cssi/SciSciGPT-SciSciNet huggingface dataset:
Nitrogen Fertilizer Suppresses Mineralization of Soil Organic Matter in Maize Agroecosystems

The possibility that N fertilizer increases soil organic matter (SOM) mineralization and, as a result, reduces SOM stocks has led to a great debate about the long-term sustainability of maize-based agroecosystems as well as the best method to estimate fertilizer N use efficiency (FNUE). Much of this debate is because synthetic N fertilizer can positively or negatively affect SOM mineralization via several direct and indirect pathways. Here, we test a series of hypotheses to determine the direction, magnitude, and mechanism of N fertilizer effect on SOM mineralization and discuss the implications for methods to estimate FNUE. We measured the effect of synthetic N fertilizer on SOM mineralization via gross ammonification at two long-term experiments in central and southern Iowa, USA with replicated plots of continuous maize that received one of three ‘historical’ N fertilizer rates (zero, moderate or high) from 1999-2014. In 2015, prior to our measurements, we split the historical N fertilizer rate plots into two subplots that received either the site-specific agronomic optimum N rate or zero N fertilizer. At the onset of rapid maize N uptake, N fertilizer reduced gross ammonification by 13-21% (2-5 kg NH4-N ha-1 d-1). A companion laboratory experiment rejected the hypothesis that differences in net primary productivity between fertilized and unfertilized treatments explained the negative effect of N fertilizer on SOM mineralization. Moreover, the NH4+ pool size was negatively correlated with the gross ammonification rate (r2 = 0.85, p < 0.001). Thus, we conclude that NH4+-N fertilizer had a direct suppressive effect on SOM mineralization. These results demonstrate that the direct effect of N fertilizer on microbial activity can exceed the indirect effects of N fertilizer via large changes in NPP that alter organic matter inputs, soil temperature and moisture content. The magnitude of this effect and specificity to NH4+-N has significant implications for fertilizer management as well as the measurement and modeling of agroecosystem N dynamics including FNUE.
Momentum and Inferential Strategies: How Rational are R&D Investment Decisions?

This study uses longitudinal data on Spanish manufacturing firms between 1998 and 2012 to provide a microfoundational account of R&D investment decisions. While there is evidence for both momentum ...
Considerations of Virtual Peer Leadership Mentoring

This issue of Mentoring and Tutoring: Partnership in Learning Journal includes research from scholars representing Massachusetts, Minnesota, North Dakota, and Texas in the United States, Calgary an...
A retrospective comparison of waterbirth outcomes in two United States hospital settings

Background Water immersion during labor is an effective comfort measure; however, outcomes for waterbirth in the hospital setting have not been well documented. Our objective was to report the outcomes from two nurse-midwifery services that provide waterbirth within a tertiary care hospital setting in the United States. Methods This study is a retrospective, observational, matched comparison design. Data were collected from two large midwifery practices in tertiary care centers using information recorded at the time of birth for quality assurance purposes. Land birth cases were excluded if events would have precluded them from waterbirth (epidural, meconium stained fluid, chorioamnionitis, estimated gestational age 40). Neonatal outcomes included Apgar score and admission to the neonatal intensive care unit. Maternal outcomes included perineal lacerations and postpartum hemorrhage. Results A total of 397 waterbirths and 2025 land births were included in the analysis. There were no differences in outcomes between waterbirth and land birth for Apgar scores or neonatal intensive care admissions (1.8% vs 2.5%). Women in the waterbirth group were less likely to sustain a first- or second-degree laceration. Postpartum hemorrhage rates were similar for both groups. Similar results were obtained using a land birth subset matched on insurance, hospital location, and parity using propensity scores. Discussion In this study, waterbirth was not associated with increased risk to neonates, extensive perineal lacerations, or postpartum hemorrhage. Fewer women in the waterbirth group sustained first- or second-degree lacerations requiring sutures.
Causation vs. Causal Explanation: Which Is More Fundamental?

This essay examines the relation between causation and causal explanation. It distinguishes two prominent roles that causes play within the sciences. On the one hand, causes may work as metaphysical posits. From this standpoint, mainstream in contemporary philosophy, causation provides the ‘raw material’ for explanation. On the other hand, causes may be conceived as explanatory postulates, theoretical hypotheses lacking any substantial ontological commitment. This unduly neglected distinction provides the conceptual resources to revisit longstanding philosophical issues, such as overdetermination and causal pluralism. It also inspires a provocative reframing of Russell’s famous, if notoriously elusive, remarks on the nature of causation.
The tritium burn-fraction in DT fusion

The fraction of the tritium that is burned during one pass through a DT fusion system, $f_{tb}$, is a central issue for success of fusion energy. Reducing the tritium fraction, $f_t$, in a $DT$ burning plasma below a half increases the burn fraction, $f_{tb}\propto1/f_t$ but also the required confinement to achieve a burn $nT\tau_E\propto1/f_t(1-f_t)$. A doubling of the fractional burn entails only a 4/3 enhancement of the required $nT\tau_E$. The energy confinement time $\tau_E$ in tokamaks and stellarators is empirically gyro-Bohm with an approximate factor of two between the best and worse results used to construct scaling laws. Gyro-Bohm is also the approximate level of transport needed in a power plant. What has received little study are $\tau_t/\tau_E$, the ratio of the tritium to the energy confinement time, and $\tau_\alpha/\tau_E$, the ratio of the alpha particle to the energy confinement time. The tritium burn fraction is proportional to $\tau_t/\tau_E$, so the larger the better. The contamination of the plasma by helium ash is proportional to $\tau_\alpha/\tau_E$, so the smaller the better.
Nanodiamond Colloids heat transfer behavior in electronics thermal management – an experimental study

This article reports the heat transfer data obtained from experimenting a novel functionalized nanodiamond (fND) colloid. In this functionalization technique, the nanodiamonds are coupled with mole...
Reduction of vibrations of passively-isolated ultra-precision manufacturing machines using mode coupling

Abstract Ultra-precision manufacturing (UPM) machines are used to fabricate and measure complex parts having micrometer-level features and nanometer-level tolerances/surface finishes. Therefore, random vibration of the machine due to ground excitations and residual vibration stemming from onboard disturbances must be mitigated using vibration isolation systems. A long-standing rule of thumb in vibration isolation system design is to locate the isolators in such a way that the vibration modes of the isolated machine are decoupled. However, prior work by the authors has demonstrated that coupling vibration modes of passively-isolated UPM machines could provide conditions for drastic reduction of residual vibrations compared to decoupling. The authors’ analysis was based on the restrictive assumption that the isolated machine was modally damped. The key contribution of this paper is in investigating the effect of mode coupling on the residual vibrations of UPM machines with non-proportional (NP) damping—which is more realistic than modal damping. It also analyzes the effects of mode coupling on the reduction of ground vibrations (i.e., transmissibility). The analyses reveal that, even though NP damping changes the vibration behavior of the machine compared to modal damping, mode coupling still provides ample opportunities to reduce residual vibration and transmissibility. Guidelines for properly designing a UPM machine to best exploit mode coupling for vibration reduction are provided and validated through simulations and experiments. Up to 40% reduction in residual vibration and 50% reduction in transmissibility are demonstrated.
Immune Deviation of the Allergic Response by DNA Immunization

Publisher Summary Gene vaccination has been successfully utilized to elicit antitumour, antiidiotype, and allo-immune responses, to suppress an auto-immune disease (experimental allergic encephalitis) as well as to inhibit allergic responses. intramuscular (i.m.) gene vaccination is effective in generating humoral and cellular immune responses to the gene product (antigen), the skin and mucous membranes are the anatomical sites where most exogenous antigens are normally encountered. The skin-associated lymphoid tissue contains specialized cells that enhance immune responses. The keratinocytes produce IL-1, TNF-α and IL-12, which can activate lymphocytes, and antigen-presenting cells (APCs) such as macrophages, dendritic cells (DCs) and Langerhans' cells (LCs). The APCs carry the antigen from the skin to the draining lymph nodes where they activate naive T lymphocytes. In gene-vaccinated animals, bone marrow-derived cells (e.g. APCs) and not somatic cells (e.g. keratinocytes or myocytes) dictate the nature of the subsequent immune response to the encoded antigen. Therefore, the in vivo transfection of dermal and epidermal cells, and especially APCs, would be expected to provide an efficient route for gene immunization that mimics the physiological response to viral infections of the skin.
A Visual Hardware Description Language

Abstract One difficulty in using conventional hardware description languages such as VHDL is the cumbersome nature of the textual syntax. We are developing a visual hardware description language, called vVHDL, based on VHDL. A visual approach is very natural for expressing the concurrency inherent in hardware designs. vVHDL allows the graphical specification of both structure and behavior of hardware components in a uniform framework. This paper presents an overview of the vVHDL language and design system.
Accurate Modeling of Nonlinear Systems using Volterra Series Submodels

We investigate the problem of accurately modeling nonlinear systems (such as aircraft flight in high angle-of-attack/sideslip flight) using simple low-order Volterra submodels. First, we apply this technique to a simplified nonlinear stall/post-stall aircraft model for the case of a longitudinal limit cycle. Our simulation study demonstrates that the responses of the Volterra submodels accurately match the responses of the original nonlinear model, whereas the responses of a piecewise-linear model do not. Next, we apply the technique to a simplified high a nonlinear model of wing rock. Our simulation study demonstrates that the second-order Volterra approximation predicts the wing rock limit cycle, while a linear approximation does not. Third-, fourth- and fifth-order Volterra approximations are observed to give wing rock amplitudes that converge quadratically to the nonlinear value.
What Happens to CEOs After They Retire? New Evidence on Career Concerns, Horizon Problems, and CEO Incentives

This paper provides evidence on a previously unidentified source of managerial incentives: concerns about post-retirement board service. Both the likelihood that a retired CEO serves on his own board two years after departure, as well as the likelihood of serving as an outside director on other boards, are positively and strongly related to his performance while CEO. Retention on the CEO's own board depends primarily on stock returns, while service on outside boards is better explained by accounting returns. The evidence also suggests that firms consider ability in choosing board members.
Bacteriological and Pathological Study of Animals Given Freund Adjuvant

Abstract Freund complete adjuvant, with allegedly „killed and dried” Mycobacterium butyricum added (intramuscularly in rabbits and intraperitoneally in mice), produced a local granulomatous lesion and frequently a similar lesion in the viscera. Acid-fast bacilli were present in these lesions, and in some animals M. butyricum was obtained in culture. When this culture was inoculated in mice, a similar lesion developed. Pathological lesions with similar acid-fast organisms also were observed by us in rabbits given Freund complete adjuvant by two other investigators.
Numerical Simulation of Anisotropic Shrinkage in a 2D Compact of Elongated Particles

Microstructural evolution during simple solid-state sintering of two-dimensional compacts of elongated particles packed in different arrangements was simulated using a kinetic, Monte Carlo model. The model used simulates curvature-driven grain growth, pore migration by surface diffusion, vacancy formation, diffusion along grain boundaries, and annihilation. Only the shape of the particles was anisotropic; all other extensive thermodynamic and kinetic properties such as surface energies and diffusivities were isotropic. We verified our model by simulating sintering in the analytically tractable cases of simple-packed and close-packed, elongated particles and comparing the shrinkage rate anisotropies with those predicted analytically. Once our model was verified, we used it to simulate sintering in a powder compact of aligned, elongated particles of arbitrary size and shape to gain an understanding of differential shrinkage. Anisotropic shrinkage occurred in all compacts with aligned, elongated particles. However, the direction of higher shrinkage was in some cases along the direction of elongation and in other cases in the perpendicular direction, depending on the details of the powder compact. In compacts of simple-packed, mono-sized, elongated particles, shrinkage was higher in the direction of elongation. In compacts of close-packed, mono-sized, elongated particles and of elongated particles with a size and shape distribution, the shrinkage was lower in the direction of elongation. The results of these simulations are analyzed, and the implication of these results is discussed.
The Standard Model, Dark Matter, and Dark Energy: From the Sublime to the Ridiculous

The Standard Model of cosmology of the 1980's was based on a remarkable interplay of ideas from particle theory, experiment and astrophysical observations. That model is now dead, and has been replaced by something far more bizarre. Interestingly, the aspect that has survived involves perhaps the most exotic component: dark matter that dominates the gravitational dynamics of all galaxies, and appears to be composed of a sea of new weakly interacting elementary particles. But this sea of dark matter appears to play second fiddle to an unknown energy density that appears to permeate all of space, causing the expansion of the Universe to accelerate. We are left with many more questions than answers, and our vision of the future of the Universe has completely changed. (Lectures Given at the XIV Canary Islands Winter School in Astrophysics 2002: Dark Matter and Dark Energy in the Universe. Nov 2002 To Appear in the Proceedings)
Orthogonal Mixing and CP Violation

In this talk I discuss (I) the history of CP, (II) the aspon model, (III) production of A and Q in pp collisions at LHC (IV) B decay (V) Cabibbo mixing and finally (VI) summarize.
Sterculic oil, a natural inhibitor of SCD1, improves the metabolic state of obese OLETF rats.

Objective: Abnormal lipid metabolism and excess accumulation of lipid in non-adipose tissues are defining characteristics of obesity and its comorbidities. Expression and/or activity of stearoyl-CoA desaturase-1 (SCD1), a major regulator of lipid metabolism, is increased with obesity and the reduction/ablation of this enzyme is associated with an improved metabolic profile. Sterculic oil (SO), obtained from the seeds of the Sterculia feotida tree, contains a high concentration of cyclopropenoic fatty acids which are known inhibitors of SCD1. The purpose of this study was to determine the effects of SO supplementation on the development of obesity and insulin resistance in hyperphagic, obese Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Design & Methods: Rats received either an AIN-93G diet (control) or an AIN-93G diet containing 0.5% SO for 10 weeks. Results: SO did not alter body weight or body composition. Importantly, the desaturase indices, a proxy for the activity of SCD1, were reduced in the liver and adipose tissue of SO supplemented animals. This reduction in SCD1 activity was associated with a reduction in fasting blood glucose concentrations and improved glucose tolerance. In addition, SO reduced intra-abdominal fat mass and adipocyte size and resulted in a ∼3-fold increase in GLUT1 gene expression in intra-abdominal fat. Liver triglyceride content and lipogenic gene expression were reduced by SO. Consistent with an improved metabolic phenotype, SO also improved plasma cholesterol, LDL-cholesterol, and triglyceride concentrations. Conclusion: Overall, our data demonstrate an improved metabolic phenotype with SO supplementation and suggest further studies are required to better understand the therapeutic potential of SO.
Inhibition of glycogen synthesis in rat hepatocytes by medium Zn2

In hepatocytes from fasted rats, Zn2+ in the range from 0 to 500 microM has relatively minor effects on gluconeogenesis from most substrates, or on ureagenesis from NH3. In hepatocytes from fed rats, Zn2+ does not affect glycogenolysis. In hepatocytes from fasted rats, in which glycogen is being actively synthesized using the substrate combination (Katz et al. (1976) Proc. Natl.Acad.Sci.USA 73,3433-3437) of glucose, lactate and glutamine (all 10mM), Zn2+ markedly inhibits glycogen synthesis, with total inhibition at 500 microM, and a half maximal effect in the range from 50 to 100 microM. Dipicolinate (pyridine 2,6-dicarboxylate), a zinc chelator, is about as effective as L-glutamine in activating glycogen synthesis with the substrate combination of dihydroxyacetone, lactate and glucose (all 10mM). This suggests the possible hypothesis that endogenous Zn2+ might control the rate of glycogen synthesis in vivo. However, alternate explanations such as metabolite accumulation are also possible, since dipicolinate causes inhibition of gluconeogenesis from L-lactate.
Apoptosis-mediated medullary thyroid cancer growth suppression by the PI3K inhibitor LY294002.

Background Medullary thyroid cancer (MTC) cells exhibit frequent activation of the PI3K pathway as evidenced by the presence of hyperactivation of Akt kinases and overexpression of neuroendocrine (NE) markers. We hypothesized that the inhibition of the PI3K pathway in MTC may lead to a reduction in cell growth and NE tumor marker production. Methods Human MTC-TT cells were treated with the PI3K inhibitor LY294002 (0-60 μmol/L) for 8 days, and cellular growth was measured. Further, TT cells were treated with nontoxic concentrations of LY294002 for 2 days, and Western blot analyses were performed for phospho-Akt, total Akt, and the NE tumor markers CgA and human achaete-scute homolog1 (ASCL1). Results Treatment of TT cells with LY294002 significantly suppressed levels of phospho-Akt. Notably, a dose-dependent reduction in cellular proliferation was also observed. Importantly, NE marker production was also reduced. Mechanistically, we show that cell growth inhibition by PI3K inactivation is mediated by apoptosis attributable to an increase in the levels of cleaved poly(ADP-ribose) polymerase and caspase-3. Conclusions MTC cell growth and NE marker production appear to depend on activation of the PI3K-signaling cascade. Inhibition of this important signal transduction pathway may lead to a possible therapeutic strategy to treat patients with MTC.
Hackerspaces and the Internet of Things in China: How makers are reinventing industrial production, innovation, and the self:

This article discusses the visions and practices of DIY (do-it-yourself) maker culture in China. It analyses how the ideals held by DIY makers, such as openness, peer production, and individual empowerment, are formulated in relation to China’s project of building a creative society and economy. To demonstrate, this article draws from long-term ethnographic research, including the setting up of China’s first hackerspace, the proliferation of making, and partnerships between makers and manufacturers. China’s makers are driven to reinvent what creativity, innovation, industrial production and citizenship mean today, simultaneously exploiting and challenging political rhetoric. By setting up hackerspaces, designing open technologies and starting up businesses, they craft alternative subject positions, for themselves and others. The contribution of this article is threefold. First, it fills a gap in current research by providing an account of a culture of technology production. Second, it proposes the analyti...
Length Dependence of Cardiac Myofilament Ca2+ Sensitivity in the Presence of Substitute Nucleoside Triphosphates

Abstract Although ATP is the immediate source of energy for muscle contraction other nucleoside triphosphates (NTP) can substitute for ATP as substrates for myosin and as sources of energy for contraction of skinned muscle fibers. However, experiments with skinned skeletal muscle fibers in the presence of substitute NTP indicate significant differences with respect to cross-bridge kinetics, force generation, and Ca 2+ regulation. In this study the length dependence of Ca 2+ sensitivity of skinned bovine cardiac muscle was analyzed in the presence of MgATP, MgCTP, MgUTP, and MgITP. Ca 2+ regulation in the presence of MgCTP and MgUTP was essentially the same as in the presence of MgATP, although the maximum force generated (at sarcomere length 2.4 μ m) was about 25% less. However, the length dependence of Ca 2+ sensitivity was eliminated in the presence of MgUTP. With MgITP the maximum force generated (at sarcomere length 2.4 μ m) was about the same as in the presence of MgATP, but there was an impairment of relaxation such that at pCa 8 the force developed was about 50–60% of that developed at pCa 5. Moreover, the Ca 2+ -dependent component showed no length-dependent sensitivity. Thus length modulation of Ca 2+ sensitivity is a function of the myosin substrate. Taken in conjunction with other data, the results are consistent with the hypothesis that length-dependence of Ca 2+ sensitivity is modulated at a step upstream from the force-generating reaction.
Maximum Velocity as an Index of Contractility in Cardiac Muscle: A CRITICAL EVALUATION

The use of maximum velocity of shortening (V max ) as an index of contractility has been based on the assumption that V max of muscle fibers is equivalent to V max of the contractile element. It is shown here that such equivalence applies to the two-element model of skeletal muscle but not to three-element models of cardiac muscle. Analysis of published data in terms of the Voigt and Maxwell three-element models shows that the V max of the contractile element, unlike that of the muscle fibers, is not independent of fiber length but increases at least 50% for a 25% increase of fiber length. Moreover, V max of the contractile element is seen to be even more highly dependent on fiber length when correction is made for the nonuniform contribution of levels of active state to the force-velocity curves giving rise to V max of the contractile element. It appears that in cardiac muscle an inotropic shift of V max of the contractile element cannot be distinguished from a shift due to change in fiber length, thus invalidating it as an index of contractility.
Enduring social and behavioral effects of exposure to military combat in vietnam

PURPOSE: To assess current social and behavioral outcomes among Vietnam veterans up to 35 years after exposure to military combat.METHODS: A cohort of 1,315 American Legion members whose combat experiences were assessed with a standard quantitative measure in 1984 were followed-up through 1998 for current health and psychosocial status. Another 2,260 Legionnaires who served outside Vietnam during the same period were used as a comparison group. Outcomes included smoking and drinking habits as health risk indicators, income, measures of marital and general happiness and life satisfaction, and the Columbia Univerity PERI (Psychiatric Epidemiology Research Instrument) scales for psychological well-being: anxiety, depression, helplessness/hopelessness, anger and irritation, and physical symptoms of depression. Combat intensity was classified as high, medium, and low.RESULTS: Income was significantly lower in the high-combat group by $4,000 per year compared to the low- and medium-combat groups and the non-Southeast Asia veterans, whose incomes were similar to each other. Marital happiness, life happiness, general life satisfaction, decreased with increasing combat, while smoking prevalence increased with combat score. The PERI scale components were strongly dose-related to combat intensity. Furthermore, the anger/irritation score for the low-combat group was significantly higher than for the non-SEA group.CONCLUSIONS: Although practically all veterans in this study last saw combat prior to 1971, the detrimental effects of having experienced combat which were strongly apparent when this group was surveyed in the 1980s continue to exert an adverse effect on many aspects of their lives almost three decades after the war.
Jet-A fuel evaporation analysis in conical tube injectors

A simple one-dimensional drop-life-history analysis and a multidimensional spray calculation using KIVA-II code are applied to the vaporization of Jet-A fuel in multiple tube injectors. Within the assumptions of the analysis, the one-dimensional results are useful for design purposes. The pressure-atomizer breakup models do not accurately predict the dropsize measured experimentally or deduced from the one-dimensional analysis. Cold flow visualization and dropsize measurements show that capillary wave breakup mechanism plays an important role in the spray angle and droplet impingement on the tube wall.
Factor IX concentrate therapy and thrombosis: relation to changes in plasma antithrombin III

Commercial factor IX (fIX) concentrate therapy has been associated with thrombogenic complications, the cause of which is uncertain. We have previously reported that infusion of these fIX concentrates led to a decrease in antithrombin III (ATIII) functional activity, but not antigen, from pre-infusion levels. The patient plasmas also showed a cathodal shift in ATIII antigen by crossed immunoelectrophoresis (CIEP). We chose to characterize these ATIII changes more extensively in additional patients, by functional assays, radial immunodiffusion (RID), and CIEP. The effects of commercial fIX concentrate therapy on plasma ATIII levels appear to be dose-related, with most pronounced effects at 100 U/Kg; the effects are also cumulative, with a persistence of ATIII changes 24 hours after infusion in patients on daily therapy. We also studied pre- and post-infusion ATIII levels in patients who received 100 U/Kg of a more purified fIX concentrate (American Red Cross), which contains little or no activated clotting factors and has been shown to be non-thrombogenic in animal models. These patients showed no change post-infusion in ATIII levels by clotting, amidolytic, or RID assays, nor any significant change by CIEP. These data suggest that the ATIII changes that occur predictably after commercial fIX concentrate therapy are caused by a contaminating protein or proteins other than fIX and that the ATIII changes observed are related to the thrombotic complications of these commercial concentrates.
Simulation of the drain-current characteristics of MOSFETs with ultrathin oxides in the presence of direct tunneling

Carrier tunneling in the gate dielectric, especially in the direct-tunneling regime where large current densities flow through the gate oxide, are known to result in substantial changes in the drain-current characteristics of MOSFETs. In this paper, we present simulation results of the drain-current characteristics of MOSFETs with ultrathin oxide using Tunnel-PISCES, a MOSFET tunneling simulator that models electron tunneling through the gate dielectric in a self-consistent manner with carrier transport by drift and diffusion in the substrate. We are able to predict the experimental trends reported for the dependence of the drain current of ultrathin-oxide MOSFETs on gate-oxide thickness. This tunneling simulation capability provides a means for generating MOSFET sizing guidelines to avoid tunneling-induced drain-current degradation.
Effects of partial left ventriculectomy on left ventricular performance in patients with nonischemic dilated cardiomyopathy

Abstract Objectives. This study sought to assess the effects of partial left ventriculectomy (PLV) on left ventricular (LV) performance in a series of consecutive patients with nonischemic dilated cardiomyopathy. Background. Reduction of LV systolic function in patients with heart failure is associated with an increase of LV volume and alteration of its shape. Recently, PLV, a novel surgical procedure, was proposed as a treatment option to alter this process in patients with dilated cardiomyopathy. Methods. We studied 19 patients with severely symptomatic nonischemic dilated cardiomyopathy, before and 13 ± 3 days after surgery, and 12 controls. Single-plane left ventriculography with simultaneous measurements of femoral artery pressure was performed during right heart pacing. Results. The LV end-diastolic and end-systolic volume indexes decreased after PLV (from 169 to 102 ml/m2, and from 127 to 60 ml/m2, respectively, p Conclusions. The PLV improves LV performance by a dramatic reduction of ventricular end-systolic and end-diastolic stresses. Further studies are needed to assess whether this effect is sustained during long-term follow-up and to define the role of PLV in the treatment of patients with dilated cardiomyopathy.
Charge-coupled device camera for the Galileo Jupiter Orbiter spacecraft

A slow-scan television camera called the solid-state imaging subsystem (SSI), built for the Galileo Jupiter Orbiter, is described. The SSI consists of a 1500-mm focal-length telescope coupled to a camera head housing a 800 x 800-element charge-coupled device (CCD) detector based on 'virtual-phase' charge transfer technology. The CCD detector provides broadband sensitivity over 100 times that of a comparable vidicon-tube camera, while also yielding improved resolution, linearity, geometric fidelity, and spectral range. The system noise floor is 30 electrons, which results in a dynamic range of about 3500. Saturation of the detector with 9000-A light, followed by a high-speed erasure cycle prior to exposing each image, stabilizes the detector quantum efficiency at its maximum level for wavelengths beyond 7000 A. An optical schematic diagram of the SSI is included.
SEM/XPS analysis of fractured adhesively bonded graphite fibre-reinforced polyimide composites

The surfaces of the graphite fiber-reinforced polyimide composites presently pretreated prior to bonding with polyimide adhesive contained variable amounts of a fluoropolymer, as determined by X-ray photoelectron spectroscopy. Lap shear strengths were determined for unaged samples and for those aged over 500- and 1000-hour periods at 177 and 232 C. Unaged sample lap strengths, which were the highest obtained, exhibited no variation with surface pretreatment, but a significant decrease is noted with increasing aging temperature. These thermally aged samples, however, had increased surface fluorine concentration, while a minimal concentration was found in unaged samples. SEM demonstrated a progressive shift from cohesive to adhesive failure for elevated temperature-aged composites.
Litterfall and fine root biomass contribution to nutrient dynamics in second- and old-growth Douglas-fir ecosystems

Litterfall and fine root production were measured for three years as part of a carbon balance study of three forest stands in the Pacific Northwest of the United States. A young second-growth Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] stand, a second-growth Douglas-fir with red alder (Alnus rubra Bong.) stand, and an old-growth (∼550 years) Douglas-fir stand were monitored for inputs of carbon and nitrogen into the soil from litterfall and fine root production, as well as changes in soil C and N. Fine root production and soil nutrient changes were measured through the use of soil ingrowth bags containing homogenized soil from the respective stands. Litterfall biomass was greatest in the Douglas-fir-alder stand (527 g m−2 yr−1) that annually returned nearly three times the amount of N as the other stands. Mean residence time for forest floor material was also shortest at this site averaging 4.6 years and 5.5 years for C an N, respectively. Fine root production in the upper 20 cm ranged from 584 g m−2 in the N rich Douglas-fir-alder stand to 836 g m−2 in the old-growth stand. Fine root production (down to one meter) was always greater than litterfall with a below:above ratio ranging from 3.73 for the young Douglas-fir stand to 1.62 for the Douglas-fir-alder stand. The below:above N ratios for all three stands closely approximate those for biomass. Soil changes in both C and N differed by site, but the soil C changes in the old-growth stand mirrored those obtained in an ongoing CO2 flux study. Results from the soil ingrowth bags strongly suggest that this method provides a simple, but sufficient device for measuring potential fine root biomass production as well as soil chemical changes.
Strehl ratio for primary aberrations: some analytical results for circular and annular pupils.

Imaging systems with circular and annular pupils aberrated by primary aberrations are considered. Both classical and balanced (Zernike) aberrations are discussed. Closed-form solutions are derived for the Strehl ratio, except in the case of coma, for which the integral form is used. Numerical results are obtained and compared with Marechal’s formula for small aberrations. It is shown that, as long as the Strehl ratio is greater than 0.6, the Marechal formula gives its value with an error of less than 10%. A discussion of the Rayleigh quarter-wave rule is given, and it is shown that it provides only a qualitative measure of aberration tolerance. Nonoptimally balanced aberrations are also considered, and it is shown that, unless the Strehl ratio is quite high, an optimally balanced aberration does not necessarily give a maximum Strehl ratio.
Neutrophil PRV-1 expression across the chronic myeloproliferative disorders and in secondary or spurious polycythemia.

Recent studies have demonstrated neutrophil overexpression of the polycythemia rubra vera-1 (PRV-1) gene in polycythemia vera (PV) but not in secondary or spurious polycythemia (SP). To validate as well as expand upon this novel observation, we conducted a prospective study of 88 subjects: 30 with PV, 22 with SP, 14 with essential thrombocythemia (ET), 12 with myelofibrosis with myeloid metaplasia (MMM), and 10 controls. To minimize interstudy methodologic differences, we used a published real-time polymerase chain reaction (PCR)-based assay. The proportion of patients with increased neutrophil PRV-1 expression was 83% in PV, 21% in ET, 42% in MMM, 18% in SP, and 0% in controls. All 5 MMM patients with PRV-1 up-regulation had an antecedent history of PV. We conclude that neutrophil PRV-1 up-regulation is a characteristic feature of PV that may not be affected by fibrotic transformation. However, quantifying neutrophil PRV-1 mRNA, while complementary to other tests, is not in itself sufficient for the diagnosis of PV. (Blood. 2004;103:3547-3548)
Potassium graphites prepared by mixed-reaction technique

Abstract The unique lamellar compounds of potassium graphite (KC 8 , KC 24 , KC 36 , KC 48 , and KC 60 ) have been successfully prepared by a simple, mixed-reaction technique. The electrical conductivity of pressed samples of KC 8 , KC 24 , KC 36 , KC 60 , and graphite were measured as a function of temperature from 90 to 350°K, and compared with data on well-oriented crystals.
MALDI tissue imaging: from biomarker discovery to clinical applications

Matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) is a powerful tool for the generation of multidimensional spatial expression maps of biomolecules directly from a tissue section. From a clinical proteomics perspective, this method correlates molecular detail to histopathological changes found in patient-derived tissues, enhancing the ability to identify candidates for disease biomarkers. The unbiased analysis and spatial mapping of a variety of molecules directly from clinical tissue sections can be achieved through this method. Conversely, targeted IMS, by the incorporation of laser-reactive molecular tags onto antibodies, aptamers, and other affinity molecules, enables analysis of specific molecules or a class of molecules. In addition to exploring tissue during biomarker discovery, the integration of MALDI-IMS methods into existing clinical pathology laboratory practices could prove beneficial to diagnostics. Querying tissue for the expression of specific biomarkers in a biopsy is a critical component in clinical decision-making and such markers are a major goal of translational research. An important challenge in cancer diagnostics will be to assay multiple parameters in a single slide when tissue quantities are limited. The development of multiplexed assays that maximize the yield of information from a small biopsy will help meet a critical challenge to current biomarker research. This review focuses on the use of MALDI-IMS in biomarker discovery and its potential as a clinical diagnostic tool with specific reference to our application of this technology to prostate cancer.
Passage of thyroid hormone across the placenta in intact and hypophysectomized rats.

The studies were designed to determine whether thyroid hormone traverses the placenta of the rat. 1. Pregnant rats were hypophysectomized on the twelfth day of the gestation period. The histological appearance and wet weights of the fetal thyroids at term were determined and found to be the same as that of fetuses of intact mothers. These results indicate that maternal TSH is not required for maturation of the fetal thyroid. 2. Intact and hypophysectomized pregnant rats were provided with a diet supplemented with 0.2% propylthiouracil (PTU) added in powdered form starting on the fifteenth day of gestation until term. This treatment led to enlargement of thyroids of fetuses of intact and hypophysectomized mothers. 3. Groups of intact and hypophysectomized pregnant rats given the same goitrogenic treatment as group 2 were injected daily with 100, 50, 25 and 12.5 μg of 1-thyroxin in suspension. Twenty-five μg of thyroxin were sufficient to inhibit goiter development in fetuses of hypophysectomized rats, while 50 μg was required to prevent the goiter formation in fetuses obtained from intact non-hypophysectomized pregnant rats. These results suggest that maternal thyroid hormone passes the placenta from mother to fetus. The effectiveness with which thyroid hormone passes from the mother to the fetal circulation is probably influenced in some way by the maternal pituitary.
DEVELOPMENT OF A RELIABILITY-BASED ALTERNATIVE TO API RP2A

Since 1980, API has been developing the new load resistance factored design (LRFD) method for fixed offshore platform design. In contrast with the currently used API RP2A working stress design (WSD) method in the LRFD method, platform loads and component strengths are modified by factors representing their statistical uncertainties. This results in a more uniform safety (reliability) for a wide range of load and load combinations and component types. This paper summarises the LRFD method development efforts sponsored by API since 1980. Results from 16 API research projects performed to formulate the LRFD method and calibrate it against 6 fixed platforms in different water depths, locations and environments are outlined. Advantages of the LRFD method against the current API working stress design (WSD) method are also discussed.
Mechanism of the vulnerable period in a model of cardiac fibrillation

Vulnerable Period. The mechanism of the vulnerable period for induction of fibrillation was investigated with a computer model of propagated excitation. The model included nonuniform cycle length dependent refractoriness and slow propagation during incomplete recovery. Recovery properties that permitted induction of fibrillation by a single stimulus were identified, and fibrillation usually occurred after stimuli later than the earliest stimulus resulting in propagation. The responsible mechanism was slow propagation near the stimulus site during excitation from the earliest effective stimulus. The time required for That propagation permitted sufficient recovery in surrounding regions that excitation propagated without reentry. Later stimulation was associated with more rapid propagation near The stimulus site, so surrounding regions were invaded while recovery was markedly nonuniform. This resulted in nonuniform propagation and self sustained reentrant excitation simulating fibrillation. Nonuniformity of premature propagation was quantitated and increased with increasing stimulus cycle length before progressively decreasing. The time of maximal increase of nonuniformity became later with increasing mean value of disparate recovery, but was not affected by The range of disparity. Findings provide a possible explanation for failure of The earliest propagated premature response to initiate fibrillation and suggest That prolonged recovery is associated with vulnerability to late premature responses. (J Cardiovasc Electrophysiol, Vol. l, pp. 303–308, June 1990)
Correlation of AO and Lauge-Hansen classification systems for ankle fractures to the mechanism of injury.

Background:Our aim was to assess whether the Lauge-Hansen (LH) and the Muller AO classification systems for ankle fractures radiographically correlate with in vivo injuries based on observed mechanism of injury.Methods:Videos of potential study candidates were reviewed on YouTube.com. Individuals were recruited for participation if the video could be classified by injury mechanism with a high likelihood of sustaining an ankle fracture. Corresponding injury radiographs were obtained. Injury mechanism was classified using the LH system as supination/external rotation (SER), supination/adduction (SAD), pronation/external rotation (PER), or pronation/abduction (PAB). Corresponding radiographs were classified by the LH system and the AO system.Results:Thirty injury videos with their corresponding radiographs were collected. Of the video clips reviewed, 16 had SAD mechanisms and 14 had PER mechanisms. There were 26 ankle fractures, 3 nonfractures, and 1 subtalar dislocation. Twelve fractures with SAD mechanisms...
Proton Conductivity in Sulfonic Acid-Functionalized Zeolite Beta: Effect of Hydroxyl Group

Sulfonic acid groups are more important than framework aluminum for fast proton transport in zeolite beta, but the presence of dangling hydroxyls is also advantageous for high proton conductivity.
Microelectromechanical system-based vacuum gauge for measuring pressure and outgassing rates in miniaturized vacuum microelectronic devices

Cr/Au meander-shaped resistors were fabricated on 0.2 μm thick square-shaped silicon nitride diaphragms with diaphragm dimensions ranging from 0.775 to 2.275 mm. The performance of these sensors was measured in a vacuum chamber as a function of resistor powers from 0.5 to 3 mW at pressures ranging from 2×10−4 to 760 Torr. The lengths of the meander-shaped resistors increase from 5.5 mm for the 0.775 mm diaphragm to 33.6 mm for the 2.275 mm diaphragm devices. It is shown that the pressure dependence of the devices is governed by the kinetic gas theory and that the devices can measure pressures from about 10 to 1×10−3 Torr. At a resistor power of 2 mW at 760 Torr, the 2.275 mm diaphragm device, which has the largest sensing area, exhibits the highest sensitivity.
Migration of a Kirschner wire from the clavicle into the pulmonary artery

Abstract A case of migration of a Kirschner wire from the right clavicle into the right pulmonary artery is presented. The lethal potential of migrating orthopedic metallic fixation devices is evident. Frequent postoperative radiographic examinations should be made. If migration of the device occurs, early removal seems indicated.
Dysphagia teams: A specific approach to a non-specific problem

Dysphagia is a widespread problem among patients in both acute and chronic care facilities. Once the etiology of the dysphagia is diagnosed, the patient frequently must cope with chronic, functional swallowing problems. This article describes teams developed in acute care settings that are composed of members of disciplines directly involved with these functional problems. Members of one team had no specific expertise in dysphagia prior to joining the team. The teams received clinical and administrative support at two facilities. The authors believe this approach to care can be utilized by others in a cost-effective manner to alleviate malnutrition and aspiration, as well as to support staff members and patients as they cope with often chronic functional disabilities. Descriptions of team patients are provided, based on retrospective reviews of team consultations and clinical records.
Demonstration of 2,3,7,8-tetrachlorodibenzo-p-dioxin attenuation of P450 steroidogenic enzyme mRNAs in rat granulosa cell in vitro by competitive reverse transcriptase-polymerase chain reaction assay

Abstract We investigated the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in prepubertal (PP) and adult (A) rat granulosa cells (GC) in vitro by examining the changes in estrogen secretion, aromatase enzyme activity and mRNAs for steroidogenic enzymes P450scc, 3β-HSDI, P450arom; and for components of the AHR signaling pathway-CYP1A1, aromatic hydrocarbon receptor (AHR), and the AHR nuclear translocator protein (ARNT). In PP and A rat GC, TCDD (3.1 nM) reduced estrogen secretion at 48 h without altering aromatase enzyme activity. Addition of FSH (50 ng/ml) increased aromatase activity in GC with or without TCDD. FSH-induced aromatase activity was significantly reduced by TCDD (3.1 nM) at 48 h. Semi-quantitative RT-PCR showed a significant increase in CYP1A1 mRNA both at 24 and 48 h with TCAP, while a significant reduction in P450scc and P450arom mRNA was observed with competitive RT-PCR. All steroidogenic enzyme mRNAs were significantly lower in adults than in PP GC. We conclude that in rat GC, TCDD modulates the level of cytochrome P450 enzymes involved in the steroid biosynthetic cascade. This effect may be attributable to AHR interaction with dioxin-responsive elements present in the genes encoding these enzymes.