cssi/SciSciGPT-SciSciNet huggingface dataset:
Environmentally induced restructuring of polymer surfaces and its influence on their wetting characteristics in an aqueous environment

Abstract In the conventional methods of estimating the wetting characteristics of solids from contact angle experiments, the surface energetic properties of the solid are assumed to be identical in the environments of both the surrounding medium and probe fluids. While this assumption is suitable for solids which possess rigid surface structures (such as glasses, ceramics, and metals for example), it is generally inapplicable to polymeric solids, since the surfaces of the latter are relatively mobile so as to be able to adopt considerably different configurations in different environments. Based on a recognition of this feature of polymeric surfaces, a sequence of contact angle experiments is suggested to estimate: (a) the instantaneous as well as equilibrium surface energetic properties of a polymeric solid in an aqueous environment and (b) the time required for the polymeric surface to attain its equilibrium wetting characteristics in the aqueous environment. In order to illustrate the applicability of the suggested contact angle procedure, it is necessary to prepare model polymeric surfaces, which are smooth in surface texture, nonporous, and also chemically homogeneous. Such model surfaces were prepared in this study, by radio frequency sputter deposition of thin solid films of oxidized fluorocarbon compounds (from a Teflon FEP target) onto the smooth surfaces of highly polished, single crystal silicon substrates. The estimation of the wetting characteristics of the sputtered polymer films in an aqueous environment was then carried out by the suggested contact angle procedure. The results of the contact angle experiments indicate that the solid-water interfacial free energy of the sputtered polymer film which was initially equilibrated in an octane environment, decreases from an instantaneous value of 50.88 dyn/cm to an equilibrium value of 26.59 dyn/cm, over a duration of about 24 h. Such a change in the solid-water interfacial free energy of these model polymeric surfaces can arise due to a time-dependent reorientation of the buried polar groups of the solid from its bulk to its surface, when it is placed in contact with a strongly polar liquid like water. This interpretation was found to be consistent with the results of ESCA characterization, which indicated that the outer surface layers of the sputtered polymeric specimen contained a fair amount of the polar oxygen atoms that are capable of reorienting themselves from either the interior of the solid to its surface or vice versa, depending on their surrounding environment.
Improved parameter estimates based on the homodyned K distribution

Quantitative techniques based on ultrasound backscatter are promising tools for ultrasonic tissue characterization. There is a need for fast and accurate processing strategies to obtain consistent estimates. An improved parameter estimation algorithm for the homodyned K distribution was developed based on SNR, skewness, and kurtosis of fractional- order moments. From the homodyned K distribution, estimates of the number of scatterers per resolution cell (mu parameter) and estimates of the ratio of coherent to incoherent backscatter signal energy (k parameter) were obtained. Furthermore, angular compounding was used to reduce estimate variance while maintaining spatial resolution of subsequent parameter images. Estimate bias and variance from Monte Carlo simulations were used to quantify the improvement using the new estimation algorithm compared with existing techniques. Improvements due to angular compounding were quantified by the decrease in estimate variance in both simulations and measurements from tissue-mimicking phantoms and by the increase in target contrast. Finally, the new algorithm was used to derive estimates from 2 kinds of mouse mammary tumors for tissue characterization. The new estimation algorithm yielded estimates with lower bias and variance than existing techniques. For a typical pair of parameters (mu = 5 and k = 1), the bias and variance were reduced 67% and 16%, respectively, for the mu parameter estimates and 79% and 37%, respectively, for the k parameter estimates. The use of angular compounding further reduced the estimate variance, e.g., the variance of estimates for the mu parameter from measurements was reduced by a factor of approximately 90 when using 120 angles of view. Finally, statistically significant differences were observed in parameter estimates from 2 kinds of mouse mammary tumors using the new algorithm. These improvements suggest estimating parameters from the backscattered envelope can enhance the diagnostic capabilities of ultrasonic imaging.
Finite Element Implementation of Anisotropic Quasi-Linear Viscoelasticity Using a Discrete Spectrum Approximation

The objective of this work was to develop a theoretical and computational framework to apply the finite element method to anisotropic, viscoelastic soft tissues. The quasilinear viscoelastic (QLV) theory provided the basis for the development. To allow efficient and easy computational implementation, a discrete spectrum approximation was developed for the QLV relaxation function. This approximation provided a graphic means to fit experimental data with an exponential series. A transversely isotropic hyperelastic material model developed for ligaments and tendons was used for the elastic response. The viscoelastic material model was implemented in a general-purpose, nonlinear finite element program. Test problems were analyzed to assess the performance of the discrete spectrum approximation and the accuracy of the finite element implementation. Results indicated that the formulation can reproduce the anisotropy and time-dependent material behavior observed in soft tissues. Application of the formulation to the analysis of the human femur-medial collateral ligament-tibia complex demonstrated the ability of the formulation to analyze large three-dimensional problems in the mechanics of biological joints.
Serum stability and non-specific binding of technetium-99m labeled diaminodithiol for protein labeling.

Abstract Previously we investigated the use of DTPA-coupled proteins to simplify labeling with 99mTc but especially to improve the stability of the label. These investigations have now been extended to include several N2S2 ligands such as N,N′-bis(2-methyl-2-mercaptopropyl)ethylenediamine (DADT) and a novel ligand of similar structure with a propylene bridge between two amines, 2-hydroxy-N,N′-bis(2-methyl-2-mercaptopropyl)propylenediamine (DADT-3C-2OH). The condition of labeling of free ligand (pH, buffer and tin concentration) was optimized to provide 100% chelation with 99mTc at reasonable ligand concentrations (100 μg/mL or less). Labeling was determined by paper chromatography, reverse-phase and size-exclusion HPLC. After incubation in fresh serum, 37 °C for 24 h, repeat analysis showed less than 5% dissociation of the chelate. By contrast, the DTPA chelate shows instability towards oxidation during this period. DADT derivatized on an ethylene carbon showed almost identical serum stability as DADT itself whereas when derivatized on a nitrogen greater instabilities were apparent. Using identical labeling conditions, free DADT was chelated in the presence of IgG at different ligand: protein molar ratios. Non-specific binding of 99mTc to IgG at a 10:1 DADT-HM:IgG molar ratio was as little as 5% and was essentially zero at a 2:1 DADT:IgG molar ratio when labeling was by transcomplexation from 99mTc-EDTA. The DADT-3C-2OH ligand showed superior performance both in regard to serum stability and the absence of non-specific binding. In conclusion, the N2S2 ligands form more stable chelates with 99mTc than does DTPA with reduced non-specific binding and may therefore represent an attractive alternative for labeling proteins with 99mTc by the bifunctional chelate approach.
microRNA-mediated control of cell fate in megakaryocyte-erythrocyte progenitors

Lineage specification is a critical issue in developmental and regenerative biology. We hypothesized that microRNAs (miRNAs) are important participants in those processes and used the poorly understood regulation of megakaryocyte-erythrocyte progenitors (MEPs) in hematopoiesis as a model system. We report here that miR-150 modulates lineage fate in MEPs. Using a novel methodology capable of profiling miRNA expression in small numbers of primary cells, we identify miR-150 as preferentially expressed in the megakaryocytic lineage. Through gain- and loss-of-function experiments, we demonstrate that miR-150 drives MEP differentiation toward megakaryocytes at the expense of erythroid cells in vitro and in vivo. Moreover, we identify the transcription factor MYB as a critical target of miR-150 in this regulation. These experiments show that miR-150 regulates MEP fate, and thus establish a role for miRNAs in lineage specification of mammalian multipotent cells.
A New Look at U.S. Agricultural Productivity Growth, 1800–1910

A debate has recently been re-ignited over the pace of long-run productivity growth in nineteenth-century agriculture. Before 1966 the view was one of accelerated productivity over the course of the century, and this view was confirmed by the statistics on farm gross product published in 1960 by Marvin Towne and Wayne Rasmussen. The appearance in 1966 of Stanley Lebergott's labor force series changed this traditional perspective. When combined with Towne and Rasmussen's output figures, Lebergott's figures suggested that productivity growth was slower after the Civil War than before, calling into question the more plausible pattern of postbellum increases. A few historians were skeptical of these new findings, but were unable to dispute the seemingly solid foundation upon which they were built. Finally in 1993, Thomas Weiss argued that the skeptics were in fact correct to be wary of Lebergott's revisions.
The ecological determinants of reinforcement in the guinea pig

Abstract The hypothesis that constraints on the parameters of free feeding are the source of motivation in feeding behavior was explored in Guinea pigs. The effect of effort (FR size) on meal frequency, meal size and rate of eating was investigated when reinforcement consisted of an entire meal or a small portion of a meal. Frequency of feeding decreased and the duration and rate of eating increased when an entire meal was available. Frequency of meals was unaffected and rate of lever pressing and duration of meals increased when reinforcement consisted of a single food pellet. These data were taken to argue that there is a common pattern of changes in feeding behavior across species with respect to these variables and the value of these variables can be taken to describe the properties of different ecological niches.
Rapid Methods of Determining Cooling Rates of Iron and Stony Iron Meteorites

Two rapid and simple methods have been developed for determining the approximate cooling rates of iron and stony-iron meteorites in which kamacite formed by diffusion-controlled growth along planar fronts. The first method requires only measurements of the mean kamacite bandwidth and the bulk nickel content. The second method requires the determination of the nickel composition near the taenite-kamacite interface with an electron microprobe.
Note on the effect of the nuclear energy gap on the optical model potential

The effect of the energy gap on the optical model potential was calculated by combining Migdal's Green-type derivation with Watson's expression for the potential. It was found to be negligible in the case of nuclear matter. (D.L.C.)
Hypoxanthine transport in normal and hypoxanthine guanine phosphoribosyltransferase (HGPRT) deficient diploid human lymphoblasts

Abstract We have examined the possible relation between hypoxanthine guanine phosphoribosyltransferase (EC 2.4.2.7., HGPRT) activity and hypoxanthine transport in the normal human lymphoblast line MGL8 and two HGPRT- mutant lines derived from it. The mutant line MGL8A29 (L8A29) had considerable amounts of material cross-reacting immunologically to HGPRT, while mutant MGL8A18 (L8A18) had none. In the normal cells, hypoxanthine is taken up by both a saturable and non-saturable process. Kinetic studies show that the velocity of transport is much lower than HGPRT activity, while both have similar values of Km. In the two mutant lines, we failed to demonstrate saturable transport, and the rates of hypoxanthine uptake by these cells were directly proportional to its concentration in the medium. Active HGPRT molecules appear to be related to the saturable transport process.
Stability of traveling waves for Hamilton–Jacobi equations with finite speed perturbations

Abstract We prove nonlinear stability of planar shock for general Hamilton–Jacobi equations with finite speed perturbation. Here we use energy estimates. It is shown that the solution connecting a weak shock is asymptotically stable under small perturbations.
Reductive nitrosylation of MoO2(dedtc)2 by hydroxylamine

The reaction of MoO2(dedtc)2 (1, dedtcN,N-diethyl dithiocarbamate) with hydroxylamine in methanol produces Mo(NO)(dedtc)3 (3) the structure of which has been determined by X-ray diffraction. © 2000 Elsevier Science S.A. All rights reserved.
Relationship between medical genetics and public health: Changing the paradigm of disease prevention and the definition of a genetic disease

This article is a US Government work and, as such, is in the public domain in the United States of America.
Proton therapy with concomitant capecitabine for pancreatic and ampullary cancers is associated with a low incidence of gastrointestinal toxicity

AbstractBackground. To review treatment toxicity for patients with pancreatic and ampullary cancer treated with proton therapy at our institution. Material and methods. From March 2009 through April 2012, 22 patients were treated with proton therapy and concomitant capecitabine (1000 mg PO twice daily) for resected (n = 5); marginally resectable (n = 5); and unresectable/inoperable (n = 12) biopsy-proven pancreatic and ampullary adenocarcinoma. Two patients with unresectable disease were excluded from the analysis for reasons unrelated to treatment. Proton doses ranged from 50.40 cobalt gray equivalent (CGE) to 59.40 CGE. Results. Median follow-up for all patients was 11 (range 5–36) months. No patient demonstrated any grade 3 toxicity during treatment or during the follow-up period. Grade 2 gastrointestinal toxicities occurred in three patients, consisting of vomiting (n = 3); and diarrhea (n = 2). Median weight loss during treatment was 1.3 kg (1.75% of body weight). Chemotherapy was well-tolerated with...
Tentative chip decision-feedback equalizer for multicode wideband CDMA

We investigate a chip-level minimum mean-square-error (MMSE) decision-feedback equalizer (DFE) for the downlink receiver of multicode wideband code-division multiple-access systems over frequency-selective channels. First, the MMSE per symbol achievable by an optimal DFE is derived, assuming that all interchip interference (ICI) of the desired user can be eliminated. The MMSE of DFE is always less than or at most equal to that of linear equalizers (LE). When all the active codes belong to the desired user, the ideal DFE is able to eliminate multicode interference (MCI) and approach the performance of the single-code case at high signal-to-noise ratio (SNR) range. Second, we apply the hypothesis-feedback equalizer or tentative-chip (TC)-DFE in the multicode scenario. TC-DFE outperforms the chip-level LE, and the DFE that only feeds back the symbols already decided. The performance gain increases with SNR, but decreases with the number of active codes owned by the other users. When all the active codes are assigned to the desired user, TC-DFE asymptotically eliminates MCI and achieves single-user (or code) performance at high SNR, similarly, to the ideal DFE. The asymptotic performance of the DFE is confirmed through bit error rate simulation over various channels.
Multiple specimen J-integral testing at intermediate rates

The effect of experimental technique on the measurement of elastic-plastic fracture toughness has been investigated. Multiple-specimenJ-integral measurements have been performed at an intermediate loading rate. One set of measurements was conducted completely under computer/servohydraulic control, while another set was performed with a fixture that mechanically limits the maximum displacement and load. For the single condition tested, a minimal effect was measured on the initiation fracture toughness. An increased effect was seen on the measured crack-growth-resistance (J-R) curve as the amount of crack growth increased. The consequences of such testing methods in terms of general (intermediate loading rate) testing will be discussed.
Archaeology and the prehistoric origins of the Ghana empire

Archaeological investigations in southern Mauretania have revealed a wealth of rather spectacular stone masonry villages which were occupied by prehistoric cultivators as early as 1000 B.C. It is argued that the inhabitants of these villages were Negro and very probably Soninke, and that the basic elements of their culture had developed without major influences from outside the area. The apparent sophistication and complexity of this cultural manifestation, combined with the close fit of developments in this area with Carneiro's theory of state formation, suggests that this prehistoric complex represented at least a powerful chiefdom which embodied many of the characteristics of subsequent West African states. The first demonstrable outside influences in the area began about 600 B.C. with the arrival of Libyco-Berbers from North Africa. Rather than causing still further cultural advances, the initial effect of this contact was the collapse of this sociopolitical organization. But with subsequent adjustment, plus the potential from trans-Saharan trade carried out by the North Africans, the basic, pre-existing pattern re-emerged, resulting eventually in a second and much more powerful African political organization in this area – the Ghana Empire.
Health Beliefs and Practices in an Isolated Polygamist Community of Southern Utah

Short Creek is a largely closed and isolated community on the border between Utah and Arizona, made up of the sister towns of Hildale, Utah, and Colorado City, Arizona. Beginning from childhood, the 6,000 or so members of the Fundamentalist Church of Jesus Christ of Latter-Day Saints (FLDS) are brought up in a lifestyle of plural marriage, meaning a marriage among one man and more than one woman, and are surrounded by their peers in “the covenant.” A lifestyle of plural marriage is likely to affect the health of community members, but its effects have not been studied because of the community’s isolation and distrust of outsiders. This paper addresses several questions that arise in contemplating the health of the Short Creek community: What are the health beliefs in this community, and what are their historical bases? Where do families seek medical care, and for what or at what threshold of illness or injury? What is the attitude of care providers serving this community, and how are the providers viewed by the community? More broadly, this paper examines the ways in which polygamy configures health. In order to meet this objective, this paper aims first to provide a brief account of this community’s history and demographic profile, followed by a discussion of health care in this community and how it is affected by the practice of plural marriage, with the data comprised of qualitative interviews with health care providers to the community. The goals of this project are to gain a rich, historically nuanced understanding of the health of community members, and to identify directions for further academic and policy research. Our findings indicate that health in this community is shaped by limited resources, an attitude of health fatalism, and a profound insularity and corresponding isolation from the outside world.
MEMS Micro Valve for Space Applications

We report on the development of a micro-electro-mechanical systems (MEMS) valve that is designed to meet the rigorous performance requirements for a variety of space applications, such as micro-propulsion, in situ chemical analysis of other planets, or microbiology. These systems often require very small yet reliable silicon valves with extremely low leak rates and long shelf lives. Also, they must survive the perils of space travel, which include unstoppable radiation, monumental shock and vibration forces, as well as extreme variations in temperature. Currently, no commercial MEMS valve meets these requirements. At JPL, we are developing a piezoelectric MEMS valve that attempts to address the unique problem of space. We begin with proven configurations that may seem familiar. However, we have implemented some major design innovations that should produce a superior valve. The JPL micro-valve is expected to have an extremely low leak rate, limited susceptibility to particulates, vibration or radiation, as well as a wide operational temperature range.
Multidecadal (1959–1997) changes in Skeletonema abundance and seasonal bloom patterns in Narragansett Bay, Rhode Island, USA

Abstract A 38-year time series (January 1959 to May 1997) of weekly observations of abundance of the marine diatom Skeletonema spp. and related plankton habitat parameters in lower Narragansett Bay, Rhode Island was compiled and analyzed. A statistical change point test identified two different abundance regimes characterized by a ca. 45% decline in Skeletonema abundance. In the first 260 months of the time series (January 1959 to August 1980), the mean deseasonalized Skeletonema abundance was 2137 cells ml− 1, which declined to 1128 cells ml− 1 in the final 201 months (August 1980 to May 1997) of the time series. The decline was greatest during the winter–spring bloom period; Skeletonema abundance in March declined from a mean of ca. 3300 cells ml− 1 prior to the change-point to ca. 700 cells ml− 1 after the change point. Skeletonema exhibited three types of annual abundance patterns: winter–spring, summer and autumn bloom peaks. A decline in winter–spring Skeletonema abundance was part of a shift away from winter–spring bloom dominated annual cycles in the 1960s to summer bloom dominated annual cycles in the 1990s. Of 25 years suitable for analyses, Skeletonema winter–spring bloom dominated in 12 years, summer blooms dominated in ten years and autumn blooms dominated three years. Winter–spring Skeletonema bloom years tended to be bright, windy, cold, and have lower copepod (Acartia hudsonica) abundance in the first quarter, and were cool and had high A. hudsonica abundance in the fourth quarter. In contrast, during summer and fall Skeletonema bloom years the first quarters were darker, warmer, less windy and accompanied by higher first quarter A. hudsonica abundance. In summer and fall bloom years the fourth quarters were warm and had above-mean river flow and low A. hudsonica abundance. The observed first quarter environmental differences between winter–spring and summer–fall bloom years (i.e., water temperature, wind, light) may be partially regulated by changes in weather induced by large-scale atmospheric circulation patterns. Years in which the North Atlantic Oscillation (NAO) index was relatively low (mean = − 1.4) tended to have colder winters, and winter–spring bloom dominated Skeletonema annual cycles; years with high NAO index (> + 1.1) featured warmer winters and summer or autumn Skeletonema blooms.
Synthesis of Histidinoalanine: A Comparison of β-Lactone and Sulfamidate Electrophiles

Previous syntheses of histidinoalanine (HAL) have led to mixtures of regioisomers and/or stereoisomers. For example, opening of N-Cbz-d-serine-β-lactone (6) with Boc-l-His-OMe (5) gave a 2:1 mixture of τ- and π-regioisomers. The sulfamidate 10, derived from N-benzyl-d-serine methyl ester (11), was reacted with Boc-l-His-OMe (5) to give the τ-HAL derivative 17 as a single isomer in 57% yield. A similarly prepared τ-HAL 19, bearing protecting groups that were all hydrogenolytically labile, led to the free bis-amino acid, τ-l-histidinyl-d-alanine (τ-4), as a salt-free standard for amino acid analysis.
Calculation of the dispersion contribution to the interaction energy of two hydrogen molecules at large but finite distances

Abstract An attempt to calculate the dispersion energy between two hydrogen molecules by a perturbative procedure and from a simple product of the individual molecular Hartree-Fock wavefunctions (ab initio, using small basis sets) has been made. The results are very much smaller than the semi-empirical calculations but, qualitatively, it has been found that the main contribution is due to the first virtual orbital, that seems to justify the semi-empirical ideas. Our values, though still small, increase strongly if we use the expectation values of the respective hamiltonian for the energy denominator instead of the energy eigenvalues of the Hartree-Fock hamiltonians.
Epoprostenol (PGI2, Prostacyclin) During High-Risk Hemodialysis: Preventing Further Bleeding Complications

The frequency of hemodialysis-associated hemorrhage was studied prospectivelyin two successive, parallel, heparin-controlled studies using epoprostenol (PGI2; average dose, 4.1 ng/kg- mm) as the sole antithrombotic agent. Sixty-three patients with active or recently active bleeding underwent 163 hemodialysis treatments in each of which prospective bleeding risk was assessed. PGI2 was associated with up to 50% overall reduction in the frequency of bleeding, particularly in the highest risk circumstances. PGI2 also allowed successful completion of the full, pros pectively prescribed hemodialysis time in the most treatments (82% versus 93% with heparin). Furthermore, the efficiency of hemodialysis using PGI2, as indicated by the reduction in concentration of blood urea nitrogen and serum creatinine, was equal to that using heparmn, even though there was a tendency toward modest reduction in residual volume of the hollow fiberdialyzerand slightly more frequent early termination of treatment from dialyzer clottingwith PGI2. No severe vasodilatory side effects of PGI2 were observed during these studies. Hypotension was equally frequent durir.g hemodialysis with heparin as with PGI2. The current results suggest that PGI2 should be considered as a substitute for heparin during high-risk hemodialysis because PGI2 may reduce the incidence of dialysis-associated bleeding without severe adverse side effects.
Intraoperative reflectance oximetry in burn patients.

Objective. Transmission oximetry sites for intraoperative monitoring are frequently difficult to find in burn patients, as standard transmission oximetry sites are often burned or contained within the operative field. The objective of this study was to determine if reflectance oximetry is of potential value in monitoring this group of patients.Methods. A total of 16 operative procedures in a group of acutely burned adult and pediatric patients with an average age of 9.7 years (range, 10 months to 37 years), average burn size of 42% of the body surface (range, 15% to 94%), and average weight of 34.2 kg (range, 9 to 100 kg) were done with simultaneous transmission and reflectance oximetry monitoring.Results. During these 16 procedures in a diverse group of acutely burned adult and pediatric patients, there was no significant difference in saturations derived from transmission and reflectance oximetry probes. In smaller children, adequate signal for reflectance probe monitoring was often detected in hyperemic sites, such as healed partial thickness burn.Conclusions. This is the first published report documenting both the clinical use of the reflectance oximetry in burn patients and the clinical use of the Nellcor Oxisensor II RS-10 reflectance oximetry probe (Nellcor Corporation, Hayward, CA). This technique can facilitate the intraoperative monitoring of acutely burned adult and pediatric patients in whom standard transmission oximetry sites are difficult to find.
Second virial coefficients as a measure of protein--osmolyte interactions.

The cytoplasm contains high concentrations of cosolutes. These cosolutes include macromolecules and small organic molecules called osmolytes. However, most biophysical studies of proteins are conducted in dilute solutions. Two broad classes of models have been used to describe the interaction between osmolytes and proteins. One class focuses on excluded volume effects, while the other focuses on binding between the protein and the osmolyte. To better understand protein–smolyte interactions, we have conducted sedimentation equilibrium analytical ultracentrifugation experiments using ferricytochrome c as a model protein. From these experiments, we determined the second virial coefficients for a series of osmolytes. We have interpreted the second virial coefficient as a measure of both excluded volume and protein–osmolyte binding. We conclude that simple models are not sufficient to understand the interactions between osmolytes and proteins.
The Introduction of Domestic Technology in the White House from 1800 to 1952

OBJECTIVE: The purpose of the article was to trace the history of domestic technology in the White House from 1800 to 1952. RESEARCH DESIGN: Data were gathered in two ways: a search of historical documents and government reports and an on-site examination of White House files. ANALYSIS: The discussion is structured thematically and chronologically to show the changes that occurred over time. KEY FINDINGS: The changes coincided with changes in Presidents and available technology. CONCLUSION: The study provides valuable information for interior design historians; design educators; historians of presidents, first families, technology, and the White House; and curators. Similar methodologies could be used in describing and comparing the technological developments in other historic homes.
Different release of cytokines into the cerebrospinal fluid following surgery for intra- and extra-axial brain tumours

To elucidate the role of cytokines in brain repair processes and in local inflammation after neurosurgical procedures, cerebrospinal fluid (CSF) samples from 8 patients with intra-axial tumours and 8 patients with extra-axial tumours were analysed for interleukin (IL)-1beta, IL-1 receptor antagonist (IL-1ra), IL-6, IL-8, IL-10, and tumour necrosis factor (TNF)-alpha at the beginning and after surgery. Levels of IL-6 and IL-8 increased dramatically in all patients just hours after surgery and fell during subsequent days. IL-1beta was found only in low amounts in the CSF of both patient groups. Other cytokines demonstrated different courses. In patients with intra-axial tumours IL-1ra peaked two to four hours after surgery with a subsequent decrease. In patients with extra-axial tumours there was a continuous low-level IL-1ra release into the CSF without a peak. TNF-alpha was not present in detectable levels in the CSF after surgery for extra-axial tumours but was found to peak two to four hours after surgery for intra-axial tumours. IL-10 was detected in the CSF of both patient groups, but a higher peak was seen after surgery for extra-axial tumours. These results suggest different requirements for the cytokine response and an involvement of different cell types in cytokine release. However, the analysis of the CSF from both patient groups showed no differences in cell counts and populations, with a mild pleocytosis being present in both patient groups after surgery. Therefore, we conclude that after surgery for extra-axial tumours cytokines were predominately produced by non-immune cells stimulated through hypoxia or mechanical irritation. After surgery for intra-axial tumours with a significant brain injury immune cells — activated by necrotic material —seem to be involved in the process of cytokine synthesis. In these cases an additional IL-1ra and TNF-alpha peak was found and these cytokines may be markers for cerebral injury.
Fault-tolerant control of power grids for security and availability

This paper presents a framework for fault-tolerant control of a modernizing electric power grid. The motivation for the new development hinges on the potential benefits of utilizing fast control devices and high sample rate measurement devices to enhance the grid's resilience beyond that offered by the traditional protection devices. A set of quantifiable security indices based on a fault-coverage concept is used for selection of control actions and the times to exert them. Viewed as a discrete state stochastic process, the grid's long-run availability is shown to be an increasing function of the security indices, whereas the security indices are decreasing functions of the level of uncertainty in the grid state information, the the level of imprecision of its dynamic model. An example of an aggregated two-area power system is used to demonstrate the principle and the computation involved in achieving a minimum risk control. It also illustrates how uncertainties cause delay in control actions and reduction in the critical clearance time in order to maintain a prescribed level of security.
Micro-electrolytic iodination of polypeptide hormones for radio-immunoassay

Abstract A micro-electrolytic method for the radioactive iodination of polypeptide hormones is described (insulin, growth hormone, thyroid-stimulating hormone). A micro-cell was constructed permitting the labelling of minute amounts of hormones with 125I to high specific activity for use in radioimmunoassay. The purification of the labelled hormone was accomplished by Sephadex G-75 filtration and verified by high voltage chromatoelectrophoresis.
Intrarenal pressures remain low with placement of a dual lumen catheter for retrograde irrigation to induce renal hypothermia

Objective To determine whether placement of a 10 French dual lumen catheter produces a low-pressure collecting system during retrograde irrigation to induce renal hypothermia. Indication for the study is as a potential adjunct for partial nephrectomy.
Binary optics from a ray-tracing point of view

An exact raytrace (Snell''s law refraction) of the discontinuous surfaces of kinoforms (surface relief lenses) can explain their optical performance at different wavelengths without diffraction. A phase-based merit function generated by raytracing can be used to design and optimize systems containing both kinoform and conventional optical surfaces.
Kibos: A microcomputerized system for the continuous collection and analysis of behavioral data

Abstract This paper describes the design and use of an observation and recording system in which data on behavioral patterns exhibited by socially-living primates are recorded as present or absent within recurring units of time. Behavioral observations and initial editing are carried out on-line on a microcomputer. The checklist of observed behavious is open-ended and modifiable, as required by the selection of subject species and by experimental goals. Summary statistical reports are available immediately after data entry has been completed. Further editing and organization of data files take plance when data are transferred to a large computer. The virtues of this system are its ease of use by observers who can be trained rapidly, its cost-effectiveness, and its ability to record simultaneously a larger number of behaviors than other systems usually can. Included are examples of data-analytic programs which are executed after data have been transferred to a large computer.
Wading Through the Quagmire of Religious History

How should we teach religious history? What is the impact of our methodology on what, and on how, our students learn? Is there a methodology that cultivates an awareness of the multiculturalism and the need for deeper social interaction that characterizes many of our classrooms? This essay proposes and briefly explores the potential value of empathetic engagement as a pedagogical tool in response to these concerns. A specific application of empathetic engagement is made to teaching and learning about the history of American Catholicism.
Cyanooximes as effective and selective co-crystallizing agents

The ability of cyanooxime-based synthons to act as versatile synthetic tools for the construction of co-crystals is demonstrated through the preparation and structural characterization of seven co-crystals. Cyanooximes can bind effectively to both five-membered and six-membered N-heterocyclic hydrogen-bond acceptors, and they also display selectivity towards the best acceptor (as determined using semi-empirical AM1 calculations) in ditopic compounds.
Growth Requirements of Symbiont-Free and Symbiont Lambda-Bearing Paramecium octaurelia 299 for Folic Acid and Biopterin

We investigated the growth requirements of symbiont-free and symbiont lambda-bearing Paramecium octaurelia stock 299 for folic acid and biopterin in chemically defined culture medium. Symbiont-free P. octaurelia required both folic acid and biopterin for growth. In the absence of these substances growth of symbiont-free P. octaurelia failed after the first transfer, whereas symbiont lambda-bearing P. octaurelia could be maintained indefinitely in serial subculture. In the absence of folic acid and biopterin, sulfanil-amide inhibited growth of the symbiont lambda-beating protozoa. In the presence of folic acid and biopterin, the antiobiotic selectively inhibited growth of lambda symbionts but did not affect growth of the protozoa. In both cases, inhibition by sulfanilamide was reversed by addition of p-aminobenzoic acid to the medium. These results support our earlier finding that folic acid is required for growth of symbiont-free P. octaurelia 299 and that growth of the lambda-bearing strain without exogenous folate denoted synthesis of folic acid by the symbionts. In addition, it appears that the symbionts produce sufficient biopterin to meet the needs of the host protozoon for growth.
Pathological left-handedness and preserved function associated with a slowly evolving brain tumor

The authors report the serial neuropsychological evaluations of a patient with acquired left-handedness who had a massive brain tumor that infiltrated the entire temporal and posterior parietal lobes of the left hemisphere. Although the patient had pre-operative impairment of non-verbal memory, follow-up assessment 31 and 66 months after the tumor was resected revealed cognitive functions to be in the high-average to superior range. This case demonstrates the sparing of neuropsychological functions that can be seen with a slowly evolving lesion. The authors suggest that such functional sparing may be due to transfer of function rather than to the residual function of tumor-infiltrated neuronal tissue. Possible mediators of functional preservation include slow lesion growth, the patient's youth at disease onset and the large size of the lesion.
Computational Dynamics of Ordinary Differential Equations

Discrete schemes, used to perform time integration of ODE’s, are expected to exhibit qualitatively ‘true’ dynamics in terms of the solutions and their stability. In past years, it has been discovered that such discretizations may cause spurious steady states and some explicit schemes may produce ‘computational chaos.’ In this study, we show that implicit time integration schemes, such as the backward Euler method, can also produce computationally chaotic solutions. Furthermore, we show that the opposite phenomenon may also take place both for explicit and for implicit schemes: computationally generated ‘spurious order’ may replace the true chaotic solution before the scheme becomes linearly unstable. The numerical solution may become chaotic again as the discretization step is further increased. The spurious computational order and chaos are discussed by solving low-dimensional dynamical systems, as well as a large system of ODE representing the solution to the Navier-Stokes equation. Our results support the point of view that the deviations in the behavior of the computed solution from the true solution has deterministic character with the time step playing the role of an artificial bifurcation parameter.
Effect of Postmortem Time and Temperature on the Release of Lysosomal Enzymes and Their Possible Effect on Bovine Connective Tissue Components of Muscle

The influence of postmortem time and incubation temperature on the release of lysosomal enzyme activity and their effect on the muscle connective tissue have been investigated. Semimembranosus muscles from nine steers were restrained and held at 2°C (C) for 60 hr; five portions of each muscle were elevated to 37°C (HT) for different 12-hr sequences of the 60 hr. It was found that HT incubated samples showed a greater release of lysosomal enzymes (β-galactosidase and β-glucuronidase), regardless of the time postmortem when high temperature conditioning occurred. The inclusion of hyaluronidase or β-galactosidase in the sample incubation solution resulted in an increase in the dissolution of collagen fibers by collagenase, which indicates that lysosomal glycosidases may also participate in the dissolution of collagen fibers during postmortem aging.
Serum albumins - unusual allergens

Background Albumins are multifunctional proteins present in the blood serum of animals. They can bind and transport a wide variety of ligands which they accommodate due to their conformational flexibility. Serum albumins are highly conserved both in amino acid sequence and three-dimensional structure. Several mammalian and avian serum albumins (SAs) are also allergens. Sensitization to one of the SAs coupled with the high degree of conservation between SAs may result in cross-reactive antibodies in allergic individuals. Sensitivity to SA generally begins with exposure to an aeroallergen, which can then lead to cross-sensitization to serum albumins present in food.
A Signal Processing Technique for Measurement of Multimode Waveguide Signals: An Application to Monitoring of Reaction Bonding in Silicon Nitride

A system that uses ultrasonic techniques to monitor the reaction bonding of silicon nitride is described. Reaction bonding of silicon nitride takes place in a nitrogen atmosphere at temperatures up to 1400°C. As with many sensors used in hostile environments, it is difficult to design the ultrasonic sensor in a way that provides optimal clarity of the signal. The sensing system must be designed within the physical limitations on access to the furnace. Ultrasonic probes that accommodate limited access to the silicon nitride sample have been designed and ultrasonic signals acquired during processing, albeit with significant noise and complexity in the signal. Signal processing techniques are used which make it possible to measure changes in phase velocity and attenuation during reaction bonding. Because of variability in the measured velocity and attenuation, the method of signal processing presented is applicable to those cases where it is not possible to redesign the probe for optimal clarity of the ultrasonic signal. This technique demonstrates the potential to perform measurements using signals that would have been considered intractable in the past. Data obtained from ultrasonic monitoring are suitable for use as input to a manufacturing process control feedback loop.
MHC3 Factors Predicting Potentially Inappropriate Psychotropic Prescribing for the Elderly

With the widespread use of psychotropics in the elderly, issues related to the availability and appropriate use of psychotropic medications in older patients have become a concern from both therapeutic and economic viewpoints. OBJECTIVE: The purpose of this study was to examine the factors predicting potentially inappropriate psychotropic prescribing for the elderly in office-based practice. METHODS: This study utilized data from the National Ambulatory Medical Care Survey (NAMCS) 1995 to examine psychotropic agents that should be generally avoided in the elderly, based on the criteria previously developed through a consensus process. These included diazepam, chlordiazepoxide, meprobamate, flurazepam, pentobarbital, secobarbital, and amitriptyline. Psychotropic drugs considered inappropriate based on an excessive dosage or excessive duration of therapy were not examined due to the limitations of the data source. National visit estimates were derived based on the patient sampling weight provided for the NAMCS. RESULTS: Approximately 2.03 million (95% CI, 1.70–2.36 million) visits by the elderly involved potentially in appropriate psychotropic medications. Only two potentially inappropriate psychotropic medications, secobarbital and pentobarbital, were not prescribed for the elderly by office-based physicians. The remaining five potentially inappropriate medications accounted for 16.85% of the visits involving psychotropic medications, with amitriptyline alone accounting for over 10%. The most frequently prescribed potentially inappropriate psychotropic classes were antidepressants and antianxiety agents. The logistic analysis results revealed that patient characteristics (injury visit), drug characteristics (number of medications and drug classes), and physician characteristics (specialty and region) predict potentially inappropriate psychotropic prescribing. CONCLUSION: The psychotropic prescribing patterns in ambulatory settings raise concerns regarding the quality of care for the elderly with psychiatric illnesses. The predictive factors may be used to design effective educational and regulatory strategies to improve prescribing for the elderly.
Longevity Speaks: Observations from Long-Serving Counseling Center Directors

This article summarizes the online responses of 28 counseling center directors who have directed the same center for at least 20 years. In general, respondents report ample job satisfaction. Major changes on their watch include increases in student pathology and demand for appointments; major non-changes include the developmental issues of college students and the essence of the treatment process. If given the chance, most long-term directors would do it all over again. They are generous in their advice for younger colleagues, most memorably in the suggestion, “Relax and enjoy the profession that you have selected.”
Melt–rock reaction in the lower oceanic crust and its implications for the genesis of mid-ocean ridge basalt

Primitive cumulates from a 2–3 Ma old gabbro massif exposed in the Kane Megamullion (23°N, Mid-Atlantic Ridge) contain abundant clinopyroxene with high Mg# (86–91). Such magnesian clinopyroxenes have hitherto been taken to signify crystallization at elevated pressures. Kane clinopyroxenes, however, are dominantly oikocrysts that overgrow olivine and plagioclase, indicating crystallization occurred at low pressure. The oikocrysts have textures and compositions indicative of disequilibrium processes. First, many of the oikocrysts enclose resorbed plagioclase with lower anorthite contents than plagioclase in the host rock, and olivine is notably absent as a chadacryst despite being abundant in the host rock. Second, the oikocryst minor element compositions are inconsistent with equilibrium growth from a MORB melt. These data indicate that high-Mg# clinopyroxene in the Kane gabbros formed as a result of reaction between primitive cumulates and migrating melt in the lower oceanic crust, with clinopyroxene and secondary plagioclase growing at the expense of olivine and primary plagioclase. Thus high-Mg clinopyroxene does not result from high-pressure crystallization as has been inferred previously. Assimilation–fractional crystallization modeling indicates that melts undergoing such reactions are enriched in Al2O3 and MgO and depleted in CaO and SiO2. This effect is similar to that expected for fractional crystallization of MORB at elevated pressures, and reacted melts yield higher calculated pressures than starting melts. This suggests that the CaO–Al2O3–MgO–SiO2 relationships of MORB may result from melt–rock reaction, and that calculated pressures of MORB fractionation are overestimated as a result. Melt–rock reaction in the lower oceanic crust may thus account for both lines of evidence for high-pressure fractionation of MORB.