cssi/SciSciGPT-SciSciNet huggingface dataset:
RAMIFICATIONS OF PREDATOR AVOIDANCE: PREDATOR AND HEAVY- METAL-MEDIATED COMPETITION BETWEEN TADPOLES AND SNAILS

We examined how the effects of competition between snails (Lymnaea pulustris) and Columbia spotted frog (Rana luteiventris) tadpoles are mediated by predatory bluegill sunfish (Lepomis macrochirus) and heavy metals. We raised snails and tadpoles in outdoor mini-ecosystems containing lead-, zinc-, and cadmium-contaminated soil from the EPA Superfund site in the Silver Valley of northern Idaho. To some treatments we added water from the tanks of sunfish that had fed on tadpoles and snails. Unexpected indirect effects occurred in polluted environments. We found a habitat shift by snails and tadpoles due to the response of tadpoles to predaceous fish odor. This shift decreased tadpole ingestion of metal-rich sediments and increased metal ingestion by snails. Heavy metals and fish odor therefore altered competitive interactions between snails and tadpoles. Metal-exposed tadpoles metamorphosed at an older age than non-metal-exposed animals. Metal exposure did not affect snail survival, growth, or recruitment. In the absence of heavy metals tadpoles reduced snail recruitment. Because heavy metals disproportionately harmed tadpoles, the negative effects of tadpoles on snails were ameliorated in polluted environments. The presence of snails did not alter tadpole development but did increase metal loads in tadpoles. We also tested the ability of snails to detect and respond to chemical cues emanating from crushed snails, an extract of crushed snails, and sunfish. Snails changed their behavior in response to crushed snails, but not to sunfish. Heavy-metal-exposed snails did not alter their behavior. Tadpoles altered their behavior when exposed to sunfish that had fed on tadpoles but did not respond to sunfish that had not fed on tadpoles. We found that heavy metal toxicants and predator odor cause behavioral changes and can alter competitive interactions between snails and tadpoles. We also showed that, due to indirect effects, pollution exposure for a given species may be modified both by the presence of competitors, and also by species that are neither competitors nor perceived as predators.
Approximations in the quasiparticle random phase evaluation of double beta decay rates

Within the quasiparticle random phase approximation, we compare two-neutrino double beta decay amplitudes calculated with zero-range and finite-range nucleon-nucleon interactions. We find that if, as is customary, interaction constants are fit to energies of giant Gamow-Teller states and to β+ strengths, the two interactions lead to very similar two-neutrino double beta amplitudes. We discuss additional approximations related to the inclusion (or neglect) of the Hartree-Fock part of the pairing interaction, and to the treatment of differences between the initial and final nuclear ground states. The numerical values of the amplitudes depend more on the way these approximations are made than on the form of the nucleon-nucleon force.
Experimental and numerical investigation of non-premixed tubular flames

Abstract Non-premixed tubular flames are established using the opposed tubular burner for the first time, which enables the quantitative study of curvature effects on flame behavior. A detailed structural investigation using the spontaneous Raman scattering technique is conducted on flames with constant curvature using 15% H2 diluted by N2 against air at various stretch rates. The measured temperature and major species concentrations agree well with the numerical prediction, and this validates the numerical model. Comparing with the numerical results of the opposed-jet flat flame, the tubular flame data show that the curvature weakens the effects of preferential diffusion for the diluted hydrogen flames where the curvature is concave towards the fuel stream. To further prove this discovery, near-extinction non-premixed tubular flames using different types of fuels are also studied. Hydrogen flames (Le 1) prefer concave curvature, which is opposite to the hydrogen flames, and cellular structures appear throughout the burner’s operational range. These phenomena confirm that for flames with Le 1. Curvature has minimal effects on tubular non-premixed flames with Lewis number close to unity. The comparison between experimental and calculated extinction conditions also supports the above conclusions.
High Stress Responsivity Predicts Later Blood Pressure Only in Combination With Positive Family History and High Life Stress

High cardiovascular responsivity to stressors has not consistently improved prediction of later blood pressure increases beyond the predictive effects of baseline pressure. Animal models suggest that genetic susceptibility to hypertension and frequent stress exposure are important modulating factors in stress-related hypertension. Thus in 103 men originally tested at age 18 to 22 years and reassessed 10 years later, interactive effects of genetic susceptibility (defined as 1 or more hypertensive parents) with high stress responsivity (defined as top 25% on the basis of blood pressure and cardiac responses during both reaction time and cold pressor tasks) were examined in relation to follow-up systolic and diastolic levels and to change in blood pressure status from normal (diastolic<80 mm Hg) to marginally elevated (diastolic 85 to 95 mm Hg). Men with the combination of high stress response and hypertensive parents demonstrated higher systolic (P<0.05) and diastolic levels (P<0.05) at follow-up, and they showed a 7-fold increase (7.5, 95% confidence intervals 2.3, 24.3; P<0.001) in relative risk of change in blood pressure status versus men with no family history and a 3-fold increase (3.8, confidence intervals 1.5, 9.6; P<0.004) versus less stress-responsive men who also had hypertensive parents. In 65 men who also provided ratings of daily stress, family historyxstress responsivityxdaily stress interactions were significant in predicting follow-up systolic and diastolic levels (P<0.006 and 0.03, respectively), with highest pressure levels seen when high life stress was reported by high stress responders and/or men with hypertensive parents. In conclusion, results suggest that stress responsivity as a long-term predictor is modulated by both genetic and environmental factors.
Clusters, phason elasticity and entropic stabilization: a theoretical perspective

Personal comments are made about the title subjects, including: the relation of Friedel oscillations of Hume–Rothery stabilization; how calculations may resolve the random-tiling versus ideal pictures of quasicrystals; and the role of entropics apart from tile-configurational.
The chemisorption of methanol on Cu films on ZnO(000¯1)-O

The interactions of methanol with well-defined Cu films on the oxygen-terminated ZnO(000¯1)-O surface have been studied, mainly using temperature programmed desorption (TPD). The Cu films, which were from submonolayer to multilayer in coverage, had been structurally characterized in previous studies using XPS, LEIS, ARXPS, LEED and work function measurements, and by CO, H2O and formic acid adsorption. On clean Cu films methanol is adsorbed reversibly, desorbing at 200–260 K from atom-thick Cu islands, and at ∼ 155 K from multilayer islands preannealed to ∼ 550 K. In this respect, the atom-thin islands resemble Cu(110) sites and multilayer islands resemble Cu(111), consistent with behavior of other adsorbates. On oxygen-predosed multilayer films (preannealed to ∼ 600 K), methanol reacts to form methoxy species which decompose at 395 K to yield formaldehyde and hydrogen in TPD, also like Cu(111). Multilayer films preannealed to >750 K show a decrease in the peak area for methoxy decomposition which correlates with the loss of Cu area due to severe clustering. Oxygen-predosed Cu islands which are but one Cu atom thick show no clear evidence for a methoxy state in TPD. This suggests that oxygen atoms on such atom-thin Cu islands are poor Bronsted bases relative to Oa on bulk Cu surfaces, consistent with results for adsorbed water. Results on high-area Cu/ZnO catalysts are discussed in the light of these new results.
Predictive value of monitoring parameters in fetal surgery.

Abstract Background/Purpose: The choice of monitoring parameters in fetal surgery has thus far been based on feasibility rather than on predictability. Ideally, monitoring should be noninvasive, have a rapid response time and high sensitivity, and be applicable to open and endoscopic techniques. Herein, the authors studied the response of several parameters to standardized episodes of fetal ischemia and stress. Methods: Eight time-dated fetal lambs (110 days, term, 145 days) were used. Under general anesthesia, a balloon occluder was placed around the umbilical cord. Pulse oximetry (POx + heart rate, HR), electrocardiography (ECG), direct oximetry (DOx), and blood pressure (BP) were recorded continuously. After stabilization, the umbilical cord was completely occluded for 5 seconds, then released. False-negative recordings were defined as failure of a parameter to respond to umbilical occlusion; false-positive episodes were defined as 10% change in value over ≤10 seconds during stabilization (baseline) period. Results: The fetuses were monitored for an aggregate of 358 minutes. Baseline DOx was 64% ± 5%, POx, 66% ± 16%; HR, 141 ± 18 beats per minute (bpm); systolic BP (SBP), 51 ± 3 torr; and diastolic BP (DBP), 38 ± 2 torr. During umbilical occlusion (n = 15), SBP increased to 56 ± 3 torr and DBP to 43 ± 2 torr at 0.5 seconds, then returned to baseline at 8.0 seconds. A decrease was seen in DOx (start at 3.5s, maximum Δ 9.9 ± 1.5% at 10.5 seconds) and POx (start at 4.2 seconds, maximum Δ 7.3 ± 2.4% at 20.5 seconds). Heart rate showed Conclusions: Direct intravascular oximetry and blood pressure provide a prompt and reliable response to acute fetal stress, but are too invasive for routine use. Bradycardia is an insensitive and late sign of fetal distress. Pulse oximetry has a rapid response time (
Targeted TLR9-activation/STAT3-blocking abrogates immunosuppressive functions of myeloid-derived suppressor cells from late-stage prostate cancer patients

Recent clinical advances underscored that elimination of tumor-induced immunosuppression is prerequisite for successful therapy of advanced human cancers. The myeloid-derived suppressor cells (MDSCs) are one of the major populations limiting T cell-mediated antitumor immune responses in late-stage solid tumors, such as castration-resistant prostate cancers (CRPCs). Targeting MDSCs proved challenging due to their heterogeneity and phenotypic similarities with other myeloid cell lineages. Here, we identify a population of granulocytic MDSCs, which accumulate in patients' blood during progression of prostate cancer from localized to metastatic disease. The CRPC-associated MDSCs potently inhibit proliferation, IFN-γ and Granzyme-B production in autologous CD8+ T cells. Importantly, the MDSCs in blood and in lymph nodes of CRPC patients show high levels of activated STAT3 transcription factor, which is a crucial immune checkpoint regulator. We previously generated an original method to silence genes specifically in TLR9+ myeloid cells using CpG-siRNA conjugates [1,2]. Now, we demonstrate that the CpG-STAT3siRNA is also effectively internalized by human MDSCs and induces STAT3 silencing without the need for transfection reagents. Our further studies demonstrated that two-pronged TLR9-activation/STAT3-blocking by CpG-STAT3siRNA inhibits immunosuppressive effects of CRPC-MDSCs on CD8+ T cells, while both TLR9 triggering or STAT3 inhibition alone have only minimal effects. The reversal of MDSC immunosuppression by CpG-STAT3 siRNA results from reduced expression and enzymatic activity of Arginase I, a downstream STAT3 target gene. Overall, our study demonstrates the feasibility of overcoming immunosuppression in CRPC patients using CpG-STAT3siRNA strategy to alleviate effects of MDSCs. We anticipate that our strategy to reverse MDSC-mediated immunosuppression without depleting myeloid cell populations will generate safer and more effective immunotherapy for late-stage, metastatic prostate cancers and potentially other solid tumors. This project described was supported by the National Cancer Institute of the National Institutes of Health under award number R01CA155367 and by the Department of Defense Prostate Cancer Research Program under award number W81XWH-12-1-0132 to M.K.
Effects of TCDD on the EGF receptor of XB mouse keratinizing epithelial cells

TCDD was found to cause a marked inhibition of 125I-epidermal growth factor (EGF) binding to its receptor on the cell surface of XB mouse keratinizing epithelial cells (XB cells) cultured in vitro. The EC50 concentration was estimated to be on the order of 3 x 10(-11) M 24 hours after TCDD administration. As early as 12 hours after the addition of 10(-9) M of TCDD, XB cells showed signs of a decline in 125I-EGF binding levels. The level of such EGF receptor downregulation reached a maximum at 24 hours, continued until day 2, but completely recovered by day 3. This was accompanied by a rise in protein kinase activities, particularly those of the protein tyrosine kinases during the initial period of 6-24 hours. To test the hypothesis that the EGF receptors of the cells, by showing TCDD-induced symptoms of downregulation, actually are being activated and triggering EGF-like signals, we examined the effects of both TCDD and exogenously added EGF on cell morphology, colony formation degree of keratinization, the pattern of activation of protein kinases and de novo protein synthesis, and EGF receptor phosphorylation. Based on the similarity of cell responses to these between TCDD- and EGF-treated cells, we concluded that TCDD, directly or indirectly, causes activation of the EGF receptor. In contrast, 12-O-tetradencanoylphorbol-13-acetate (TPA), which is known to downregulate EGF receptors by blocking their protein tyrosine kinase, produced dissimilar end results. The balance of evidence support the notion that the action of TCDD in this cell line is tightly coupled to the activation of the EGF receptor and that one of the key consequences of such a biochemical change is that it signals these cells to commit to terminal differentiation.
The epidemiology and pathogenesis of necrotizing enterocolitis

Necrotizing enterocolitis (NEC), a syndrome characterized by crepitant necrosis of the bowel, has emerged as the most common neonatal gastrointestinal emergency in many countries of the world. In the United States, NEC strikes 1 to 8% of patients admitted to neonatal intensive care units, almost all of whom are premature infants. The incidence is low in certain countries wity a low premature birth rate, e.g., Japan. Two theories of pathogenesis are: the Santulli theory, which implicates three factors: ischaemia, bacteria and substrate; and the Lawrence theory, which stresses the injurious role of bacterial toxins on the immature gut of the preterm infant. Clinical and experimental evidence support each of the theories, but neither theory can explain certain clinical phenomena, particularly the resistance to NEC manifested by more than 90% of preterm infants, who never develop the syndrome. A unifying hypothesis of pathogenesis and a mathematical model of NEC are outlined. Because clustering of cases may occur, the design of clinical trials of preventive measures for NEC must include simultaneous control infants.
The commercialization of RISC: Strategies for the creation of dominant designs

Abstract Reduced instruction set computers (RISC) recently have mounted a strong challenge to the complex instruction set computers (CISC) that previously dominated the computer workstation industry. This change has had a tremendous impact on systems developers, and may have far-reaching implications for the structure of the U.S. microprocessor industry. Intel and Motorola, who dominate the CISC microprocessor market, ignored or failed to respond to early evidence of the advantages of RISC architectures and have lost the initiative in this fast-growing market to Sun Microsystems and other producers of workstations who have developed RISC microprocessors. This paper discusses the development and commercialization of RISC architectures, focusing on the licensing strategies of Sun and MIPS Computer Systems, two pioneers in RISC microprocessors. Rather than an exogenous event, to which managers must adapt, the history of RISC suggests that firms can pursue strategies that aid in the establishment of their products as dominant designs. In the case of RISC, licensing has assumed particular significance because of the important complementarities between hardware and applications software, which results in network externalities. In such technologies, the innovator may gain significant advantages from a relatively permissive attitude toward “giving away” important intellectual property.
Echocardiographic Capture of Right Ventricular Wall Rupture During Inferior Wall Acute Myocardial Infarction

We present the case of a 57-year-old woman with no previous cardiovascular history in whom fatal right ventricular wall rupture was diagnosed by bedside echocardiography early in the management of an inferior wall acute myocardial infarction.
Delayed seed dispersal in Pinus torreyana (Torrey pine)

Torrey pine exhibits a pattern of seed release intermediate between an open and closed-cone species. It was found that the cones open at maturity, but that seed fall from some cones continues for up to 13 years. Approximately 77% of the total seed crop was present in age classes one or more years past the time of seed maturity.
Measurements of the grain boundary energy and anisotropy in tin

The three-dimensional (3-D) geometry of the triple junction formed between two solid Sn-rich particles and a Pb-rich liquid matrix is used to measure the interfacial energy and its anisotropy for individual grain boundaries. The anisotropy is determined using a Cahn-Hoffman capillarity vector analysis of the energy balance at a triple junction. The absolute solid-solid grain bondary energy for each individual boundary is then determined by using the known value for the solid-liquid energy. A total of 136 boundaries are analyzed, with 46 of them forming grain boundaries. The remaining boundaries are found to be wetted boundaries with thin-liquid films formed between the two particles. A correlation between the low interfacial energy and the probability of occurrence for that disorientation is also observed. We also show that the anisotropy, as quantified by the magnitude of the torque term, is a significant portion of the total interfacial energy, especially for low energy boundaries. The degree of twist vs tilt of the boundaries is also analyzed. As expected, there are more tilt boundaries within the system than twist boundaries and most of the low energy boundaries have a mixed tilt-twist character.
MicroRNA biogenesis and cellular proliferation.

Given the fundamental roles of microRNAs (miRNAs) in physiological, developmental, and pathologic processes, we hypothesized that genes involved in miRNA biogenesis contribute to human complex traits. For 13 such genes, we evaluated the relationship between transcription and 2 classes of complex traits, namely cellular growth and sensitivity to various chemotherapeutic agents in a set of lymphoblastoid cell lines. We found a highly significant correlation between argonaute RNA-induced silencing complex catalytic component 2 ( AGO2 ) expression and cellular growth rate (Bonferroni-adjusted P AGO2 expression was found to be correlated with multiple drug sensitivity phenotypes. Furthermore, small interfering RNA knockdown of AGO2 resulted in cellular growth inhibition in an ovarian cancer cell line (OVCAR-3), supporting the role of this miRNA biogenesis gene in cell proliferation in cancer cells. Expression quantitative trait loci mapping indicated that genetic variation (in the form of both single-nucleotide polymorphisms and copy number variations) that may regulate the expression of AGO2 can have downstream effects on cellular growth–dependent complex phenotypes.
A critical assessment of the political preference function approach in agricultural economics

The political preference function (PPF) approach has been used often in the agricultural economics literature in attempts to explain the causes of farm policy. The fundamental assumption of PPF studies is that government selects levels of policy instruments such that it maximizes a function of interest groups' welfare measures for the purpose of acquiring maximum political support. PPF studies often use the familiar neoclassical constrained maximization problem to measure relative political powers of interest groups involved in policy determination. Some weaknesses of the PPF approach have been discussed in the literature (Gardner, 1989; Alston and Carter, 1991; and von CramonTaubadel (VCT), 1992 **). While each of these critiques provides valuable insight into PPF methodology and its limitations, none of them clearly explains the simple, fundamental structure of the PPF framework. This neglect of certain fundamentals has led to confusion in the litera-
Performance evaluation of spatial compounding in the presence of aberration and adaptive imaging

Spatial compounding has been used for years to reduce speckle in ultrasonic images and to resolve anatomical features hidden behind the grainy appearance of speckle. Adaptive imaging restores image contrast and resolution by compensating for beamforming errors caused by tissue-induced phase errors. Spatial compounding represents a form of incoherent imaging, whereas adaptive imaging attempts to maintain a coherent, diffraction-limited aperture in the presence of aberration. Using a Siemens Antares scanner, we acquired single channel RF data on a commercially available 1-D probe. Individual channel RF data was acquired on a cyst phantom in the presence of a near field electronic phase screen. Simulated data was also acquired for both a 1-D and a custom built 8x96, 1.75-D probe (Tetrad Corp.). The data was compounded using a receive spatial compounding algorithm; a widely used algorithm because it takes advantage of parallel beamforming to avoid reductions in frame rate. Phase correction was also performed by using a least mean squares algorithm to estimate the arrival time errors. We present simulation and experimental data comparing the performance of spatial compounding to phase correction in contrast and resolution tasks. We evaluate spatial compounding and phase correction, and combinations of the two methods, under varying aperture sizes, aperture overlaps, and aberrator strength to examine the optimum configuration and conditions in which spatial compounding will provide a similar or better result than adaptive imaging. We find that, in general, phase correction is hindered at high aberration strengths and spatial frequencies, whereas spatial compounding is helped by these aberrators.
Technological deliberation in a democratic society: The case for participatory inquiry

Far too little systematic attention has been devoted to the ability of citizens to participate meaningfully in an age dominated by complex technologies and expert decisions. Citizen protests against technological threats have led to practices of participatory inquiry that allow people to voice opinions on issues that directly affect their lives. The implied extra time and cost of the inquiry process has been worth while in many instances. More active steps should be taken to integrate the approach formally into technological policy and decision-making. Copyright , Beech Tree Publishing.
Structures and Characterization of Organoclay-Epoxy-Vinylester Nanocomposites

The field of polymer-clay nanocomposites has attracted considerable attention as a method of enhancing polymer properties and extending their utility. Layered silicates dispersed as a reinforcing phase in a polymer matrix are one of the most important forms of such inorganic-organic nanocomposites, making them the subject of intense research. We have recently prepared several thermoset-based nanocomposites with improved thermal and mechanical properties. This paper is primarily focused in studying the effects of nano clay particles such as montmorillonite on improving mechanical and thermal properties of the polymer matrix composite. Epoxy and vinyl ester nanocomposites were prepared by adding different weight percentages (0.5%, 1%, 2%, 5% and 10%) of montmorillonite nano clay particles to epoxy and vinyl ester matrices. The results show significant improvements in mechanical and thermal properties of the nanostructured materials with low loading of organo silicates. Thermal property measurement includes dynamic mechanical analysis (DMA). Mechanical properties such as flexural strength and flexural modulus of polymer matrix were improved in nano structured materials owing to their unique phase morphology and improved interfacial interactions. Molecular dispersion of the layered silicate within the cross-linked matrix was verified using Wide Angle X-Ray Diffraction (WAXD) and Transmission Electron Microscopy (TEM) revealing the intercalated nanocomposites were formed.Copyright © 2002 by ASME
Congenital Cervical Cysts, Sinuses, and Fistulae in Pediatric Surgery

Congenital cervical anomalies are essential to consider in the clinical assessment of head and neck masses in children and adults. These lesions can present as palpable cystic masses, infected masses, draining sinuses, or fistulae. Thyroglossal duct cysts are most common, followed by branchial cleft anomalies and dermoid cysts. Other lesions reviewed include median ectopic thyroid, cervical teratomas, and midline cervical clefts. Appropriate diagnosis and management of these lesions requires a thorough understanding of their embryology and anatomy. Correct diagnosis, resolution of infectious issues before definitive therapy, and complete surgical excision are imperative in the prevention of recurrence.
Calculation of electron impact excitation and ionization of

We present results from R-matrix with pseudo-states (RMPS) and convergent close-coupling (CCC) calculations for electron-impact excitation from and direct ionization of the ground state of the ion. The CCC and RMPS results are in very good agreement with each other. The long-standing discrepancy between theory and experiment for the total ionization cross section is unresolved, with the RMPS calculations supporting the present and earlier CCC results of Bray. The present 2P excitation results are in good accord with those of Mitroy and coworkers, but the values for the 3S, 3P and 3D cross sections are substantially different. In our view, the excitation cross sections for the n = 3 and n = 4 states have been predicted accurately from threshold to 1 keV for the first time.
Action of 1,25-dihydroxyvitamin D3 on calcium balance and bone turnover and its effect on vertebral fracture rate

In postmenopausal osteoporotics, malabsorption of calcium is associated with reduced levels of serum 1,25-dihydroxyvitamin D. Metabolic studies have shown that calcium absorption can be normalized and calcium balance improved after administration of oral doses of synthetic 1,25-dihydroxyvitamin D3 (Rocaltrol®) 0.25 μg twice daily. Further studies performed at two centers compared the effect of Rocaltrol® 0.25 μg twice daily versus placebo on vertebral fracture rates in osteoporotics. A significant reduction in vertebral fracture rates was seen at the end of 1 year. Those patients who continued on Rocaltrol® for a second and third year showed a progressive decrease in vertebral fractures. Rocaltrol®, administered at a dose of 0.25 μg twice daily, seldom causes hypercalcuria or hypercalcemia in osteoporotic patients on a typical calcium intake of 700 to 800 mg/d. Careful measurements of renal function over a period of 3 years in patients treated with Rocaltrol®, 0.25 μg twice daily, showed no deterioration in renal function. These data suggest that 1,25-dihydroxyvitamin D3 is a useful therapy in the management of patients with postmenopausal osteoporosis, particularly those who have malabsorption of calcium. We found that it improves calcium balance, reduces the vertebral fracture rate, and is safe to use provided that the dietary calcium is monitored and does not exceed 800 mg/d.
Spherical ensembles of gold nanoparticles on silica: electrostatic and size effects

Core–shell ensembles of citrate-stabilized gold nanoparticles (20–80 nm) on submicron silica cores (330–550 nm) have been prepared by electrostatic self-assembly with shell packing densities as high as ϕ = 0.55.
The Electrophysiologic Effects of Propafenone Hydrochloride in the Neonatal Canine

ABSTRACT: The electrophysiologic effects of the new antiarrhythmic agent, propafenone, were investigated in 10 mongrel canine neonates, ages 5 to 11 days. Utilizing standard His bundle recording and stimulation techniques, assessments of sinus and atrioventricular (AV) node function and atrial, AV nodal, and ventricular refractory periods were performed prior to (control) and after cumulative intravenous doses of 1, 2, and 4 mg/kg of propafenone. Propafenone depressed the spontaneous heart rate and prolonged the postatrial pacing recovery times. AV nodal function was depressed as manifested by Wenckebach periodicity occurring at slower pacing rates, increases in AV nodal conduction time, and increases in AV nodal refractoriness. Atrial and ventricular refractory periods were prolonged significantly in a dose-dependent fashion. Prolongation of the His-Purkinje conduction time occurred at the highest dose. Thus, propafenone exerts a generalized depressant effect on neonatal myocardial conduction and refractoriness which suggests that this agent may be useful in the therapy of atrial and ventricular dysrhythmias in the immature heart.
Morphological Basis for a Mechanical Linkage in Otolithic Receptor Transduction in the Frog

Observations made with a scanning electron microscope confirm the binding of the stereocilia to a matchhead-like bulbous terminal at the apex of the kinocilium in frog saccular receptor cells. Since the kinocilium is shown to rest on a portion of the receptor cell that lacks the rigid cuticular base of the stereocilia, movenment of the ciliary ensemble results in a "plunging-like" effect of the kinocilium which produces a distension of the membranc at its base. This membrane distension is envisaged as bringing about the ionic conductance changes necessary for the production of a generator potential and, thus, for the transduction of movement into vestibular nerve activity.
A thrombin–cross‐reactive anticardiolipin antibody binds to and inhibits the anticoagulant function of activated protein C

Objective To test the hypotheses that some thrombin-reactive anticardiolipin antibodies (aCL) may bind to protein C (PC) and/or activated PC (APC), and that some of the PC- and APC-reactive aCL may inhibit PC activation and/or the function of APC. Methods We studied the reactivity of patient-derived monoclonal aCL with PC and APC. We examined the effects of the reactive antibodies on PC activation and on the activity of APC in plasma coagulation. Results Five of 5 patient-derived, thrombin-reactive monoclonal aCL bound to PC and APC. In addition, 1 patient-derived monoclonal antiprothrombin antibody (APT) that displayed aCL activity and reacted with thrombin also bound to PC and APC. Of these 6 PC- and APC-reactive aCL/APT, all failed to inhibit PC activation, but 1 (CL15) shortened the plasma coagulation time in the presence of exogenous APC and thus inhibited the anticoagulant function of APC. Conclusion Most of the thrombin-reactive aCL in patients with antiphospholipid syndrome may bind to PC and APC. Of the APC-reactive aCL, some (like CL15) may inhibit the anticoagulant function of APC and are thus likely to be prothrombotic in the host.
Magnetic trapping of strongly-magnetized Rydberg atoms

Effective magnetic moments of drift Rydberg atoms in strong magnetic fields are obtained for different energy and angular-momentum states. Classical two-body trajectory calculations and quantum-mechanical one-body calculations are employed. For heavy atoms such as rubidium, the trapping dynamics can largely be explained by the net magnetic moment due to the cyclotron and the magnetron motion of the Rydberg electron. In light Rydberg atoms such as hydrogen, the intrinsic two-body nature of the dynamics becomes manifest in that the ionic motion significantly contributes to the effective magnetic moment. Also, light drift Rydberg atoms exhibit an anisotropic response to field-inhomogeneities parallel and transverse to the magnetic-field lines. The results are relevant to magnetic trapping of Rydberg atoms in strong-magnetic-field atom traps.
A physical model study of jointed rock mass strength under uniaxial compressive loading

Abstract Jointed rock mass strength is investigated through physical modeling using model material blocks subjected to only uniaxial compressive loading. Jointed model material blocks exhibited different failure modes depending on the joint configurations. Orientation of the joint sets played a significant role related to the modes of failure. It was possible to obtain a strong non-linear relation between the jointed model mass strength and the fracture tensor component to cover the strengths resulting from all the different failure modes observed in the investigation. The fracture tensor component was used to obtain the combined effect of number of joint sets, joint density, and distributions of size and orientation of the joint sets in a chosen direction. Needed future research are suggested to generalize the promising rock mass strength criterion obtained in the performed research.
Comparison of FCT with other numerical schemes for the burgers equation

Abstract The flux corrected transport (FCT) method is used to solve the linear and nonlinear Burgers Equations and to compare with other commonly used explicit methods such as the central difference (CD), the upwind (UW), and the predictor corrector or MacCormack (MC) schemes. The results show that the FCT scheme exhibits the best behavior for the linear as well as nonlinear cases. The amount of numerical diffusion is the least for the FCT scheme compared to the other schemes and more importantly there are no non-physical oscillations.
The Natural History of Idiopathic Subfoveal Choroidal Neovascularization

Purpose: To study the long-term natural history of idiopathic subfoveal choroidal neovascularization (CNV) in young patients. Methods: A retrospective survey of 19 consecutive patients with idiopathic subfoveal CNV diagnosed in an urban eye hospital and a single practice. Results: Twenty-three (26%) of 87 consecutive patients with idiopathic CNV demonstrated subfoveal CNV. Nineteen patients with subfoveal involvement were followed for a median of 87 months (range, 5–230 months). On initial examination, the median best-corrected Snellen visual acuity was 20/100 (range, 20/40-counting fingers); at final examination, the median visual acuity was 20/70 (range, 20/20-counting fingers). A total of 95% of patients had stable or significantly improved visual acuity, whereas only 5% had significant visual loss. Size of the CNV was the only variable associated with long-term final visual acuity. Lesions 1 disc area or smaller at the time of initial fluorescein angiography were more likely to be associated with a final visual acuity of 20/60 or better and less likely to be associated with a final visual acuity of 20/200 or worse ( P = 0.038) as compared with larger lesions. These results were confirmed with multiple logistic regression analysis ( P = 0.027). Fellow eyes remained unaffected during the follow-up period. Conclusions: The natural history of idiopathic subfoveal CNV is not necessarily associated with a profound loss of vision. Therapies for this type of subfoveal lesion must take into consideration the possibility of a favorable natural course.
Purification and properties of 3-phosphoglyceric acid mutase from caprine erythrocytes

Abstract Relatively simple procedures are described for preparing partially purified phosphoglycerate mutase from erythrocytes of the goat. The kinetic properties of this enzyme are described and compared to those of the same enzyme from human erythrocytes. The Km for 3-phosphoglyceric acid is 6 × 10−4 m . The enzyme has an absolute requirement for 2,3-diphosphoglyceric acid with a Km of 5 × 10−6 m . 2,3-Diphosphoglyceric acid phosphatase activity co-purified with the phosphoglyceric acid mutase. This activity, thought to be an activity of the same enzyme, is greatly stimulated by inorganic pyrophosphate. Its Km for pyrophosphate is 1 × 10−2 m and for 2,3-diphosphoglyceric acid in the phosphatase assay is 1.2 × 10−4 m . No kinetic differences were found between the enzymes of human and caprine origins. The concentration of 2,3-diphosphoglyceric acid in caprine erythrocytes was measured enzymically and found to be 0.03 μmoles per ml cells, approximately 1% of the amount present in the erythrocytes of man. That amount of 2,3-diphosphoglycerate is nevertheless 5-fold above the enzyme's Km value for this cofactor. A second 2,3-diphosphoglyceric acid phosphatase, stimulated by bisulfite, was detected in caprine red cells but its activity was far less than in human erythrocytes.
Regulation of the Matrix Microenvironment for Stem Cell Engineering and Regenerative Medicine

The extracellular matrix (ECM) microenvironment consists of structural and functional molecules. The ECM relays both biochemical and biophysical cues to and from the cells to modulate cell behavior and function. The biophysical cues can be engineered and applied to cells by means of spatial patterning, matrix rigidity, and matrix actuation. Tissue engineering strategies that utilize ECMs to direct stem cell organization and lineage specification show tremendous potential. This review describes the technologies for modulating ECM spatial patterning, matrix rigidity, chemical composition, and matrix actuation. The role of ECMs in vascular tissue engineering is then discussed as a model of tissue engineering and regenerative medicine.
Evaluating truck turn time in grounded operations using simulation

This paper presents in detail techniques for developing simulation models of marine container terminals using Arena. It illustrates the concepts by modelling the Port of Houston's Barbours Cut Container Terminal (BCT) and subsequently discusses how the model can be used to answer one of many operational questions BCT management had ? how many yard cranes are needed to reduce truck turn time to a desirable level. Arena is demonstrated in this research that it can be used to model all aspects of container terminal operations, including the precise movements of trucks and cranes in grounded operations.
Some comments on distributed detection and estimation

In this paper we discuss the question of information and accuracy attainable in distributed processing as compared to central processing. An example is presented where distributed detection suffers zero loss in performance as compared to central detection. In the same example, if the problem considered is one of estimation rather than detection, then it is shown that distributed estimation suffers a loss as compared to central estimation. This shows that the distributed detection and the distributed estimation problems cannot be considered on an equivalent footing. Some comments regarding an accuracy bound in detection problems are also provided. >
Obtaining G-Closures

We pass to methods of description of G m -closures. Recall that a G m -closure is the set of effective properties of all possible composites that are assembled from materials with known properties mixed in certain proportions. The G m -closure problem describes effective properties of all composites that correspond to different microstructures.
The impact of constellation cardinality on Gaussian channel capacity

Denote by C m (snr) the Gaussian channel capacity with signal-to-noise ratio snr and input cardinality m. We show that as m grows, C m (snr) approaches C(snr) = 1 over 2 log(1 + snr) exponentially fast. Lower and upper bounds on the exponent are given as functions of snr. We propose a family of input constellations based on the roots of the Hermite polynomials which achieves exponential convergence.
A BiCMOS active substrate probe card technology for digital testing

An active substrate silicon probe card employs a polyimide membrane formed on a silicon substrate. The probe card combines tungsten probe tips and aluminum interconnects in the polyimide membrane with active test circuitry integrated in the silicon substrate. The card is potentially capable of providing more than 1000 probe tips in an array format. The choice of the active circuitry included in the substrate depends on the application of the probe card. If the probe card is intended for use with conventional digital testers, linear buffers can be integrated into the substrate to isolate the device under test (DUT) outputs from the 50/spl Omega/ transmission lines in the test system and drive those lines from matched impedances. Alternatively, by integrating the front-end circuits of a digital tester into the substrate, timing measurements can be made at distances less than 1cm from the probe tips, resulting in a significant improvement in testing accuracy. In this work, experimental circuits for both approaches are explored. An experimental prototype of an active substrate probe card employing linear buffers is integrated in a 2/spl mu/m BICMOS technology.
DIFFUSION OF STRIP CROPPING IN SOUTHWESTERN WISCONSIN

ABSTRACT Innovation diffusion among farmers is a spatial process involving a large number of independent decisions, whose aggregate indicates the communication patterns and behavioral characteristics of individual decision makers. Contour strip cropping is an innovation which has been widely adopted in southwestern Wisconsin. Its spread is simulated using Hagerstrand's Monte Carlo technique modified to account for the influence of major community centers on communication patterns among farmers. The diffusion process appears to be directed by a decline with distance of neighborhood communication among area farmers within the framework of larger community trade areas.
Abdominal Wall Reconstruction

Patients with abdominal wall reconstruction present a difficult management problem to the oncological surgeon. There were 36 patients treated for abdominal wall primary and secondary tumors between the years 1973 and 1982 at the Memorial Hospital. There were 25 abdominal wall sarcomas, 6 recurrent colon cancers, 2 recurrent bladder cancers, 1 cervical cancer, 1 recurrent endometrial cancer and 3 complications of radiotherapy treated by excision and reconstruction of the defect. The desmoid tumors were closed primarily. The recurrent sarcomas after radical excision, were reconstructed with Marlex mesh and local mobilization of skin and subcutaneous tissue. The recurrent colon bladder and endometrical cancers had been treated with over 5000 cGy each. Three patients had significant full thickness skin loss secondary to radiotherapy. These patients comprised the group that required a myocutaneous flap to provide full thickness skin and fascia. The tensor fascia lata flap was used in eight patients. This group...
Physical and functional coupling of RNA-dependent RNA polymerase and Dicer in the biogenesis of endogenous siRNAs

Physical and functional coupling of RNA-dependent RNA polymerase and Dicer in the biogenesis of endogenous siRNAs
Systemic and Coronary Haemodynamics and Pharmacodynamics of Enalapril and Enalaprilat in Congestive Heart Failure

Enalapril is an effective angiotensin-converting enzyme (ACE) inhibitor which produces salutary, beneficial haemodynamic effects in patients with congestive heart failure. Enalapril also produces beneficial neurohumoral changes, as well as improving abnormal coronary haemodynamics and myocardial energetics that are frequently encountered in these patients. Administration of enalapril once or twice daily appears to be quite effective during maintenance therapy in patients with chronic congestive heart failure.
Cometary magnetospheres: a tutorial

Abstract The nucleus of an active comet, such as comet Halley near its perihelion, produces large quantities of gas and dust. The resulting cometary atmosphere, or coma, extends more than a million kilometers into space, where it interacts with the solar wind. An “induced” cometary magnetosphere is a consequence of this interaction. Cometary ion pick-up and mass loading of the solar wind starts to take place at very large cometocentric distances. Eventually this mass loading leads to the formation of a weak cometary bow shock. Even closer to the nucleus, collisional processes, such as ion-neutral chemistry, become important. Other features of the magnetosphere of an active comet include a magnetic barrier, a magnetotail, and a diamagnetic cavity near the nucleus. X-ray emission from comets is produced by the interaction of the solar wind with cometary neutrals and this topic is also discussed. A broad review of the cometary magnetosphere will be given in this paper.
Arranging frequency dependent data on sequential memories

Often the arrangement of frequency dependent data such as pages on a sequential memory such as disks or tapes critically affects the turnaround time of real-time or dedicated mode processes. Since the size of typical problems renders exact solution techniques impractical, a fast, efficient heuristic procedure becomes very useful. This paper describes such a procedure which is applicable to a general class of objective functions corresponding to seek time functions constrained to be only monotonically piecewise linear.
Static Hand Gesture Recognition based on Local Orientation Histogram Feature Distribution Model

This paper proposes a bottom up approach for static hand gesture recognition. By extending the local orientation histogram feature, we make it applicable to the human hand, an object of very little texture. The key steps are augmenting the local orientation histogram feature vector with its relative image coordinates, and clustering the augmented vector to find a compact yet descriptive representation of the hand shape. The recognition result is given by collective voting of all the local orientation histogram features extracted from the hand region of the testing image. The matching score is evaluated by retrieval in the image feature database of the training hand gestures. Locality sensitive hashing is used to reduce the computational cost for retrieval. The experimental results on labelled real-world images demonstrate superior accuracy and efficiency of our algorithm.
Ghosts of paradigms past: the once and future evolution of psychoanalytic thought.

An example of the psychoanalytic mode of thought is put forward concerning how psychoanalytic theories have historically been constituted and transformed. The model of world hypotheses, characterized by multiple irresolvable truth claims, captures the nature of most psychoanalytic theorizing until about 1970. Each of two world hypotheses—one grounded in intrapsychic conflict (seen when the analyst observes from outside the transference) and the other in interpersonal internalization (seen when the analyst observes from inside the bidirectional interactive processes)—is an autonomous and self-sufficient aggregate. The stance taken by the analyst-observer with respect to the analytic interaction is key to seeing how the two world hypotheses are made manifest in clinical work and in theory. By contrast, the model of competing programs captures the essential nature of most psychoanalytic theorizing since about 1970, and is characterized by the necessity of each progressively evolving through a particular kind...