cssi/SciSciGPT-SciSciNet huggingface dataset:
In vivo analysis of voltage-dependent calcium channels.

The molecular cloning of calcium channel subunits has identified an unexpectedly large number of genes and splicing variants, many of which have complex expression patterns: a central problem of calcium channel biology is to understand the functional significance of this genetic complexity. The genetic analysis of voltage-dependent calcium channels (VDCCs) provides an approach to defining channel function that is complimentary to pharmacological, electrophysiological, and other molecular methods. By discovering or creating alleles of VDCC genes, one can gain an understanding of the VDCC function at the whole animal level. Of particular interest are mutations in the α1 genes that encode the pore forming subunits, as they define the specific channel subtypes. In fact, a variety of calcium channelopathies and targeted mutations have been described for these genes in the last 6 years. The mutant alleles described below illustrate how phenotype analysis of these alleles has uncovered very specific functional roles that can be localized to specific synapses or cells.
Stratton–Chu vectorial diffraction of electromagnetic fields by apertures with application to small-Fresnel-number systems

The Stratton–Chu theory of electromagnetic (EM) scattering is used to develop a Kirchhoff formalism of the diffraction of EM waves by an aperture. The theory is applied to the study of the diffraction of a polarized EM wave by small-Fresnel-number systems. It is demonstrated through sample numerical calculations that the vectorial aspects of the EM waves are important, especially for fields in the microwave regime. The focal shift is then calculated with the vectorial aspects taken into account.
Tunneling of holes from acceptor levels in an applied field

Abstract A formula is derived for the rate of tunneling of holes from bound acceptor levels into valence band states in the presence of an applied field. The rate of this quantum mechanical field ionization process is very strongly dependent on the strength of the applied field. The derivation of the rate formula goes beyond previous treatments by taking into account details of the band structure of common semiconductors near valence band maxima, including the degeneracy of light and heavy hole bands at the band maxima. Field-induced interband transitions are also taken into account.
Parameters estimation using sliding mode observer with shift operator

Abstract In different areas of engineering, mathematical models are used to describe real life phenomena and experiments are conducted to validate them. It is common that these models may contain a number of parameters that cannot be measured directly or calculated. Thus, parameter estimation is an important step in the process of modeling based on empirical data of the system. In the control system’s literature, one can find considerable amount of research in the area of system parameters identification. Most of these techniques are based on minimizing the estimation error in some statistical framework such as least square error based methods. In most cases, using these techniques, one can prove the uniform exponential stability of the state and parameter estimation error, but the convergence rate can be too low. However, when designing control systems, knowledge of unknown immeasurable (or even time varying) parameters might be crucial for the operation of the controller and thus have to be accurately estimated with a desired rate of convergence. In this paper, we demonstrate a way to provide an estimation technique with tunable convergence rate using sliding mode with linear operators such as time delay.
Vapor-liquid equilibrium predictions of refrigerant mixtures from a cubic equation of state with a Ge-EoS mixing rule

Abstract A modified excess Gibbs energy model which is based on the local composition concept and assigns a single energy parameter per pair of components, is incorporated into the G E —EoS thermodynamic formalism for vapor-liquid equilibrium (VLE) calculations of simple and complex refrigerant mixtures. One temperature set of data close to 273 K is used to obtain the model's parameters, which are used to extrapolate the VLE at other temperatures and pressures. A one-parameter form of the model based on the Wong-Sandler mixing rule is presented for several simple systems. The physical significance of the model's energy parameter is connected to the preference of the mixture for like to unlike interactions. The model is applied for VLE predictions of the ternary system R14-R23-R13, and the results are compared to calculations using the 3PWS model [H. Orbey. S.I. Sandler, Ind. Eng. Chem. Res. 34 (1995) 2520–2525] and the van der Waals mixing rule. Modelling of a few complex systems with only three data points given at each temperature is shown with a two parameter version of our model on the basis of the Huron-Vidal mixing rule.
Racial/ethnic differences in poststroke rehabilitation utilization in the USA.

Longstanding racial/ethnic disparities exist in the USA in the areas of healthcare access, healthcare utilization and health-related outcomes of chronic health conditions, such as stroke. Regarding stroke specifically, significant racial/ethnic disparities in stroke incidence, severity and outcomes have been reported. Despite these differences, little attention has been given to potential racial/ethnic differences in the utilization of rehabilitation services for patients after stroke. To date, only a few studies have been specifically designed to examine racial/ethnic differences in rehabilitation service utilization. A review of these studies and related studies suggests that racial/ethnic differences may be present in the utilization of poststroke rehabilitation services. Consequently, new studies are needed to delineate how race/ethnicity influences utilization of poststroke rehabilitation services and to determine how a reduction in this disparity gap could improve stroke-related outcomes among racia...
The dissociation and separation of bovine adenohypophysial cells

Bovine adenohypophysial tissue was dissociated by sequential enzymatic incubation in a continuous flow system. Dispersed cells separated into discrete fractions after centrifugation in isopycnic bovine serum albumin gradients. The dispersed and separated cells were prepared for microscopic identification and differential counts by centrifugal cytology. Radioimmunoassays for LH, FSH, TSH, and Prl were used to corroborate the differential counts and determine the homogeneity of the fractions. The thyrotrophs banded at an average density (\(\bar \rho \)) of 1.0417, the FSH-secretory cells at\(\bar \rho = 1.0597\), the LH-secretory cells at\(\bar \rho = 1.0458\), and the Prl-secretory cells at\(\bar \rho = 1.0126\). A 7–16 fold enrichment of different cell populations was possible. In bovine hypophyses each hormone appears to be formed by specific cells: the average TSH concentrations of the thyrotrophs were 5.1 pg/cell and the average LH and FSH concentrations were 4.7 and 4.9 pg/cell for LH-and FSH-secreting cells, respectively. The average Prl concentration was 4.9 pg/cell for Prl-secreting cells.
Simulation of the growth of a binary composite by a controlled thermal annealing

The Metropolis algorithm is used to study the evolution of the density profile of particle species in a model binary composite material on a simple cubic lattice. A specified fraction of the lattice sites are occupied by particles of type A and the remaining sites are occupied by particles of type B. The Hamiltonian for the system includes both nearest-neighbor particle-particle interactions and the interaction of the particle with a gravitational field. Particle-particle interaction strength, gravity, and the temperature govern the hopping of each particle in our annealing process. Variation of the planar density of the system by particle type is studied as a function of annealing time, temperature, and the volume fraction of the two components
Surface topography of the 30 s Escherichia coli ribosomal subunit: reactivity towards fluorescein isothiocyanate.

Abstract Celite-adsorbed fluoreseein isothiocyanate has been reacted with 30 s and 70 s ribosomes. At pH 9.0, approximately 12 dyes are found attached to the 30 s ribosomes and 11 to the 70 s ribosomes. When the subunits of the latter are separated, only 3 dyes are found attached to the 30 s particle. In all cases, virtually full biological activity is maintained. The detailed pattern of protein reactivity has been assessed by two-dimensional acrylamide gel electrophoresis. Most of the proteins of the isolated 30 s particle are reactive towards fluoreseein isothiocyanate. In contrast, many of these are protected when the reactivity of the 30 s moiety of the 70 s particle is examined. From the detailed results, a number of tentative conclusions about ribosome topography can be drawn. For example, proteins P1, P3, P4a and P15 appear to be definitely exposed in both 30 s and 70 s particles. P4b is almost certainly buried in both. P4, P8, P10, P10a, P11 and P13 are strongly shielded by the 50 s particle. One 30 s protein, P15, is much more strongly labeled in the 70 s particle than in the free 30 s. This indicates that the 30 s particle undergoes a conformational change when it combines with the 50 s particle.
Secondary hydroeruptions in pyroclastic-flow deposits: Examples from Mount St. Helens

Abstract Secondary hydroeruptions occur in pyroclastic-flow deposits when water or ice is trapped beneath hot pyroclastic debris and rapidly heated to steam. These eruptions display various styles of activity including fumarolic degassing, tephra fountaining, and explosive cratering. The deposits, which occupy the layer 3 stratigraphic position on the top of pyroclastic-flow units, can be distinguished from ash-cloud material by lateral thickness variation, clast composition, and other sedimentary features. The ejecta of secondary hydroeruptions comprise a subset of hydrovolcanic pyroclastic deposits. A small secondary hydroeruption observed on the Mount St. Helens pumice plain in 1981 produced tephra that was emplaced ballistically, by deposition from base surges, and by fallout from an eruption column. Stratigraphic descriptions and grain-size analysis of the ejecta from several secondary craters on the pumice plain demonstrate that the bedforms produced by a hydroeruption change with crater diameter. In particular, craters of small diameter are surrounded by interbedded ripple-laminated ash horizons and nonstratified, fines-depleted units; large craters have ejecta ramparts comprised of coarse dunes and antidunes. These bedform changes are related to a progressive increase in eruptive energy, which produces base surges of greater power and eruptive columns of greater height. We suggest that the style of activity displayed during a secondary hydroeruption is controlled by both the total thermal energy of the system and the permeability of the pyroclastic overburden.
Absolute radiometric calibration of digital imaging systems

We have developed a tunable laser-based facility for the absolute radiometric calibration of digital imaging system such as CCD cameras, spectrographs, and microscopes. Several types of silicon-based digital imaging systems have been calibrated in this new facility, including a commercially available camera equipped with a removable photopic filter, a custom-designed digital microscope, and a CCD spectrography. We present result of the CCD camera calibration in detail and discuss relevant aspects of the microscope and spectrograph calibrations. During the radiometric calibration, the pixel-to-pixel uniformity, linearity, and absolute spectral responsivity of each system were determined over the visible spectral range. Each of these aspects of the CCD camera calibration will be presented, along with a discussion of the measurement uncertainties.
Epidemiology and outcomes associated with anemia during long-term support with continuous-flow left ventricular assist devices.

Abstract Background The purpose of this study was to define the prevalence and clinical ramifications of anemia in patients implanted with a continuous-flow left ventricular assist device (CF-LVAD). Methods and Results Patients implanted with a CF-LVAD from January 1, 2008, to April 30, 2012, were included in this retrospective cohort study. The primary outcome was the prevalence of anemia throughout the 1st year of device support. Secondary end points included the impact of anemia on rates of readmission to hospital and mortality. Ninety-one patients were included; the prevalence of anemia 360 days after implantation was significantly reduced compared with baseline (61.4% vs 79.1%, respectively; P = .032); 65.4% of anemic patients and 34.6% of nonanemic patients were readmitted at least once ( P = .067). The median number of readmissions in the anemic compared with the nonanemic group was 4 (interquartile range [IQR] 2-6) versus 1.5 (IQR 1-3), respectively ( P 3 readmissions during the 1st year, 19 were anemic compared with 1 patient who was not anemic ( P Conclusions Anemia remains a prevalent condition while on CF-LVAD support and is associated with a significant increase in the number of hospital readmissions.
Scheduling material handling vehicles in a container terminal

Increasing global trade has created the need for efficient container ports. The goal of the port is to move containers as quickly as possible and at the least possible cost. Goods that are delayed at the port are inevitably tardy when delivered to the customer, and thus sanctioned by late charges. Two key activities in the port are (i) unloading of containers from truck and then storage in the export area, and (ii) removal of containers from import storage and then loading onto the trucks. Since containers are large and heavy, specialized material handling vehicles are required for transporting them within the terminal. The focus of this paper is on port terminals where straddle carriers are primarily used to move containers. Container terminals typically have well developed computer and communication networks. Through these networks a terminal scheduler will control and schedule the movement of the straddle carrier fleet in real time. The objective of the terminal scheduler is to minimize the empty trave...
Prevention of adrenal cortical hypertrophy in diabetic rats by the use of insulin.

SEVERAL recent papers (Bennett and Koneff, 1946; Applegarth, 1949; Eranko, 1951) have reported enlargement and increased function of the adrenal cortex of rats made diabetic with alloxan. Bennett and Koneff (1946) felt this hypertrophy was probably due to the altered metabolism of the diabetic animal rather than the direct toxic effect of alloxan. Eranko (1951), however, suggested the changes might reflect the increased secretion of insulin following the injection of alloxan. This observation of increased adrenal cortical function is contrary to the findings of Field and Marble (1951) who noted diminished adrenal cortical activity in some diabetics. This apparent contradiction might depend on whether an attempt is made to regulate the diabetes with insulin and thereby reduce the stress of an uncontrolled metabolic statec. The present study was undertaken to determine whether insulin would prevent the adrenal cortical hyperactivity of diabetic rats using histochemical appearances as well as adrenal weights...
Monoamine Oxidase Inhibition by Ethanol in vitro

HYPNOTIC doses of ethanol have been reported by Rosenfeld1 to prolong the metabolic inactivation of exogenous serotonin (5-hydroxytryptamine) in mice. Olson, Gursey, and Vester2 found the urinary excretion of 5-hydroxyindolylacetic acid (5–HIAA) to be significantly below normal in alcoholics, even after 6 months of abstinence on rigidly controlled diets. These findings suggest that ethanol may act as a monoamine oxidase (MAO) inhibitor. On the other hand, Gursey and Olson3 have reported depression of brain-stem serotonin and norepinephrine in rabbits after both acute and chronic ethanol administration; suggesting that ethanol may act to release stores of bound amines. Pscheidt, Issekutz, and Himwich4 were unable to confirm this finding. In our laboratories, we have found that a single dose of ethanol, given orally to human volunteers, produces a marked, but transitory, increase in the urinary excretion of tryptamine5.
Relationship between genetic variation in thermal stability and electrophoretic mobility of mouse beta-galactosidase.

We have examined the relationships between the genetic determinants for mouse β-galactosidase heat stability and electrophoretic mobility, in order to clarify previous reports indicating that a variation for enzyme heat stability is restricted to kidney while that for electrophoretic mobility is expressed in all tissues. We find that the two phenotypes show concordant strain distributions and cosegregate in genetic crosses. In contrast to a previous report, the thermal stability variation is expressed in all tissues, although the absolute rate of enzyme inactivation is tissue specific. The evidence supports the notion that a single β-galactosidase structural locus is expressed in all tissues and that the differences in enzyme stability between tissues results from posttranslational enzyme modification.
Signal-known exactly detection performance in tomosynthesis: does volume visualization help human observers?

Tomosynthesis produces three-dimensional images of an object, with non-isotropic resolution. Tomosynthesis images are typically read by human observers in a stack viewing mode, displaying planes through the tomosynthesis volume. The purpose of this study was to investigate whether human performance in a signal-known exactly (SKE) detection task improves when the entire tomosynthesis volume is available to the observer, compared to displaying a single plane through the signal center. The goal of this study was to improve understanding of human performance in order to aid development of observer models for tomosynthesis. Human performance was measured using sequential 2-alternative forced choice experiments. In each trial, the observer was first asked to select the signal-present ROI based on a single 2D tomosynthesis plane. Then, scrolling was enabled and the observer was able to select the signal-present ROI, based on knowledge of the entire volume. The number of correct decisions for 2D and 3D viewing was recorded, and the number of trials was recorded for which a score increase or decrease occured between 2D and 3D readings. Test images consisted of tomosynthesis reconstructions of simulated breast tissue, where breast tissue was modeled as binarized power-law noise. Tomosynthesis reconstructions of designer nodules of r = 250μm, r = 1mm, r = 4mm were added to the structured backgrounds. For each signal size, observers scored 256 trials with signal amplitude set so that the proportion of correct answers in the single slice was 90%. For two observers, a slight increase in performance was found when adjacent tomosynthesis slices were displayed, for the two larger signals. Statistical significance could not be established. The number of decision changes was analyzed for each observer. For these two observers, the number of decision changes that led to a score increase or decrease were outside the 95% confidence interval of the decision change being random, indicating that for these two observers, displaying the tomosynthesis stack did boost performance. For the other two observers, decision changes that increased or decreased the score were within the 95% confidence interval of guessing, indicating that the decision changes were due to a satisfaction of search effect. However the results also indicate that the performance increase is small and the majority of information appears to be contained in the tomosynthesis slice that corresponds to the center of the lesions.
Mouse NK cell-mediated rejection of bone marrow allografts exhibits patterns consistent with Ly49 subset licensing.

Natural killer (NK) cells can mediate the rejection of bone marrow allografts and exist as subsets based on expression of inhibitory/activating receptors that can bind MHC. In vitro data have shown that NK subsets bearing Ly49 receptors for self-MHC class I have intrinsically higher effector function, supporting the hypothesis that NK cells undergo a host MHC-dependent functional education. These subsets also play a role in bone marrow cell (BMC) allograft rejection. Thus far, little in vivo evidence for this preferential licensing across mouse strains with different MHC haplotypes has been shown. We assessed the intrinsic response potential of the different Ly49+ subsets in BMC rejection by using β2-microglobulin deficient (β2m−/−) mice as donors. Using congenic and allogeneic mice as recipients and depleting the different Ly49 subsets, we found that NK subsets bearing Ly49s, which bind “self-MHC” were found to be the dominant subset responsible for β2m−/− BMC rejection. This provides in vivo evidence for host MHC class I–dependent functional education. Interestingly, all H2d strain mice regardless of background were able to resist significantly greater amounts of β2m−/−, but not wild-type BMC than H2b mice, providing evidence that the rheostat hypothesis regarding Ly49 affinities for MHC and NK-cell function impacts BMC rejection capability.
Unique synergism or antagonism of combinations of chemotherapeutic and hormonal agents in human prostate cancer cell lines

Objective To evaluate combinations of anti-tumour agents in tissue cultures using three established cell lines derived from patients with prostate cancer to obtain potential candidates for therapeutic testing in patients with prostate cancer. Materials and methods Seventeen anti-tumour agents were tested for synergism or antagonism in combination studies in DU 145, PC 3 and LnCaP cell lines. After determining the dose required for 50% inhibition of growth in each, combinations were screened using the median-effect plot and combination-index isobolograms. Results Estramustine (the primary product of dephosphorylation of estramustine phosphate) showed strong synergism in all three cell lines with hydroxyflutamide, the non-immunosuppressive cyclosporin analogue PSC 833, and Liarozole . In the hormone-sensitive cell line LnCaP alone, synergism was also observed with vinblastine, paclitaxel, docetaxel, bicalutamide, ketoconazole and all-trans-retinoic acid. Other synergistic combinations of two agents were: Liarozole plus docetaxel in LnCaP, PSC 833 plus bicalutamide in DU 145 and PC 3, dexamethasone plus docetaxel in LnCaP, and finasteride plus hydroxyflutamide. Synergistic combinations of three agents were: estramustine plus PSC 833 and Liarozole and schedule-dependent combinations of estramustine, PSC 833, and all-trans-retinoic acid. Conclusion Some of the synergistic combinations have shown clinical effects in patients with hormone-refractory prostate cancer. Based on these findings, new combinations, e.g. estramustine with either PSC 833 or Liarozole, need to be clinically evaluated.
MODELS FOR OPTIMAL LEAD TIME REDUCTION

Most inventory and production planning models in the academic literature treat lead times either as constants or random variables with known distributions outside of management control. However, a number of recent articles in the popular press have argued that reducing lead times is a dominant issue in manufacturing strategy. The benefits of reducing customer lead times that are frequently cited include increased customer demand, improved quality, reduced unit cost, lower carrying cost, shorter forecast horizon, less safety stock inventory, and better market position. Although the costs of reducing lead times in the long term may be relatively insignificant compared with the benefits, in the short term these costs can have a significant impact on the profitability of a firm. This article develops a conceptual framework within which the costs and benefits of lead time reduction can be compared. Mathematical models for optimal lead time reduction are developed within this framework. The solutions to these models provide methods for calculating optimal lead times, which can be applied in practice. Sensitivity analysis of the optimal solutions provides insight into the structure of these solutions.
Interfaces for emergent semantics in multimedia databases

In this paper, we introduce our approach to multimedia database interfaces. Although we deal mainly with image databases, most of the ideas we present can be generalized to other types of data. We argue that, when dealing with complex data, such as images, the problem of access must be redefined along different lines than text databases. In multimedia databases, the semantics of the data is imprecise, and depends in part on the user's interpretation. This observation made us consider the development of interfaces in which the user explores the database rather than querying it. In this paper, we give a brief justification of our position and present the exploratory interface, which we have developed for our image database El Nino.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Detection of Infectious Hematopoietic Necrosis (IHN) Virus in Rearing Units for Steelhead before and during IHN Epizootics

Abstract Nursery tanks and Burrows ponds at Dworshak National Fish Hatchery, Ahsahka, Idaho, containing age-0 steelhead Oncorhynchus mykiss were sampled for IHN virus before and during epizootics of IHN. The hatchery water supply was also sampled weekly from March to September. By use of a precipitation method involving polyethylene glycol (PEG) to concentrate virus from water samples, IHN virus was detected in nursery tanks and Burrows ponds during the early stages of epizootics at concentrations ranging from 0.1 to 0.3 plaque-forming units (pfu)/mL. Peak virus concentrations were 1–5 pfu/mL in nursery tanks and exceeded 50 pfu/mL in Burrows ponds. When tangential flow filtration was used in conjunction with PEG precipitation, virus was detected in Burrows ponds at concentrations of 0.007–0.07 pfu/mL, 3–12 d before periods of rapidly increasing mortality. The results indicate that IHN epizootics begin with waterborne IHN virus at relatively low concentrations. Virus was not detected in the hatchery water...
Estimation of multipath channel response in frequency selective channels

A novel discrete-time method is proposed for estimating the impulse response of a frequency-selective digitally modulated communication channel. The received signal is first demodulated and sampled and then the fourth-order cumulants of the resulting discrete-time sequence are estimated. The method estimates the channel impulse response from the complex cepstrum of the aforementioned fourth-order cumulants (i.e. tricepstrum). The method depends only on the second- and fourth-order statistics of the transmitted sequence and is capable of reconstructing nonminimum-phase impulse responses. Monte Carlo simulation results demonstrate the effectiveness of the method, its low sensitivity to observation noise, and its improved performance in terms of probability of error or the reconstructed transmitted sequence. >
Theory of constraints at UniCo: analysing The Goal as a fictional case study

As a fictional case study, Eliyahu Goldratt's novel about manufacturing, The Goal: A Process of Ongoing Improvement, presents a constraint-focused approach to production management. As a novel, the book does not emphasise the quantitative details of the plant improvements. However, a great amount of information about the plant is spread throughout the book. By collecting and analysing this data, a concrete picture of the plant's capacity and its improvements may be developed, which can greatly help the book's readers understand and evaluate the cumulative impact from the plant's ‘process of ongoing improvement’.
Isotopic diffusion in polycrystalline ice

Quantitative ice-core paleoclimatology must account for post-depositional processes, such as vapor-phase diffusion in the firn. After pore close-off, diffusion continues to smooth the stable-isotope records δ 18O and δD that are eventually recovered from the ice, leading to the loss of high-frequency information. Johnsen and others (1997) found much higher rates of diffusive smoothing in the Greenland Icecore Project (GRIP) Holocene ice than would be predicted by diffusion through solid ice alone, and Nye (1998) argued that transport through liquid veins might explain this apparent excess diffusion. However, the analysis of Johnsen and others (2000) indicates that the required vein dimensions may be unrealistically large. Here, we model the diffusion of stable isotopes in polycrystalline ice and show that the predictions of Nye (1998) and those of Johnsen and others (2000) actually represent two end-members in a range of potential behavior. Our model determines which of these asymptotic regimes more closely resembles the prevailing conditions and quantifies the role of pre-melted liquid in the smoothing of isotopic signals. The procedure thereby ties together the two approaches and provides a rostrum for accurate analysis of isotope records and paleotemperature reconstructions.
Improved IPMC sensing by use of cation and through induced nano-to-micro scale surface cracks

Ionic Polymer Metal Composite (IPMC) is a nano-scale metal deposited ionic polymer and may be used as soft actuator and sensor. Numerous researches have been conducted to study IPMC as actuator. Many other applications like energy harvesting, impact sensing and velocity sensing use IPMC as a sensor, thus making it necessary to understand sensing nature of IPMC. It has been demonstrated that production of charge under the influence of mechanical deformation in IPMC, is a combined effect of chemical, mechanical and electrical response which may be affected by nature of existing cation and, conductivity and morphology of electrodes. This paper presents a comparison between the sensing behavior of IPMC under the influence of different cations like Li+, Na+ and H+. In addition, experiments were also performed to study the effect of nano-to-micro scale surface cracks in IPMC. It was also discovered that inducing nano-to-micro scale surface cracks in IPMC improves the sensing characteristics of IPMC. Experiments were also performed to compare the effect of electrode surface morphology and conductivity on sensing performance of IPMC. These effects were also compared for energy harvesting applications of IPMC.
Dielectric spectroscopy in agriculture

Abstract Reported measurements of the dielectric properties or permittivities over broad frequency ranges for some agricultural materials are cited, and graphical data from the cited literature are presented. They include 50-kHz to 12-GHz frequency-domain permittivity data for adult rice weevils and hard red winter wheat, time-domain reflectometry data for the same insects from 30 MHz to 1 GHz, frequency-domain data from 200 MHz to 20 GHz for adults of the lesser grain borer, 200-MHz to 20-GHz data for apple juice and fresh peaches, and 10-MHz to 1.8-GHz data, as a function of temperature, for whey protein gel and navel orange tissue. Interpretation of the data showed that selective dielectric heating of rice weevils in wheat could be expected between 10 and 100 MHz but not at microwave frequencies. For fresh fruit and vegetable tissues, temperature dependence of the dielectric constant was minimal at some frequency in the 20–120 MHz range with a positive temperature coefficient below that frequency and a negative temperature coefficient at higher frequencies. Between 10 and 300 MHz, the loss factor can be very well expressed as a linear function of the log of frequency and temperature. With further study dielectric spectroscopy may be useful in detecting product quality factors.
Evaluation of gastric ulcerations.

All gastric ulcers diagnosed during the period November, 1969–May, 1974, were prospectively evaluated by roentgenography, fiberoptic gastroscopy, directed biopsy, and brush cytology. Gastroscopy was performed routinely in patients with radiologic diagnosis of gastric ulcer or questionable findings, and in symptomatic individuals with negative roentgenograms. A total of 123/142 ulcers, 109 benign, 14 malignant, were available for complete follow-up. Gastroscopy was correct in 106 of 109 benign ulcers visualized. Roentgenoscopy demonstrated 91 of 109, of which 7 were incorrectly called carcinoma. Gross diagnosis was correct by gastroscopy in 11 of 14 malignant ulcers. Radiology visualized 6 of 14; gross diagnosis was correct in 1 of 6 (5 called benign). Directed gastroscopic biopsy was negative for malignant changes in all 109 benign and 3 of 14 malignant ulcers. Total complete gastroscopic diagnostic failures were 4 of 123, for an overall accuracy of 96.7%. Overall roentgenographic accuracy was 70.8%.
The inhibition of vesicular stomatitis virus protein synthesis by frog virus 3.

Abstract Heat-inactivated frog virus 3 (ΔFV 3) inhibited the synthesis of vesicular stomatitis virus (VSV) proteins in BHK cells by 40 to 60%. This inhibition was apparently a direct effect on translation because (i) inhibition occurred throughout the growth cycle of VSV and (ii) it did not depend on the ability of ΔFV 3 to inhibit transcription. The partial block in translation was sufficient to account for the ability of ΔFV 3 to depress VSV genome replication. Treatment with ΔFV 3 at 5 hr after VSV infection inhibited genome synthesis by 60 to 70%. However, there was only about 15% reduction in the yields of released infectious virions. A model is discussed to account for the resistance of PFU production to ΔFV 3 added at 5 hr postinfection despite the inhibition of genome RNA synthesis. Evidence is presented suggesting that ΔFV 3 may facilitate maturation of intracellular VSV nucleocapsids.
Alteration of the enzymology of chloral hydrate reduction in the presence of ethanol.

Abstract The enzymology of chloral hydrate reduction to trichloroethanol was studied in rat liver slices and homogenates. Two enzymes capable of reducing chloral hydrate are present in rat liver and by their properties were found to be aldehyde reductase and alcohol dehydrogenase. The alcohol dehydrogenase catalyzed reaction was very sensitive to the NAD/NADH ratio of the incubation medium and was found to be virtually incapable of performing the reduction with a simulated in vivo coenzyme ratio. The aldehyde reductase catalyzed reaction was relatively insensitive to the NADP/NADPH ratio. Hence, only one of the two possible enzyme systems appears to catalyze the reduction in vivo. Incubations performed with liver slices in the presence or absence of inhibitors and alternative substrates for the two enzyme systems indicated that in the absence of ethanol only aldehyde reductase catalyzed the reduction of chloral hydrate. About a 1.5-fold increase in the rate of reduction of chloral hydrate was observed when 40 mM ethanol was added to the liver slice incubation. Further, deuterium was incorporated into trichloroethanol when the incubations were performed with deuteroethanol. The increased rate of reduction and the deuterium incorporation were both prevented by the inclusion of alcohol dehydrogenase inhibitors (pyrazole and isobutyramide). Thus, in the presence of ethanol, both alcohol dehydrogenase and aldehyde reductase contribute to the reduction of chloral hydrate. Alcohol dehydrogenase is capable of reducing chloral hydrate in the presence of an oxidizable alcohol because it is converted into an enzyme—NADH complex which can then reduce the compound.
Surgical treatment of hypopharyngeal and cervical esophageal cancer.

Numerous methods have been employed for esophageal replacement after total pharyngolaryngectomy-esophagectomy. These have included the use of skin, as well as free transplantation or transposition of various abdominal viscera. The history and technical aspects of the procedures that have been used on the author's service are reviewed and results of 32 reconstructive operations are presented. Lower mortality and morbidity rates were obtained and palliation more consistently achieved with visceral transposition procedures than when the esophagus was reconstructed with skin. The 3-year cure rate of patients undergoing resection for cancer was 21%. Gastric transposition after extrathoracic total esophagectomy is the preferred procedure for suitable patients with post-cricoid and cervical esophageal carcinoma. Skin flaps are preferred for high hypopharyngeal tumors and in the poorest risk patients. Reversed gastric tube esophagoplasty and esophagocoloplasty are best employed for secondary rather than primary reconstruction.
The Post-Fuego Stratospheric Aerosol: Lidar Measurements, with Radiative and Thermal Implications

Abstract Fifteen lidar observations of the stratosphere aerosol were made between February and November 1975. All observations revealed the greatly increased particulate backscattering that followed the eruption of the volcano Fuego in October 1974. Vertical structure consisted initially of multiple layers, which later merged to form a single, broader peak. Nearly all of the increased scattering was confined to altitudes below 20 km. Hence, aerosol layer centroids in 1975 were typically several kilometers below their altitude prior to the eruption. Our observations began in mid-February, at about the time of maximum northern midlatitude influence of the volcanic injection. From late February on, both vertically integrated particulate back-scattering and the peak ratio of particulate to gaseous backscattering displayed approximately exponential declines, with mean 1/e lifetimes of eight and eleven months, respectively. These relatively short residence times are a combined consequence of the low altitude of...
Characteristics of intestinal metaplasia in the gastric cardia

Abstract OBJECTIVE: Intestinal metaplasia of the gastroesophageal junction is frequently grouped together with Barrett’s esophagus. The area of the gastroesophageal junction is comprised of the distal esophagus and the gastric cardia. The aim of the present study was to assess whether intestinal metaplasia in the distal esophagus and gastric cardia represent two different entities with a different set of risk factors. METHODS: Patients presenting for elective upper endoscopy were enrolled into a prospective study. The presence of gastritis and intestinal metaplasia was evaluated in gastric biopsies taken from the antrum, corpus, and cardia. Barrett’s esophagus was defined by the presence of any length of columnar mucosa above the gastroesophageal junction. RESULTS: Of 302 patients, 50 patients had intestinal metaplasia of the gastric cardia, 73 Barrett’s esophagus, and 116 erosive esophagitis. Men were more prone than women to develop Barrett’s esophagus or erosive esophagitis. Both conditions were also more common among whites than nonwhites. Smoking was particularly common among patients with Barrett’s esophagus. Patients with cardiac intestinal metaplasia did not share these demographic characteristics. The prevalence of daily reflux symptoms, erosive esophagitis, and Barrett’s esophagus was similar among patients both with and without cardiac intestinal metaplasia. However, atrophy and intestinal metaplasia of the gastric antrum and corpus were found more frequently among patients with than without cardiac intestinal metaplasia. CONCLUSIONS: Intestinal metaplasia of the gastric cardia is different from Barrett’s esophagus. Although cardiac intestinal metaplasia is closely associated with signs of gastritis in other parts of the stomach, gastroesophageal reflux disease does not seem to be a risk factor. A diagnosis of Barrett’s esophagus should not be made based on the presence of intestinal metaplasia within the cardiac portion of the gastroesophageal junction.
Epibulbar Lesions Among Bantus

We are impressed by the frequency of conjunctival and limbal lesions in the Congo. Al­ though most are benign, symptoms are often severe. Ash reported 1120 cases of epibulbar le­ sions. He found significantly more pterygia and pingueculae in black than in white pa­ tients. The basic pathology was mainly epidermalization of the conjunctival and corneal epithelium which may undergo further changes resulting in malignant dyskeratosis, papillomatosis, and carcinoma. Ash and Wilder reported 17 cases of epidermalization, 28 papillomas, and 42 carcino­ mas of the limbal epithelium. In 13 cases of epidermalization there was essentially leukoplakia with acanthosis, hyperkeratosis, and dyskeratosis. In four cases the picture re­ sembled Bowen's disease. Only one of the patients was black. Sugar and Kobernick reported 14 cases of irritative pingueculae, with six appearing clinically as leukoplakias. In three cases some acanthosis and parakeratosis were present. In two there was mainly a thickening of the epi­ thelium. In one case the epithelium was missing. Quere, Camain, and Lambert found a high incidence of malignant primary orbital and intraocular tumors in tropical Africa. They reported 44 advanced carcinomas of the conjunctiva, 36 of which were squamous cell carcinoma. Templeton stated that squamous cell car-
The Quantitative Distribution Of Gold In Skin During Chrysotherapy

Gold concentrations in epidermis, dermis, and whole skin were measured by neutron activation analysis after formation of suction bullae in 8 patients who had received protracted chrysotherapy. Epidermis contained 3% (median) of the gold content of whole skin. A direct correlation between cumulative gold dose and skin gold level was noted. These findings suggest that apparent gold concentrations in skin are influenced by the depth of the biopsy, the keratinous tissues have little affinity for gold, and that the gold storage capability of skin is not saturated by large cumulative doses of gold. The beneficial effect of gold in pemphigus may not be mediated at the site of blister formation.
Nucleic acid content and ultraviolet susceptibility of Tetrahymena pyriformis

Abstract 1. 1. The extent to which Tetrahymena pyriformis W accumulates nucleic acids and their precursors during heat treatment and the influence of such accumulated materials upon ultraviolet (UV) sensitivity of the protozoans was studied. 2. 2. At the end of heat treatment tetrahymenas contain double the amount of the deoxyribonucleic acid (DNA) precursors, deoxyribonucleosides and deoxyribonucleotides, present before heat treatment. The amount is maintained following the first synchronous division, but is reduced to the original amount by the second synchronous division. 3. 3. At the end of heat treatment a tetrahymena has almost double the amount of DNA present before heat treatment. This is partitioned between the daughters at the end of the first synchronous division. 4. 4. At the end of heat treatment a tetrahymena has more ribonucleic acid (RNA) than an untreated individual. The content of RNA is gradually reduced in the synchronous divisions following the end of heat treatment until the normal level is achieved. 5. 5. Division of tetrahymenas is delayed by irradiation, the delay increasing with dosage. Delay of the first division after irradiation is not marked but delay of the second and third divisions following irradiation is more noticeable. The effects of a given dosage of UV of wavelength 265 mμ retards division of tetrahymena more than a like dosage of wavelength 226 mμ. On the other hand, the latter radiations immobilize tetrahymenas much more readily than the former. 6. 6. The second and third divisions subsequent to irradiation with UV are progressively more delayed when tetrahymenas are irradiated with like dosages in the following physiological stages: at the end of heat treatment, before heat treatment, and after the first synchronous division. 7. 7. The greater resistance to UV radiations of tetrahymenas at the end of heat treatment than in other physiological states is correlated with their greater content of DNA in that stage. Thus the UV sensitivity is inversely proportional to the amount of DNA present per cell, and shows a direct relationship with the amount of DNA which a cell must synthesize before division. 8. 8. In spite of almost a doubled amount of deoxyribonucleotides and deoxyribonucleosides in individuals which have undergone the first synchronous division after heat treatment, resistance to UV is very low, indicating no correlation of UV resistance with these compounds. The block in DNA synthesis may be in the incorporation of these precursors into DNA. 9. 9. Since UV of wavelength 226 mμ has no differential effect on division of tetrahymenas before and at the end of heat treatment, yet it retards division, an effect of UV at a locus other than nucleic acid synthesis is suggested.
Operative and endoscopic pancreatography in the diagnosis of pancreatic cancer

X-rays of the pancreatic duct can now be obtained by a nonoperative endoscopic approach (endoscopic retrograde cholangiopancreatography-ERCP). After more than 2 years experience we have found that the pancreatic duct can be visualized in 85 to 90% of patients. This test is used to detect pancreatic carcinoma in the symptomatic patient and in searching for an operative pancreatic lesion in a patient with known recurrent or chronic pancreatitis. Many of these patients have pain or a transiently elevated amylase; a few have steatorrhea or abnormalities of the duodenal sweep on barium meal. Stenosis or obstruction of the main pancreatic duct with or without proximal duct dilation are the characteristic abnormalities noted in pancreatic carcinoma. A rare pancreatic tumor which is not in juxtaposition with the duct will have a normal pancreatogram although the common duct may be obstructed by cholangiography as it passes through the head of the pancreas. In patients with chronic pancreatitis it may be difficult to differentiate an inflammatory from a neoplastic stricture by either operative or endoscopic pancreatography. In the future, cytologic and biochemical examination of the pancreatic secretions obtained at ERCP may increase the accuracy of diagnosing carcinoma.
Bremsstrahlung in the scattering of low-energy electrons by neutral atomic systems

By elementary methods, the cross section for electron-atom and electron-molecule bremsstrahlung is computed in the limit when the incident electron energy is much less than Ry. The procedure employs the classical soft-photon emission probability formula for general (h/2pi)(omega), yielding a simple expression for the bremsstrahlung cross section in terms of the total elastic scattering cross section. The validity of the method is discussed, and results are compared with more elaborate and accurate calculations. Comparison is made with ('free-free') opacity calculations for the associated process at the temperature (6300 K) of the solar atmosphere. For chi sub omega = (h/2pi)(omega)/kT = 1, the computed absorption coefficient is within 2, 7, and 12 percent of accurate calculations for scatterings by H, He, and H2, respectively. The general dependence of the opacity on chi sub omega is described well by the simple formula, although the error is larger for higher chi sub omega; it is suggested that the inaccuracy at high frequencies is due to the failure of the soft-photon approximation.
Implantation of collagen plugs into incisional keratotomies

Abstract Purpose: To evaluate whether supplementing incisional keratotomy bulk or gape with a biocompatible material enhances the refractive effect. Setting: Refractive Surgery Laboratory, Massachusetts Eye and Ear Infirmary, Boston. Methods: Collagen punctal plugs were implanted into astigmatic keratotomy (AK) incisions in the right eyes of five rabbits and six adult cats. The left eyes had AK only and served as controls. Results: Some of the postoperative corneal topographic measurements suggested an enhanced refractive effect. At 1 month, histology demonstrated no remaining implant material and no inflammation in or near the incisions. Conclusions: Implanting a biocompatible material into AK incisions in two live animal models appears to be safe and may enhance the effect of the incisions. Further study is needed to quantify the magnitude and duration of any refractive effect.