also showing the applicability of the principle to acoustic impedance. The key qualifications for applying the Moebius transformation to mechanical and acoustic impedances is that the problem should be linear, and the impedance modification should be in one coordinate direction and at one position. The principle is shown to be valuable for understanding the effect of acoustic impedance modifications in waveguides. The principle is illustrated for several examples including a point excited plate, a construction cab, and an acoustic waveguide.
Dynamics of entrainment of erosional debris and sendimentation

Study of the problem of modern sedimentation is, in essence, an analysis of the corpus delicti—the waste products—of soil-erosion. The objectives of such a study are to locate and appraise the effects of erosional waste, to establish the laws that govern the transportation of sediment from its places of origin to its places of deposition, to determine quantitatively the sources of each type of erosional waste causing each type of sedimentation-damage, and lastly, to develop measures designed to minimize the damages, and, where possible, to create benefits from the stream-borne sediment. A few of the recent findings will perhaps best illustrate the relation of sedimentation to the dynamics of erosion in this new land of ours.
Prognostic factors of recurrence in encapsulated Hurthle cell carcinoma of the thyroid gland: a clinicopathologic study of 50 cases.

BACKGROUND Follicular carcinomas of the thyroid gland, including its oncocytic variant (so-called Hurthle cell carcinoma), are subdivided into the indolent encapsulated (“minimally invasive”) and the clinically aggressive widely invasive tumors. There are, however, cases of encapsulated follicular carcinoma that recur and metastasize. Identifying these cases at the time of diagnosis is crucial for prognostic and therapeutic considerations. Because to the authors' knowledge most studies do not focus exclusively on the encapsulated Hurthle cell carcinoma (EHC), the current study attempted to identify predictors of recurrence in EHC. METHODS A tumor was defined as EHC if it was encapsulated, macroscopically well defined with microscopic but no macroscopic evidence of vascular or capsular invasion, and composed of >75% follicular oncocytic cells. Retrospective chart review and microscopic examination identified 50 primary tumors meeting the above criteria at the Memorial Sloan-Kettering Cancer Center between 1967 and 2005. The cases were analyzed for various histologic and clinical parameters. Each parameter was correlated with recurrence-free survival (RFS). RESULTS Seven of 50 (14%) patients developed disease recurrence. All patients who developed recurrence were found to have a high number of foci of vascular invasion (≥ 4). In univariate analysis, ≥ 4 foci of vascular invasion (P 4 cm (P = .049), the presence of mitosis (P = .018), and a solid/trabecular growth pattern (P = .009) were found to be correlated with a decreased RFS. Extensive capsular invasion, gender, and age did not confer a statistically higher recurrence rate. The finding of a solid/trabecular growth and mitosis correlated with the presence of numerous foci (≥ 4) of vascular invasion (P = .01 and P = .005, respectively). CONCLUSIONS A diligent search for vascular invasion is recommended in EHC that display mitosis or a solid/trabecular growth pattern. The presence of ≥ 4 foci of vascular invasion should alert the pathologist and the clinician to a significantly higher risk of recurrence in EHC. Cancer 2006. © 2006 American Cancer Society.
Real-time, in vivo measurement of radiation dose during radioimmunotherapy in mice using a miniature MOSFET dosimeter probe.

This report presents the first real-time measurement of absorbed radiation dose during radioimmunotherapy in mice. Dose rate and total dose at the center of the tumor were measured after administration of {sup 90}Y-labeled antibodies using a miniature metal oxide semiconductor field-effect transistor radiation dosimeter probe which was inserted into the center of the tumor volume. Continuous real-time measurements were made for as long as 23 h after injection of the radiolabeled antibodies. Comparison of the real-time dose-rate measurements with estimates based on the MIRD formalism indicates good agreement. The real-time measurements are further compared to measurements made in a second experiment in which groups of mice were sacrificed at individual times after injection of the same radiolabeled antibodies. The real-time measurements agree well with the measurements in excised tumors. The real-time measurements have greater time resolution and are much more efficient than traditional uptake measurements. 17 refs., 2 figs.
Sidebands of the Infrared U Center in KBr

The sideband spectrum of KBr: KH has been measured in the infrared at 12\ifmmode^\circ\else\textdegree\fi{}K. The main feature is a strong maximum at 44.5 ${\mathrm{cm}}^{\ensuremath{-}1}$ above the local mode, followed by a weaker but sharper maximum at 80 ${\mathrm{cm}}^{\ensuremath{-}1}$, with additional still weaker structure in the optical-phonon region. The [100] edge-of-zone singular points do not appear in the observed spectrum. A model of the $U$ center is presented in which the ${\mathrm{H}}^{\ensuremath{-}}$ ion vibrating along the $x$ axis is anharmonically coupled to a configurational coordinate $X$ made up of the symmetrical displacements in the $x$ direction of its two nearest-neighbor positive ions at (100) and ($\overline{1}00$). The sideband spectrum is proportional to $\frac{{\ensuremath{\rho}}_{x}(\ensuremath{\omega})}{{\ensuremath{\omega}}^{3}}$, where ${\ensuremath{\rho}}_{x}(\ensuremath{\omega})$ is the power spectrum or projected density of states for this motion of the neighbors. The shell model based on Chalk River neutron data is used. With unperturbed phonons, poor agreement with experiment is obtained for $\frac{{\ensuremath{\rho}}_{x}}{{\ensuremath{\omega}}^{3}}$. Perturbed phonons are treated by a Green's-function technique, and the sideband line shape is calculated as a function of the fractional decrease in central force constant between the ${\mathrm{H}}^{\ensuremath{-}}$ ion and its nearest neighbors. The value of this quantity obtained from the observed local-mode frequency is 0.43. This choice gives a very good fit between the calculated sideband shape and the observed spectrum for KBr: H. The calculated curve has a strong peak at 43.5 ${\mathrm{cm}}^{\ensuremath{-}1}$ which can be interpreted as an incipient resonance in the ${E}_{g}$ (${{\ensuremath{\Gamma}}_{3}}^{+}$) irreducible component of the configuration $X$.
Design of reduced-order state estimators for linear time-varying multivariable systems

The design of reduced-order state estimators for linear time-varying multivariable systems is considered. Employing the concepts of matrix operators and the method of canonical transformations, this paper shows that there exists a reduced-order state estimator for linear time-varying systems that are 'lexicography-fixedly observable'. In addition, the eigenvalues of the estimator can be arbitrarily assigned. A simple algorithm is proposed for the design of the state estimator.
Allopurinol kinetics and bioavailability. Intravenous, oral and rectal administration.

Six normal, healthy adult males received a single dose of allopurinol intravenously, orally in the form of a commercial tablet, and rectally in the form of an extemperaneously prepared suppository (either in a cocoa butter or in polyethylene glycol base). Plasma allopurinol and oxipurinol concentrations were measured over a period of at least 60 h. The following mean (+/- SD) values were obtained from the intravenous allopurinol experiment: clearance, 9.62 +/- 3.49 ml . kg-1 . min-1; Vd, 1.61 +/- 0.74 l/kg; t1/2, 1.62 h. Oxipurinol had a mean t1/2 of 16.90 h. The absolute systemic bioavailability of the oral tablet was 67% +/- 23%, while the allopurinol rectal suppositories produced no measurable plasma concentrations of allopurinol or oxipurinol in any of the subjects. Current use of rectal dosage forms as an adjunct in cancer chemotherapy should therefore be re-examined.
A clinical evaluation of the arcon concept of articulation

Abstract An error in a face-bow transfer to instruments of single-shaft axis design is produced by any selected axis which is located facially by two points or by an adjustable axis face-bow. An instrument is capable only of plane motion in a simple opening and closing motion, and this motion may not occur with the mandible in a similar movement. However, it is not advocated that a face-bow transfer should not be used since it may minimize the error which would be produced without its use. The error involved is further incorporated in the articulation when only a protrusive record is employed to set the equivalent condylar guides of an instrument. No definite superiority could be noted in the clinical evaluation of complete dentures constructed on the arcon over the condylar type of instruments, both of which incorporate a number of averages in design. However, since fewer factors do influence the setting of the arcon guides, 1 the use of multiple maxillomandibular records, such as lateral and protrusive positional records, should be an added advantage to transfer terminal positions to an instrument of arcon design if it is capable of accepting such records.
Growing Up Punk: Negotiating Aging Identity in a Local Music Scene

Punk music, in its thirty-odd-year history, is traditionally conceived of as a youth subcultural phenomenon. As one of many ways to rebel, kids might choose or find in punk rock an anti-authoritarian, destructive, or anarchistic ideology that helps them manage the tumult of adolescence. But what happens next? In this conceptual article, the author is interested in how punks negotiate their identity as punks, as they age. She examines this by looking at people's experiences in a local punk scene. Based on these observations, she argues that “aging identity” and “the scene” are theoretical tools in a dialectic relationship with one another, which highlights the fluidity of both. This theory helps promote “the scene” as a more useful concept than subculture. Furthermore, looking at the local punk rock music scene as a scene—rather than a subculture—illustrates how identity forms over time as a cumulative process, synthesized in the relationship between changing self and other. From her research on a punk scene, the author argues that to construct a long-term conception of scene involvement, punk scene members look to real and idealized others to demonstrate what they see as successful and unsuccessful ways of aging in connection with the music scene.
When People's Judgments of Learning (JOLs) are Extremely Accurate at Predicting Subsequent Recall: The “Delayed-JOL Effect”

Judgments of learning (JOLs), which pertain to knowing what one knows and which help to guide self-paced study during acquisition, have almost never been very accurate at predicting subsequent recall. We recently discovered a situation in which the JOLs can be made to be extremely accurate. Here we report the conditions under which such high accuracy occurs, namely, when the JOL made on the stimulus cue is delayed until shortly after study rather than being made immediately after study. Discussion is focused both on theoretical explanations (to be explored in future research) and on potential applications of the delayed-JOL effect.
A slicer for polyacrylamide gels of 3-, 6-, and 18-mm diameter

Abstract A new gel sectioning device for polyacrylamide gel electrophoresis (PAGE) utilizing an iris diaphragm type of concentric cutting blade has been recently described (1). Although gel cylinders of 5- or 6-mm diam are most often used, cylinders of other diameters are often utilized for purposes of sample economy or ease of preparation. The versatile single cutting device described here enables sectioning of PAGE cylinders having 3-, 6-, or 18-mm diam; it can be easily adapted to accept gels with diameters less than 18 mm.
The quotient semigroup of a semigroup that is a semilattice of groups

Let Q(S) denote the maximal right quotient semigroup of the semigroup S as defined in [4]. In this paper, we initiate a study of Q(S) when S is a semilattice of groups. A structure theorem for such semigroups is given by Theorem 4.11 of [2].
Whose History? Whose Voice? Myth and Resistance in the Rise of the New Left in Mexico

On July 16, 1988, a large opposition political rally materialized on the central plaza of Uruapan, Michoacan-QCardenas country. The date is one week after the national elections for president, which saw the candidate for the ruling Institutional Revolutionary Party (PRI), Carlos Salinas de Gortari, win with the slimmest margin of votes ever officially recorded in its 60 years of unbroken power. Similar antigovernment, pro-Cardenas rallies were being staged simultaneously throughout the Republic. A quick scan of the crowd showed it to be composed primarily of campesinos (peasant farmers) and obreros (lower-class workers). The middle and upper class of Uruapan watched from nearby sidewalk cafes and seemed generally uninterested. Periodically, throughout the afternoon, new groups from surrounding villages would enter the plaza amid a cacophony of band music and shouts announcing their arrival. The first speaker was a white-haired campesino who appeared to be in his seventies. With a firm voice, he extolled to the crowd the virtues of Lazaro Cardenas, Mexico's first populist president after the Revolution of 191017 (serving from 1934 to 1940). He listed a series of accomplishments that the elder Cardenas had brought to the poor people of Michoacan. His son Cuauhtemoc, the "true" winner of the 1988 elections, he went on to say, would bring further advancement to the cause of the poor and disenfranchised. Cuauhtemoc would continue with the program started by his father-a national symbol of the Revolution, a defender of the pueblo (i.e., the Mexican masses). Political rallies have the potential to harness tremendous force, and the emotional involvement of the participants at these political rites is central to its power. A row of stoic old men in dirty, sweat-stained straw hats listened to each speaker's appeal. They began to lift their arms into the air, fists clenched, chanting along with the crowd, "Cuauh-te-moc, Cuauh-te-moc." As an observer, I was struck by the event's power and focused energy. As a participant, I was overwhelmed by its emotional charge.
Ground Clutter In Optical Seekers

A new approach to the study of ground clutter radiation in electro-optical missile seekers has been developed that utilizes a comparison between seeker responses for artificial and measured infrared (IR) scenes. Seeker responses were statistically very much the same for both types of input except at a few isolated points thought to be the commonly measured false targets. The result is that it seems false targets and general random fluctuations caused by background features can be treated separately.
A new type of powder maser

A new type of maser amplifier is described which uses a nonoriented powder as the active material. Because the material is nonoriented, broad absorption bands are present when a magnetic field is applied, rather than narrow absorption lines as in single-crystal material. The broad bands increase the probability that wide bandwidth masers can be developed at reduced cost.
Theory of interphase and antiphase boundaries in f.c.c. alloys

Abstract Equilibrium antiphase domain (APB) and interphase (IPB) boundaries in the CuAu system are examined theoretically using the cluster variation method with multiatom interactions whose magnitudes were previously obtained from a fit of the phase diagram. The IPB energy between equilibrium disordered f.c.c. and ordered Cu3Au phases is strongly temperature (and hence composition) dependent, being much higher for the copper-rich side of the congruent point Tc and having a maximum on that side at about 0.95 Tc. The IPB energies are only slightly anisotropic. The APB energies at constant chemical potential decrease monotonically with increasing temperature: at constant non-stoichiometric composition they increase at low temperature to a maximum well below the disordering temperature. Near the congruent point, the APB undergoes one or more second-order surface phase transitions in which an interfacial layer resembling the inhomogeneous CuAu (L10) phase develops within the boundary. The APB with (hk0) orientation (in our notation) should be perfectly wet by the disordered phase at the disordering temperature for that particular composition.
Cyclic AMP mediates the effects of adrenaline on cardiac purkinje fibres.

MANY of the biochemical actions of catecholamines and other hormones are mediated by alterations in intracellular levels of adenosine 3′,5′-monophosphate (cyclic AMP)1. For example, adrenaline stimulates glycogenolysis in heart muscle by increasing intracellular cyclic AMP levels. It is not clear, however, whether any of the effects of adrenaline on the electrophysiology of the heart are similarly mediated by this cyclic nucleotide2, although recent experiments indicate that exogenous cyclic AMP can accelerate the rhythmic beating of heart cells in culture3. We have studied the currents which underlie the action potential plateau in cardiac Purkinje fibres4–6 as a means of exploring the possible role of the cyclic nucleotide in modifying individual ionic current components. Our results strongly suggest that cyclic AMP does mediate the action of adrenaline on the plateau.
Integrated spectral and image analysis of hyperspectral scattering data for prediction of apple fruit firmness and soluble solids content

Spectral scattering is useful for assessing the firmness and soluble solids content (SSC) of apples. In previous research, mean reflectance extracted from the hyperspectral scattering profiles was used for this purpose since the method is simple and fast, and also gives relatively good predictions. The objective of this study was to improve firmness and SSC prediction for ‘Golden Delicious’ (GD), ‘Jonagold’ (JG), and ‘Delicious’ (RD) apples by integration of critical spectral and image features extracted from the hyperspectral scattering images over the wavelength region of 500–1000 nm, using spectral scattering profile and image analysis techniques. Scattering profile analysis was based on mean reflectance method and discrete and continuous wavelet transform decomposition, while image analysis included textural features based on first order statistics, Fourier analysis, co-occurrence matrix and variogram analysis, as well as multi-resolution image features obtained from discrete and continuous wavelet analysis. A total of 294 parameters were extracted by these methods from each apple, which were then selected and combined for predicting fruit firmness and SSC using partial least squares (PLS) method. Prediction models integrating spectral scattering and image characteristics significantly improved firmness and SSC prediction results compared with the mean reflectance method when used alone. The standard errors of prediction (SEP) for GD, JG, and RD apples were reduced by 6.6, 16.1, 13.7% for firmness (Rpred-values of 0.87, 0.95, and 0.84 and the SEPs of 5.9, 7.1, and 8.7 N), and by 11.2, 2.8, and 3.0% for SSC (Rpred-values of 0.88, 0.78, and 0.66 and the SEPs of 0.7, 0.7, and 0.9%), respectively. Hence, integration of spectral and image analysis methods provides an effective means for improving hyperspectral scattering prediction of fruit internal quality.
METMYOGLOBIN OXIDATION DURING ELECTRON TRANSPORT REACTIONS IN MITOCHONDRIA.

Studies of the intracellular role of myoglobin were carried out by recording spectrophotometric changes in acid metmyoglobin and oxymyoglobin during electron transport reactions with mitochondria prepared from pigeon heart muscle by the method of Chance and Hagihara. The absorption peak of metmyoglobin at 409 mµ disappeared when substrate was added to normal or antimycin-inhibited preparations, and was replaced by a new maximum at 423 to 424 mµ, identified as due to the oxidation to ferrylmyoglobin. Further investigation revealed that the oxidation of metmyoglobin took place with the simultaneous oxidation of reduced flavoprotein. Hydrogen peroxide, formed by the reaction of reduced flavoprotein with oxygen, was considered to be the probable intermediate for the oxidation of metmyoglobin in experiments in which catalase was added as a competitor for the oxidant. When DPNH was added to the reaction mixture, the reductant acted to resynthesize the ferri-derivative by reaction with ferrylmyoglobin. Oxymyoglobin could not be used in place of metmyoglobin in these systems. Under the experimental conditions, oxymyoglobin dissociated when dissolved oxygen was depleted from the medium by enzyme oxidations; the resultant ferromyoglobin underwent oxidation to metmyoglobin.
Mathematical analysis demonstrates that interferons-β and -γ interact in a multiplicative manner to disrupt herpes simplex virus replication

Abstract Several studies suggest that the innate interferons (IFNs), IFN- α and IFN- β , can act in concert with IFN- γ to synergistically inhibit the replication of cytomegalovirus and herpes simplex virus type 1 (HSV-1). The significance of this observation is not yet agreed upon in large part because the nature and magnitude of the interaction between IFN- α / β and IFN- γ is not well defined. In the current study, we resolve this issue by demonstrating three points. First, the hyperbolic tangent function, tanh (x), can be used to describe the individual effects of IFN- β or IFN- γ on HSV-1 replication over a 320,000-fold range of IFN concentration. Second, pharmacological methods prove that IFN- β and IFN- γ interact in a greater-than-additive manner to inhibit HSV-1 replication. Finally, the potency with which combinations of IFN- β and IFN- γ inhibit HSV-1 replication is accurately predicted by multiplying the individual inhibitory effects of each cytokine. Thus, IFN- β and IFN- γ interact in a multiplicative manner. We infer that a primary antiviral function of IFN- γ lies in its capacity to multiply the potency with which IFN- α / β restricts HSV-1 replication in vivo. This hypothesis has important ramifications for understanding how T lymphocyte-secreted cytokines such as IFN- γ can force herpesviruses into a latent state without destroying the neurons or leukocytes that continue to harbor these viral infections for the lifetime of the host.
The academic physician-investigator : a crisis not to be ignored

The academic physician-investigator faces many challenges. Obtaining funding to support research is the greatest impediment. The National Institutes of Health, the single largest source of grants f...
Simulating the effect of economic and policy incentives on natural gas drilling and gross reserve additions

A supply model of natural gas reserve additions is developed and estimated using data on 18,000 new wells drilled in West Virginia between 1977 and 1987. The model is used to quantify the responsiveness of drilling effort and gross reserve additions to changes in the expected wellhead price, taxes, resource depletion and reserve-life index. All the results of the hypotheses tested are in line with conventional wisdom, and their consistency suggests that the model structure offers a useful approach to modeling resource supply in a mature geologic setting like West Virginia. The model structure is well-suited for regions where drilling activities and outcomes cut across formations of varying depth and is more flexible than aggregate models. The model has the capacity to evaluate the response of activity within individual geologic series to prices, taxes and costs.
Measurement of Portal Blood and Transjugular Intrahepatic Portosystemic Shunt Flow with Use of a Retrograde Thermodilutional Catheter

PURPOSE Direct blood flow measurement in the portal vein (PV) and in transjugular intrahepatic portosystemic shunts (TIPS) holds potential as a means of optimizing shunt creation and predicting outcomes. A retrograde thermodilutional flow measurement catheter was recently designed. The purpose of this study was to validate and optimize the technique of blood flow measurement in the PV with use of this catheter in a swine model of TIPS. MATERIALS AND METHODS Six domestic swine underwent TIPS creation. At day 14, shunts were catheterized for venography and portal blood flow measurement with use of thermodilutional catheters. Simultaneous flow measurements were made with use of the thermodilutional and perivascular methods at the same anatomic location within the PV. To test reproducibility of the flow measurement, repeated measurements were performed in the PV and shunt. RESULTS Fifty-five measurements of PV blood flow with the thermodilutional catheter and perivascular probe were made in five animals. Perivascular probe placement was unsuccessful in one animal. There was high correlation between the thermodilutional and perivascular measurements ( r 2 = 0.96; Q periv · 0.80 = Q therm + 147 mL/min; n = 55; range, 205-1541 mL/min). The difference between two consecutive thermodilutional measurements and their mean was less than 50 mL/min in 72% of measurements and less than 100 mL/min in 94% of measurements ( N = 85 pairs). CONCLUSION Measurement of PV blood flow with use of a retrograde thermodilutional catheter system yields reliable and reproducible results. This catheter system holds promising utility as a device for measuring flow within TIPS and the PV.
Radiofrequency and cryoablation of atrial fibrillation in patients undergoing valvular operations.

Background. Previous studies have shown that the maze operation can restore sinus rhythm and atrial transport function in patients with chronic atrial fibrillation. The purpose of this study was to test the feasibility of the application of radiofrequency and cryoablation as an alternative to the classic maze operation. Methods. Twelve patients undergoing mitral valve procedures were included in this study. Radiofrequency and cryoablation were applied to create lesions in both atria to simulate the classic maze operation. Results. There were two surgical deaths. At the mean follow-up of 10.25 months for the remaining 10 patients; 6 were in sinus rhythm, 2 in atrial rhythm, 1 in paroxysmal atrial tachycardia, and 1 in atrial fibrillation. Doppler echocardiography at 6-month follow-up showed emergence of biatrial transport function in 3 patients and right atrial contractility in 8. At 12-month follow-up of 5 patients, Doppler echocardiography showed biatrial transport function in 3 and right atrial contractility in 4. Conclusions. Our modified maze procedure during valvular operation is effective for achieving an acceptable success rate to restore sinus rhythm and atrial transport function in patients with chronic atrial fibrillation.
On transformation noise as a model for correlated noise

The authors consider transformation noise processes, which are those that can be generated by passing an underlying noise process through a memoryless invertible nonlinearity. They point out the close relationship between the dependency structure of the transformation noise and that of the underlying noise. The use of the class of transformation noise generated from multivariate Gaussian background noise to approximate other noise processes is proposed. This class has tractable, closed-form joint densities. Some ad hoc ways to find the parameters in the model are suggested. It is shown that the nonlinearities in the optimal detector, in the case of transformation noise with a mixture marginal density are approximately the sum of the nominal term and a term proportional to the parameter in . >
Specific Labeling of Lens Aldehyde Dehydrogenase Class 1 from 3H-Cholesterol or Its Derivatives

We investigated the possibility that sterols could covalently modify ocular lens cell proteins. Incubation of cultured bovine lens epithelial cells (BLEC) with 3H-cholesterol led to the lab
Objective assessment of coronary angioplasty for multivessel disease: results of exercise stress testing.

Abstract The efficacy of coronary angioplasty in multivessel coronary artery disease was evaluated in a series of 145 consecutive patients in whom angioplasty had been successful and in whom a follow-up exercise stress test was performed within 2 months. Exercise stress test results of these patients with multivessel disease were compared with those of 177 patients with single vessel disease after successful coronary angioplasty. The postangioplasty exercise test showed ischemia in 13% of patients with single vessel and 29% of those with multivessel disease, although only 7 and 13%, respectively, experienced angina. The mean exercise duration was comparable for patients with multivessel disease (453 ± 174 s) and single vessel disease (476 ± 166 s). To assess the impact of the degree of revascularizalion in patients with multivessel disease on the results of exercise testing, 48 patients with completely revascularized vessels and 97 with incompletely revascularized vessels were evaluated. The mean exercise duration (459 ± 178 versus 450 ± 173 s), mean maximal heart rate (132 ± 31 versus 136 ± 25 beats/min) and mean systolic blood pressure (174 ± 25 versus 170 ± 26 mm Hg) were similar in completely and incompletely revascularized groups. Exercise-induced angina occurred in 13% of both groups. Ischemic ST segments were more common in the incompletely revascularized group (34 versus 19%, p = 0.06). Thus, exercise stress testing provides evidence that successful angioplasty can relieve electrocardiographic manifestations of ischemia as well as anginal symptoms in the majority of patients with either single or multivessel coronary artery disease who are suitable candidates for the procedure. Compared with patients with complete revascularization, those with incomplete revascularization by design are more likely to demonstrate ischemia although functional performance is comparable.
Retinoic acid receptor-α messenger RNA expression is increased and retinoic acid receptor-γ expression is decreased in Barrett's intestinal metaplasia, dysplasia, adenocarcinoma sequence

Abstract Background. Expression levels of the retinoic acid receptors (RAR-α, RAR-β, and RAR-γ) are significantly different in neoplastic tissues compared with non-neoplastic tissues for some tumors. This study investigated whether retinoic acid receptor messenger RNA (mRNA) expression levels are altered in Barrett's esophagus and Barrett's adenocarcinoma tissues. Methods. Relative mRNA expression levels of the RARs were quantified by using the ABI 7700 Sequence Detector (Taqman) system in Barrett's intestinal metaplasia (n = 15), dysplasia (n = 6), adenocarcinoma (n = 17), and matching normal esophagus tissues (n = 36). Results. RAR-α expression was significantly increased, and RAR-γ expression was significantly decreased, at higher stages in the Barrett's sequence. There was almost complete loss of RAR-γ expression (relative expression level ≤ 1) in a majority (70%) of the dysplasia and adenocarcinoma tissues. There were significant differences in RAR-α and RAR-γ expression in histopathologically normal tissues in patients with cancer versus patients without cancer. RAR-β expression levels were significantly elevated in adenocarcinoma versus normal esophagus tissues. The RAR expression profile was similar for cancers arising within the esophagus and for cancers arising at the gastroesophageal junction. Conclusions. RAR mRNA expression levels are significantly different in Barrett's tissues compared with normal esophagus tissues, and these levels are significantly different in Barrett's dysplasia and adenocarcinoma tissues compared with nondysplastic tissues. These results suggest that RAR mRNA levels may be useful biomarkers for this disease and that gastroesophageal junction adenocarcinomas are genetically similar to esophageal adenocarcinomas. These results also suggest that a cancer field is present in the esophagus in patients with cancer and that genetic alterations can precede histopathologic alterations in this disease. (Surgery 2001;129:267-76.)
Angle-insensitive and solar-blind ultraviolet bandpass filter

We present a metal–dielectric stack ultraviolet (UV) bandpass filter that rejects the longer wavelength, visible spectrum and is thin and relatively insensitive to the angle of incidence. Parametric evaluations of the reflection phase shift at the metal–dielectric interface provide insight and design information. This nontrivial phase shift allows coupled Fabry–Perot resonances with subwavelength dielectric film thickness. Furthermore, the total phase shift, with contributions from wave propagation and nontrivial reflection phase shift, is insensitive to the angle of incidence. Filter passbands in the UV can be shifted to visible or longer wavelengths by engineering the dielectric thickness and selecting a metal with an appropriate plasma frequency.
Encouraging clean energy investment in developing countries: what role for aid?

A large portion of foreign assistance for climate change mitigation in developing countries is directed to clean energy facilities. To support international mitigation goals, however, donors must make investments that have effects beyond individual facilities. They must reduce barriers to private-sector investment by generating information for developers, improving relevant infrastructure, or changing policies. We examine whether donor agencies target financing for commercial-scale wind and solar facilities to countries where private investment in clean energy is limited and whether donor investments lead to more private investments. On average, we find no positive evidence for these patterns of targeting and impact. Coupled with model results that show feed-in tariffs increase private investment, we argue that donor agencies should reallocate resources to improve policies that promote private investment in developing countries, rather than finance individual clean energy facilities. Policy relevance We suggest that international negotiations could usefully shift the focus of climate change finance towards adaptation in exchange for mitigation-improving policy reforms in developing countries. There is little evidence that mitigation-related financing is having broader effects on energy production, so new financial arrangements should be the focus of future negotiations. Additionally, international donors should focus efforts on reforming policies to attract private investment.
A biologically inspired networking model for wireless sensor networks

Wireless sensor networks have emerged in strategic applications such as target detection, localization, and tracking, where the large scale renders centralized control prohibitive. In addition, the finite batteries of the nodes demand energy aware network control. In this article we propose an energy-efficient topology management model inspired by biological intercell signaling schemes, which allows sensor nodes to form clusters around imminent targets in a purely distributed and autonomous fashion. In particular, nodes in the target vicinity collaborate to form a cluster according to their relative observation quality values, based on a bioinspired lateral induction process. Subsequently, the clustered nodes compete according to their energy levels until some of them gain active status while the rest remain idle, based on a bio-inspired lateral inhibition process. A final phase of the model has the active cluster members compete until one of them becomes the cluster head, again based on the lateral inhibition process. We examine the behavior of such a network control flow in both finite-size and infinite-size networks. Specifically, we show that the proposed model is inherently stable and discuss its convergence for networks of finite size. Furthermore, we discuss the asymptotic behavior when the number of nodes goes to infinity, where we study the average number of active cluster members.
Modelling of global boundary effects on harmonic motion imaging of soft tissues.

Biomechanical imaging techniques have been developed for soft tissue characterisation and detection of breast tumours. Harmonic motion imaging (HMI) uses a focused ultrasound technology to generate a harmonic radiation force in a localised region inside a soft tissue. The resulting dynamic response is used to map the local distribution of the mechanical properties of the tissue. In this study, a finite element (FE) model is developed to investigate the effect of global boundary conditions on the dynamic response of a soft tissue during HMI. The direct-solution steady-state dynamic analysis procedure is used to compute the harmonic displacement amplitude in FE simulations. The model is parameterised in terms of boundary conditions and viscoelastic properties, and the corresponding raster-scan displacement amplitudes are captured to examine its response. The effect of the model's global dimensions on the harmonic response is also investigated. It is observed that the dynamic response of soft tissue with hig...
Candelabra systems and designs

Abstract Combinatorial structures called candelabra systems can be used in recursive constructions to build Steiner 3-designs. We introduce a new closure operation on natural numbers involving candelabra systems. This new closure operation makes it possible to generalize various constructions for Steiner 3-designs and to create new infinite families of Steiner 2-designs and 3-designs. We provide an independent proof for Wilson's “product theorem” for Steiner 3-designs. We also construct new group divisible designs of strength 2 and 3.
Modeling Neural Spiking Activity in the Sub-Thalamic Nucleus of Parkinson's Patients and Healthy Primates

Abstract How neurons in humans encode information about the outside world and how this processing changes when the brain is diseased are central questions in neuroscience and medicine. Historically, microelectrode recordings of single-unit neuronal activity have been confined to animal preparations. Recently, it has become possible to obtain single-unit recordings in humans undergoing deep brain stimulation surgery. In this study, we recorded neuronal activity from the sub-thalamic nucleus (STN) of the basal ganglia of patients with Parkinson's disease (PD). In parallel, identical experiments were conducted on a healthy primate, providing a rare opportunity to analyze STN neuronal activity recorded in both the disease and healthy state during the same behavioral tasks. We developed point process models of STN neurons to capture neural spiking dynamics as a function of extrinsic stimuli and the neuron's own spiking history. Our models quantify, for the first time, pathological signatures in PD neural activity such as bursting, 10-30Hz oscillations, and loss of directional plurality, which may directly relate to motor disorders observed in PD patients such as bradykinesia, resting tremor, and rigidity.
A neurocytoma and an associated lenticulostriate artery aneurysm presenting with intraventricular hemorrhage: case report.

Objective and importance Hemorrhage associated with central neurocytoma has been described previously, but never in association with an aneurysm originating from a feeding artery. We present the first reported case of a central neurocytoma in a patient with intraventricular hemorrhage caused by rupture of an aneurysm on a lenticulostriate artery that supplied the tumor. Clinical presentation A 35-year-old man who presented with an intraventricular hemorrhage underwent magnetic resonance imaging and cerebral angiography that disclosed a right lateral intraventricular mass and a 7-mm fusiform aneurysm from a lateral lenticulostriate branch of the right middle cerebral artery. Intervention The patient underwent a contralateral transcallosal exploration and resection of the tumor, with excision of the adjacent lenticulostriate artery aneurysm. Pathological review demonstrated that the tumor was a neurocytoma. The aneurysm was discrete from the tumor but occurred on a vessel that supplied the tumor. Conclusion Previous reports have demonstrated that intraventricular neurocytoma may present with tumor hemorrhage. In this case, an aneurysm separate and distinct from the tumor was the bleeding culprit, and the aneurysm was on an artery that fed into the tumor. Any such aneurysm must be identified and treated appropriately for therapy to be complete.