cssi/SciSciGPT-SciSciNet huggingface dataset:
Technologies for Aircraft Noise Reduction

Technologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise reduction benefits for communities surrounding airports. Historical progress in noise reduction and technologies available for future aircraft/engine development are identified. Technologies address aircraft/engine components including fans, exhaust nozzles, landing gear, and flap systems. New "chevron" nozzles have been developed and implemented on several aircraft in production today that provide significant jet noise reduction. New engines using Ultra-High Bypass (UHB) ratios are projected to provide about 10 EPNdB (Effective Perceived Noise Level in decibels) engine noise reduction relative to the average fleet that was flying in 1997. Audio files are embedded in the presentation that estimate the sound levels for a 35,000 pound thrust engine for takeoff and approach power conditions. The predictions are based on actual model scale data that was obtained by NASA. Finally, conceptual pictures are shown that look toward future aircraft/propulsion systems that might be used to obtain further noise reduction.
TH-CD-204-07: Evaluation of Dynamic Fractal Signature Dissimilarity as a Novel Biomarker in Therapeutic Response Assessment Using Dynamic Contrast-Enhanced MRI

Purpose: To evaluate dynamic fractal signature dissimilarity (FSD) analysis in the therapeutic response assessment using longitudinal DCE-MRI. Methods: A novel texture analysis method of dynamic FSD was proposed to quantify the heterogeneity of contrast agent (CA) uptake during a DCE-MRI exam. 16 nu/nu mice with LS-174T implanted were randomly assigned into treatment/control groups (n=8/group) and received bevacizumab/saline three times (Day1/Day4/Day8). All mice received one pre-(Day0) and two post-treatment (Day2/Day9) scans. For each scan, pharmacokinetic (PK) analysis was performed using the extended Tofts model, and a dynamic FSD curve was generated using the DCE images in the first two minutes after CA injection. Two heuristic features of a dynamic FSD curve, Area Under Curve (AUCFSD) and Maximum Enhancement (MEFSD), were compared against the tumor volume V and the tumor permeability rate constant Ktrans. For each post-treatment scan, the relative values (in reference to Day0 values) of AUCFSD, MEFSD, V and Ktrans were recorded. The Mann-Whitney U-test was used to assess the differences of the relative values between treatment/control groups. Experiments using support vector machine in a leave-one-out approach were performed to validate the use of relative AUCFSD, ME FSD and Ktrans as biomarkers in treatment/control group classification. Results: At Day2, the relative AUCFSD (p=0.012) and MEFSD (p=0.036) in the treatment group were significantly larger than those in the control group, while no significantly differences were observed for the relative Ktrans (p=0.916) and V (p=0.093). At Day9, significant differences between two groups were observed for the relative AUCFSD (p=0.012), MEFSD (p=0.009) and V (p=0.001) but not for relative trans (p=0.462). The classification accuracy using two post-treatment relative values of AUCFSD, MEFSD and Ktrans was 87.5%, 87.5% and 31.3%, respectively. Conclusion: The proposed dynamic FSD may serve as a reliable DCE-MRI analysis method and is promising for the early assessment of therapeutic response.
Evidence for a Spatiotemporal Singularity in Percept Formation by Cerebral Cortex

Perception proceeds by cinematic frames that are separated by an endogenous shutter, which is intrinsic to the background spontaneous activity of cerebral cortex. Cinematic displays of spatiotemporal electrocorticograms (ECoG) show turbulence, from which stable spatial patterns emerge that are correlated with perception of conditioned stimuli (CS). Extracting invariant properties of the perceptual patterns requires high-resolution measurements by high-density electrode arrays, high-order FIR filters, and the Hilbert transform giving analytic signals (instantaneous amplitudes and frequencies). Each pattern is preceded by a null spike, which is postulated to reveal a singularity in cortical dynamics that operates the shutter. A piecewise linear model is used to solve the nonlinear differential equations of mesoscopic cortical dynamics. Solutions point to the existence of a limit cycle attractor. The behavioral and physiological circumstances are described by which the trajectory of cortical dynamics may converge to the attractor and precipitate a phase transition, which destroys an existing pattern and initiates a new one.
Prophylaxis in ovarian cancer.

The only prophylaxis for ovarian cancer is oophorectomy, except in the very rare case when an ovarian cancer appears to arise from the mesothelial tissue of the abdominal cavity. It has been shown that women who have taken the oral contraceptive pill for 4 or 5 years decreases the incidence of ovarian cancer by approximately 40%. It is estimated that the oral contraceptive pill can prevent approximately 1500 ovarian cancers each year, The postmenopausal palpable ovary syndrome is simply the palpation of what is interpreted as a normal-sized ovary in the premenopausal woman represents an ovarian tumor in the postmenopausal woman
The effects of clomiphene citrate on the endometrium

Abstract Our experience with clomiphene citrate has been presented. Four categories of patients were investigated. The results with the patients in Groups I and II show that this drug is a promising one for the induction of ovulation. In patients with postmenopausal endometrial hyperplasia, some regression can be anticipated. The role of this drug in the management of endometrial carcinoma cannot be clearly defined at the present time.
Effect of high magnetic fields on the electronic structure of density-wave systems

The effect of high magnetic fields on the electronic structure of some quasi-one-dimensional systems with charge- or spin-density waves is examined. Because of the specific anisotropy of the system, small electron and hole pockets created by the density wave can be destroyed by the presence of a magnetic field. This phenomenon is analyzed for various orientations of the field. The energy spectrum and the density of states in the presence of an external field are calculated for a simple quasi-one-dimensional model band structure. The effect of the magnetic field on the density-wave critical temperature is also calculated. Recent experimental results on ${\mathrm{NbSe}}_{3}$ are analyzed in terms of this theory.
Effects of Protease Inhibitors on Protein Breakdown in Escherichia coli

Abstract In an attempt to learn more about the proteolytic enzymes responsible for protein turnover in cells, the effects of various protease inhibitors on protein catabolism in Escherichia coli were examined. Diisopropyl fluorophosphate, phenylmethane sulfonyl fluoride, and toluenesulfonyl fluoride, all of which inhibit serine proteases, were found to decrease protein breakdown in E. coli, starved for a carbon source. These compounds partially inhibited protein breakdown at doses which did not inhibit growth on minimal medium. The effects of the sulfonyl fluorides were reversed by washing the cells. Protein breakdown in starving cells could also be inhibited reversibly by the aromatic diamidines, dibromopropamidine and pentamidine, which are potent trypsin inhibitors. The effects of pentamidine and p-toluenesulfonyl fluoride did not require concomitant protein synthesis. Tosyl lysine chloromethyl ketone, an inhibitor of trypsin, also inhibited protein breakdown in starving cells. A number of other protease inhibitors were tested and found either to have no effect on intact cells or to prevent normal cell growth. These findings suggest that at least one of the enzymes responsible for the increased protein breakdown in starving cells is a serine protease, possibly similar to trypsin. In cells deprived of a carbon or nitrogen source, synthesis of new enzymes should be dependent upon the breakdown of previously existent cell proteins. Treatment with the sulfonyl fluorides or aromatic diamidines inhibited amino acid incorporation into proteins under such conditions, but did not do so in growing cells. Similarly these compounds reversibly inhibited the induction of β-galactosidase and tryptophanase in cells deprived of a carbon or nitrogen source, but did not do so in cells growing on glycerol. The sulfonyl fluorides, the aromatic diamidines, and tosyl lysine chloromethyl ketone did not reduce the relatively low amount of protein breakdown found in growing cells. Growing cells degrade selectively "abnormal" or "aberrant" proteins, and the rate of protein breakdown in such cells increased markedly when they were grown on amino acid analogs, canavanine or threo-α-amino-β-chlorobutyric acid. This accelerated degradation also was not inhibited by the sulfonyl fluorides or the diamidines. These results thus suggest that there may exist at least two proteolytic systems in E. coli: one operating in all cells, which can degrade abnormal proteins, and one found in starving cells which is sensitive to sulfonyl fluorides and aromatic diamidines.
An X and EWMA chart for individual observations

While there is much experience in monitoring processes with individual observations it is not clear which procedure is best. We compare individual observation control procedures that are combinations of the moving range (MR), exponentially weighted movi..
Low-Temperature Production of Urocanic Acid by Spoilage Bacteria Isolated from Mahimahi (Coryphaena hippurus).

Urocanic acid production was studied in 166 bacterial cultures isolated from mahimahi which had been stored for 14 days on ice in seawater. After 4 days of incubation at 10°C in histidine-supplemented Trypticase soy broth (BBL Microbiology Systems, Cockeysville, Md.), urocanic acid was measured by thin-layer chromatography. Fifty-eight of the cultures were positive for urocanic acid, with the eight most active isolates producing ca. 10 mg/100 ml. These observations, coupled with a report that urocanic acid may be the predominant histidine metabolite in fish held at low temperatures, all suggest that urocanic acid may be a useful alternative to histamine as a spoilage index in scombroid and other fish that are rich in endogenous histidine.
Nonlinear model order reduction of Burgers' Equation using proper orthogonal decomposition

In this paper, we examine a model order reduction approach for dynamic systems governed by Burgers' equation with Neumann boundary conditions. The proper orthogonal decomposition (POD) method is employed here that provides a reliable and accurate modeling approach, while the temporal discretization of the continuous error function leads to a more accurate estimation of the defined cost function. We will investigate the accuracy of the reduced-order model compared to the finite element (FE) model by choosing an adequate number of basis functions for the approximating subspace. The derived lumped-parameter model for Burgers' equation is then described by a nonlinear state-space model. We finally demonstrate the accuracy of the reduced-order model through a numerical example, where we show that a 7-dimensional POD can accurately estimate the system output.
A theoretical study of structural, vibrational, and electronic properties of neutral, positive, and negative indium arsenide clusters, InnAsn(n=1,2,3)

First principles study of the small InAsn clusters is performed to investigate the changes in structural, vibrational and electronic properties, when an electron is either added or removed from the corresponding neutral clusters. The calculated results reveal that the addition of an electron to the neutral clusters induce significant structural changes relative to the case when an electron is removed. The changes in vibrational properties can be explained in terms of the variation of the interatomic distances upon removing or adding the electron. The calculated values of electron affinity and ionization potential are comparable to those calculated in GaAs and InP clusters.
Use of Infrared Spectroscopy in Permeation Tests

The use of infrared (IR) analysis for permeation work has both advantages and disadvantages. Most advantageous is its ability to monitor a permeation test constantly without taking samples, as is necessary for most gas chromatography (GC) systems. Infrared detection also requires little attendance, and breakthrough time is very easy to discern. Disadvantages include a longer delay in detected breakthrough time (because of the volume of the system) than with GC systems. However, the relative error introduced is quite small. Another problem is the necessity to purge the IR gas cell during calibration or before adding a different sample. This makes simultaneous testing of several cells difficult if not impossible. Last, a high static pressure [12.5 to 25 cm (5 to 10 in.) of H 2 O] on the polymer membrane in the ASTM cell is created by the usual high flow rate (5 to 10 L/min) in commonly used IR systems. Although this pressure does not seem to affect permeation, these high flow rates are not necessary, and indeed, lower flow rates will reduce the error in detection of breakthrough time. The calculations and data to support these statements are reported.
Community development and democratic practice: pas de deux or distinct and different?

In this introductory article, we discuss the theme of the Special Issue of Community Development focused on community development and democratic practice. Seven articles are summarized and highlight a range of case studies that vary by location, scale, and purpose, followed by a reflective essay. Drawing from the articles in the Special Issue and a series of joint learning exchanges on the topic sponsored by the Kettering Foundation, we then outline a heuristic framework for “democratic community development.” The framework asks a number of related questions about how democracy, community, and the public are constituted, and what processes, end goals, methods, and tools are to be used to further democratic community development.
The essential visibility graph: an approach to global motion planning for autonomous mobile robots

An approach to global motion planning for autonomous mobile robots has been developed on the basis of traversability vectors (t-vectors). Through the overall course of this research it was found that t-vectors provide a utility, efficiency and mathematical stability for collision detection and visibility that cannot be matched by commonly used algebraic approaches in static and dynamic environments. This paper will show that t-vectors also impact global motion planning by identifying redundancies in visibility graphs (V-graphs) and expediting their construction. The result of eliminating redundant path segments is a streamlined version of the V-graph called the essential visibility graph (EVG). This paper will also show that the EVG offers a significant reduction in data storage requirements and complexity.
Nanostructure based electro-optic modulators for high speed optical interconnects

We are currently developing a CMOS compatible optical modulator based on semiconductor nanostructure arrays that has the potential to provide large modulation depths as well as very high operation speeds. The basis of the expected performance improvements are the strong non-linear and electro-optic effects that occur in low dimensional nanostructures due to quantum confined Franz-Keldysh effect and quantum confined Stark effect. The nanostructures are fabricated by a novel thin film template-based synthesis technique that is CMOS compatible. The technique is based on the anodization, or electrolytic oxidation, of a thin film of aluminum to form a nanoporous alumina template, which guides the synthesis of the semiconductor nanostructures.
Geochemical comparison of impact glasses from lunar meteorites ALHA81005 and MAC88105 and Apollo 16 regolith 64001

Parameterizations have been developed for impact glass compositions which makes its possible to acquire geochemical information about pre-impact target materials. The impact glass populations among unrelated highland regoliths including Apollo 16 regolith 64001 and the lunar meteorites ALHA81005 and MAC88105 have been compared. It is concluded that the Apollo 16 impact glasses are compositionally more diverse than those in the lunar meteorites. This diversity reflects the complex geology of the Apollo 16 region, in which extensive exposures of mare basalts occur within 300 km. Apollo 16 regolith 64001 contains a distinctive subset of impact glasses with major element compositions similar to lunar highland meteorite. These impact glasses (less than 100 micrograms) indicate that the lunar highlands are geochemically more diverse than the compositional range currently represented by large (more than 1 gram) samples. Lunar impact glasses provide geochemical constraints on the full range of regolith compositions that occur on the moon.
Development of a correlation for aqueous-vapor phase mass transfer in porous media

Abstract In many situations vapor-phase extraction procedures (e.g., soil venting, air sparging, and bioventing) may be suitable methods for remediating porous media contaminated by volatile organic compounds. This has led to increased study of operative processes in these systems, including aqueous-vapor phase mass transfer. Past work has shown the importance of the flow regime on this process, but a quantitative estimate of mass-transfer coefficients is lacking, especially for systems not confounded by uncertainties involving interfacial area between the phases. An experimental investigation was conducted to isolate the resistance to aqueous-vapor phase mass transfer at the phase boundary, using an ideal porous medium system. Mass-transfer coefficients were measured for toluene for a wide range of Reynolds numbers. An empirical model was fit to the data in dimensionless form. The mass-transfer model was coupled with an available interfacial area model, yielding a dimensionless expression for the mass-transfer rate coefficient. This expression was used to compare results from this work to three other experimental studies reported in the literature. These comparisons showed that for experiments where infiltrating water flowed uniformly within the porous medium, the predicted mass-transfer coefficients were within a factor of 5 of the measured coefficients. Mass transfer was significantly slower than the rate predicted, using the results from this work, in experiments where infiltrating water flowed nonuniformly.
Multiculturalism in New Italian Cinema

AbstractMany factors contributed in the last 30 years to bring to the fore the need for a new representation of the Italian nation in the media. They span from the local economic boom to the combination of global political events—the widespread process of de/counter-colonization, the demise of communist/socialist/dictatorial regimes in Eastern Europe, the poverty and the climate of terror in North Africa, the dissolution of the Yugoslavian federation, Italy joining the European Union and so forth—and they all contributed to the formation of a wave of mass immigration in the peninsula. On a daily basis, since the early nineties, mass immigration prompts the country to re-think its identity in terms of culture, religion, heritage, and to resituate itself in a European and global context, and while in literature the hyphenated identities of the contemporary diasporic writers begin to emerge, the televisual and cinematic representation of their correlatives is still missing or incomplete. As a rule, the patri...
Select gas absorption in carbon nanotubes loading a resonant cavity to sense airborne toxin gases

A gas-sensing probe has been investigated that involves the use of microwave resonant circuitry to detect frequency shifts/Q-changes in a resonant microwave cavity caused by absorption of chemical/biological agents onto carbon nanotubes (CNTs). Tests were made with single walled (SWNTs) to determine maximum selectivity of the probe. The ultimate goal is to accumulate a battery of test data for selected gases to establish a comprehensive inventory of potential gases that can be sensed with the apparatus. Additionally, it is anticipated that this work will result in a significant simplification of the design of the probe as well as the determination of an optimum frequency for probing with the cavity. Data presented in this work is offered as a demonstration of the feasibility of the instrument to detect non-toxic gases. As development continues, the device should be able to detect a wider range of gases including airborne toxins. Particle induced X-ray emission (PIXE) was used to characterize the impurities within the SWNTS to better understand the nature of the coupling of the microwave with the nanostructured material and ultimately to determine how impurities affect the sensitivity of the probe.
GaAs: Cr 3 + ( 3 d 3 ) —an orthorhombic Jahn-Teller center with a stress-dependent reorientation rate

The ${\mathrm{Cr}}^{3+}(3{d}^{3})$ EPR center in GaAs has been investigated using controlled uniaxial stress at temperatures from 1.8 to 4.2 K. Stresses up to 1200 kg/${\mathrm{cm}}^{2}$ were applied along the [001], [111], [110], and [112] axes. The rapidity of stress alignment of the distortions at 1.8 K shows that the orthorhombic symmetry arises from a Jahn-Teller (JT) effect. At high stress levels, the populations of the favored distortions behave as expected for a static JT effect. As the stress is reduced to low levels, however, the signal amplitudes decrease anomalously while the linewidths increase. Simultaneously, the lines develop Lorentzian tails and shift somewhat in position, and even at 1.8 K there is no microwave saturation. This behavior suggests a rapid reorientation between nearly equivalent distortions at low (or zero) applied stress which is quenched at high stress. The single-phonon-induced reorientation rate is shown to be stress dependent and can give rise to line broadening (fast reorientation) at low stress. A model based on this and a Boltzmann distribution over the different distortions gives semiquantitative agreement with the normalized signal amplitudes from the energetically favored distortions. The data show that the center couples strongly to both E and ${\mathrm{T}}_{2}$ modes and the Jahn-Teller coupling coefficients are determined. The E and ${\mathrm{T}}_{2}$ couplings are nearly equal in the sense of O'Brien and this is responsible for the fast low-temperature reorientation ($\ensuremath{\tau}\ensuremath{\simeq}0.3$ ns at 1.8 K). For $\stackrel{\ensuremath{\rightarrow}}{\mathrm{P}}\ensuremath{\parallel}[001]$ an observed $\frac{P}{T}$ scaling of the data and a splitting of the 4-kG EPR line at low stress remain unexplained.
Shut up and listen: applied critical race theory in the classroom

This paper demonstrates that applying critical race theory to the classroom dramatically shifts the nature and scope of schooling for students of color in urban schools. In focusing on students, applied critical race theory centers the development of voice and expression, and de‐centers the high‐stakes pressures that limit student engagement. This overview of a writing class at a continuation high school clarifies the importance of student voice, but also of knowing how to engage in dialogue with students about the social context they navigate daily. Understanding how to foster critical voice in students provides educators the tools to create engaging classrooms, and acknowledges the intense emotional experiences that students bring (from home contexts) to the classroom. Without such acknowledgement at the core of schooling, educators are likely to reinforce the very stereotypes that lead students to reject what they often see as demeaning education. The article demonstrates instructional techniques that ...
Data interrogation for Fabry-Perot whitelight interferometry

Among various optical fiber distance sensing techniques, optical fiber sensors based on white-light Fabry-Perot interferometry offer the simplest configuration, the highest sensitivity, and the most precise distance measurement. Because a whitelight interferometric sensor can overcome the directional ambiguity problem encountered by the other interferometric techniques, it is especially attractive for applications where absolute distance measurement is desired. However, conventional two-fringe matching data demodulation technique can induce a half wavelength error to the distance measurement. In this paper, we present an improved fringe matching data interrogation technique that can overcome this problem. The data interrogation scheme consists of two steps: a rough estimation of the distance and the phase shift using the two fringe matching technique and a more precise estimation of the distance and the phase shift using the correctional terms derived from the fringe difference. Simulation results indicate that the algorithm can converge to the correct distance with sub-Armstrong accuracy over a large dynamic range.
Responses of optical amplifier to optical bursts

Responses of an optical amplifier to optical bursts with different type and different frequency are studied. Amplifier behaviours in constant gain, constant power and constant current operation modes are compared with each other.
Collateral benefits from public and private conservation lands: a comparison of ecosystem service capacities

Protected areas remain the most commonly used tool for in situ conservation; however growth in the USA's system of public lands has stagnated while private land conservation continues to expand. Easements can provide a range of ecosystem services (ESs), but it is unknown whether conservation easements maintain ES capacities equivalent to public protected areas. Evaluation of the capacity of seven ESs on federal and state protected areas and conservation easements in the USA using spatially-explicit ES models and publicly available data indicated that ES capacities in easements were equal to or greater than capacities within state or federal protected areas for six of seven services and, when bundled together, conservation easements protected greater focal ES capacity than other conservation areas. Economic incentive programmes and regulatory mechanisms may be used to stimulate capacity improvements for surface water regulation, riparian filtration, erosion control, and carbon storage on conservation easements, and landscape-level conservation efforts should (1) continue to protect natural and uninhabited areas that provide ecosystem and biological diversity, (2) expand private conservation efforts close to human population centres, and (3) limit future development to areas with high regulating service capacity that can sustain new population growth.
Kinetics of transitions involving condis crystals

The kinetics of condis (conformationally disordered) crystal formation from the melt and of rigid crystals from condis crystals has been studied by differential scanning calorimetry for trans-1,4-polybutadiene and polytetrafluoroethylene. Generally very low two-stage Avrami exponents between 0.02 and 1.74 were needed to describe the fast and often incomplete crystallizations. None of the commonly accepted crystal nucleation and growth models seems to fit the data.
Women's Perceptions of the Prison Environment: When Prison is “The Safest Place I'VE Ever Been”

Incarcerated women’s perceptions of the prison environment were explored with respect to relative level of safety from interpersonal abuse in prison as compared to before incarceration. Perceived levels of safety were analyzed based on reported past experiences of interpersonal violence. Participants were 65 women incarcerated in a medium security prison for women with mental and physical health problems. Women’s perceptions of safety were evaluated using closeended quantitative and open-ended qualitative self-report questions. The results suggest that, for some women, prison may be a relatively safe environment and that perceived level of safety may vary with the extent of previous experience of interpersonal violence in childhood and adulthood. Given that the structure of correctional institutions often incorporates abusive dynamics, the directionality of the findings is theoretically and socially important. The patterns apparent in these data are also consistent with other research and theory on the experiences of incarcerated women. In the last 15 years, the number of incarcerated women in the United States has increased dramatically. According to the U.S. Department of Justice Bureau of Justice Statistics (1999), 950,000 women (i.e., approximately 1% of the U.S. female population) are currently “under the care, custody, or control of federal, state or local corrections.” Eighty-five percent of these women are supervised in the community by probation or parole, whereas approximately 150,000 women are incarcerated in U.S. jails or prisons. Moreover, women are the fastest growing group of people involved in the criminal justice system (Powell, 1999). Incarcerated women, as compared to the general population of women, are disproportionately likely to have experienced interpersonal victimization prior to incarceration (Chesney-Lind, 1997). However, the rates of abuse reported by incarcerated women are consistent with rates reported by homeless and housed poor women (Browne & Bassuk, 1997). Browne, Miller, and Maguin (1999) conducted one of the most comprehensive studies to date examining the prevalence of pre-prison interpersonal violence among incarcerated women. Their sample included 150 women incarcerated in a New York state prison. They reported a 59% rate of childhood sexual abuse, a 70% rate of child physical abuse by a caretaker, a 49% rate of rape as an adult, and a 75% rate of “severe” physical abuse by an
Insect Control in Socialist China and the Corporate United States: The Act of Comparison, the Tendency to Forget, and the Construction of Difference in 1970s U.S.–Chinese Scientific Exchange

ABSTRACTIn 1975, a delegation of U.S. entomologists traveled to socialist China to observe Chinese insect control science. Their overwhelmingly positive reports highlighted in relief the pernicious effects of pesticide corporations on U.S. agriculture; some entomologists hoped this would goad the United States to catch up to China in environmentally sensible insect control practices. Of course, insect control in socialist China carried its own political baggage, some of which—for example, mass mobilization and self-reliance—the state made highly visible to visitors, and some of which—for example, harsh treatment of scientists—it sought to obscure. For both the U.S. and the Chinese participants, the act of comparison itself was of primary significance in the exchange, allowing them to construct socialist Chinese science as refreshingly different from U.S. science. At the same time, however, this construction of difference meant forgetting the much longer transnational history in which U.S. and Chinese ento...
Reversing DNA Methylation: New Insights from Neuronal Activity–Induced Gadd45b in Adult Neurogenesis

Neurogenesis in the adult mammalian brain involves activity-dependent expression of genes critical for the proliferation of progenitors and for neuronal maturation. A recent study suggests that the stress response gene Gadd45b (growth arrest and DNA-damage-inducible protein 45 beta) can be transiently induced by neuronal activity and may promote adult neurogenesis through dynamic DNA demethylation of specific gene promoters in adult hippocampus. These results provide evidence supporting the provocative ideas that active DNA demethylation may occur in postmitotic neurons and that DNA methylation-mediated dynamic epigenetic regulation is involved in regulating long-lasting changes in neural plasticity in mammalian brains.
Homotopic and heterotopic callosal afferents of caudal inferior parietal lobule in Macaca mulatta.

We have examined callosal-axon neurons giving rise to homotopic and heterotopic callosal projections to caudal inferior parietal lobule (area PG) in Macaca mulatta, identifying these neurons by means of retrograde axonal transport of horseradish peroxidase. The labeled neurons in the homotopic region occur predominantly in layers IIIB and V.A moderate number are also seen in layer VI, a smaller number of layer IV, and rare cells occur in layer II. These neurons occupy a region very similar in outline to the injection area, and though variable in density in the horizontal plane, are continuously distributed in this plane. The heterotopic neurons are seen in the contralateral cingulate gyrus, continuing caudally into medial parietal cortex, in the cortex of the superior temporal and occipitotemporal sulci, in the caudal superior temporal gyrus, and in the caudal inferior parietal lobule, behind the homotopic area. These same regions on the ipsilateral side contain labeled neurons of origin of ipsilateral association projections to area PG. For other ipsilateral labeling was found. A review of the literature on heterotopic callosal connections of a particular generalization of this conclusion: The callosal heterotopic connections of a particular cortical area are made with regions which on the ipsilateral side have associated connections with that area, though usually not with all of such regions.
Maximization and minimization of complicated multivariable functions

This paper is intended as a review and appraisal of various existing methods of finding singular points (maxima, minima, or saddle points) in functions of many variables. It is limited to methods involving a search procedure rather than a formal analytical technique. These methods are useful whenever an optimum condition is required of a system too complex for conventional analytical techniques.
STRUCTURE AND CHEMICAL COMPOSITION OF CRANBERRY CELL WALL MATERIAL

The microscopic examination of cell wall material recovered from pressed cranberries indicated that the tissue particles were composed primarily of parenchyma cell walls that had reassumed a three-dimensional configuration similar to their structure in cranberry parenchyma tissue. Settling experiments indicated that large volumes of water were associated with cell wall material, correctly predicting when suspension yield stress would increase. The primary plant cell wall polysaccharides, cellulose, pectin and hemicellulose, were found to be the predominant constituents of cell wall material. Protein, fat, starch and ash were present in only minor amounts suggesting that cell wall material food functionality will be primarily dependent on the polysaccharide constituents.
Extracellular matrix, cell skeletons, and embryonic development

During embryonic development, the extracellular matrix (ECM) promotes the production of differentiated products by epithelial cells and the migration of mesenchymal cells, and probably also plays a role in epithelial-mesenchymal transformation. Here we examine the role of the cell skeleton (actin, microtubules, intermediate filaments) in mediating matrix effects on mesenchymal cell morphology, migration, and formation. The interaction of both epithelial cells and mesenchymal cells with ECM seems to involve the actin cortex, which is best developed in the base of the epithelial cell, where it attaches to underlying matrix via membrane-intercalated receptors. To interact with the matrix, the fibroblast has appropriate ECM receptors and an actin cortex around the whole cell. The actin cortex is absolutely required for assumption of bipolar shape, elongation, and movement through the matrix. Since the cortex seems to be anchored to the matrix, it is unlikely that it moves during cell migration. A new hypothesis states that the microtubule- and intermediate filament-rich endoplasm, containing the nucleus, moves past the actin cortex-receptor-matrix complex into the newly synthesized front end of the mesenchymal cell to effect forward movement. When epithelial cells transform into mesenchyme in the embryo, or when they are induced to do this in vitro, they switch from the keratin intermediate filament profile to one rich in vimentin, and the effect of cell matrix interaction on cell shape is profoundly altered. Vimentin-actin interactions with ECM may be a major factor in the ability of a cell to become mesenchymal.(ABSTRACT TRUNCATED AT 250 WORDS)
Notes on the Measurement of Reactive Volt-Amperes

In the following paper, the character of the quantity known as reactive volt-amperes is first discussed and its dependence on the assumption of a definite type of periodicity is brought out, this in contrast to certain other a-c quantities. It is pointed out that on account of the rather complicated relation that it bears to the flow of energy in an electric circuit serious difficulties are met in its measurement except in the simpler conditions of balanced voltages, in a polyphase circuit, and sinusoidal waves. Two procedures are outlined which though they are not premised on balanced voltages have frequency and wave form limitations. In the latter part of the paper, the relation of the quantity of energy that surges in an a-c circuit in which there is energy storage, to the average flow of energy is considered, and advantages of this conception as a basis for rates are indicated. Finally, it is pointed out that reactive volt-amperes is of the nature of a complementary quantity rather than a specific activity of the electric circuit which when suitably combined with power gives volt-amperes.
Examining the Effect of the Dipole Moment on Charge Separation in Donor–Acceptor Polymers for Organic Photovoltaic Applications

A new low band gap copolymer PBB3 containing [6,6′]bi[thieno[3,4-b]thiophenyl]-2,2′-dicarboxylic acid bis-(2-butyloctyl) ester (BTT) and 4,8-bis(2-butyloctyl)benzo[1,2-b:4,5-b′]dithiophene (BDT) units was synthesized and tested for solar cell efficiency. PBB3 showed a broad absorbance in the near-IR region with a substantially red-shifted (by more than 100 nm) λmax at 790 nm as compared to the PTB series of polymers, which have been previously reported. The PBB3 polymer also showed both a favorable energy level match with PCBM (with a LUMO energy level of −3.29 eV) and a favorable film domain morphology as evidenced by TEM images. Despite these seemingly optimal parameters, a bulk heterojunction (BHJ) photovoltaic device fabricated from a blend of PBB3 and PC71BM showed an overall power conversion efficiency (PCE) of only 2.04% under AM 1.5G/100 mW cm–2. The transient absorption spectra of PBB3 showed the absence of cationic and pseudo charge transfer states that were observed previously in the PTB series...
Io: Loki Patera as a magma sea

We develop a physical model for Loki Patera as a magma sea. We calculate the total volume of magma moving through the Loki Patera volcanic system every resurfacing cycle (approx.540 days) and the resulting variation in thermal emission. The rate of magma solidification at times reaches 3 x 10(exp 6) kg per second, with a total solidified volume averaging 100 cu km per year. A simulation of gas physical chemistry evolution yields the crust porosity profile and the timescale when it will become dense enough to founder in a manner consistent with observations. The Loki Patera surface temperature distribution shows that different areas are at different life cycle stages. On a regional scale, however, there can be coordinated activity, indicated by the wave of thermal change which progresses from Loki Patera's SW quadrant toward the NE at a rate of approx.1 km per day. Using the observed surface temperature distribution, we test several mechanisms for resurfacing Loki Patera, finding that resurfacing with lava flows is not realistic. Only the crustal foundering process is consistent with observations. These tests also discovered that sinking crust has a 'heat deficit' which promotes the solidification of additional magma onto the sinking plate ("bulking up"). In the limiting case, the mass of sinking material can increase to a mass of approx.3 times that of the foundering plate. With all this solid matter sinking, there is a compensating upward motion in the liquid magma. This can be in excess of 2 m per year. In this manner, solid-liquid convection is occurring in the sea.
Marking NEP's Slippery Path: The Krasnoshchekov Show Trial

Comrades are raising an uproar—you are strangling the economic managers. Every time that a manager is dealt with, we experience huge difficulties. We were not able to arrest Krasnoshchekov right away, and many comrades doubted that it was possible to arrest him. ... I think that we will completely lose the respect of the broad working masses if we do not act in such instances. We sometimes fear to compromise a rabotnik and put him on trial, when the case concerns great abuses, and when such a trial aims not just to punish the guilty, but also to teach other comrades how to stay on this slippery path.
KSHV induces heme oxygenase: another trick by a wily virus

NEOPLASIA Research on Kaposi sarcoma (KS) was given a shot in the arm with the discovery in 1994 of Kaposi sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus-8 (HHV-8).[1][1] This virus is an etiological agent for KS and also for primary effusion lymphoma (PEL), multicentric
Comparative analysis of hierarchical triangulated irregular networks to represent 3D elevation in terrain databases

Three-dimensional terrain representation plays an important role in a number of terrain database applications. Hierarchical triangulated irregular networks (TINs) provide a variable-resolution terrain representation that is based on a nested triangulation of the terrain. This paper compares and analyzes existing hierarchical triangulation techniques. The comparative analysis takes into account how aesthetically appealing and accurate the resulting terrain representation is. Parameters, such as adjacency, slivers, and streaks, are used to provide a measure on how aesthetically appealing the terrain representation is. Slivers occur when the triangulation produces thin and slivery triangles. Streaks appear when there are too many triangulations done at a given vertex. Simple mathematical expressions are derived for these parameters, thereby providing a fairer and a more easily duplicated comparison. In addition to meeting the adjacency requirement, an aesthetically pleasant hierarchical TINs generation algorithm is expected to reduce both slivers and streaks while maintaining accuracy. A comparative analysis of a number of existing approaches shows that a variant of a method originally proposed by Scarlatos exhibits better overall performance.
The coarse Baum–Connes conjecture for spaces which admit a uniform embedding into Hilbert space

Corollary 1.2. Let Γ be a finitely generated group. If Γ, as a metric space with a word-length metric, admits a uniform embedding into Hilbert space, and its classifying space BΓ has the homotopy type of a finite CW complex, then the strong Novikov conjecture holds for Γ, i.e. the index map from K∗(BΓ) to K∗(C∗ r (Γ)) is injective. Corollary 1.2 follows from Theorem 1.1 and the descent principle [23]. By index theory, the strong Novikov conjecture implies the Novikov conjecture on the homotopy invariance of higher signatures (cf. [8] for an excellent
Deformation Processed Metal–Metal Composites

Deformation processed metal–metal composites (DMMCs) are composites in which both the matrix and the reinforcing phase are ductile metals. The ductility of the metals permits the composite to be heavily deformed by drawing or rolling to reduce the thickness and spacing of the two phases to as small as 10 nm. Their nano-scale microstructures are exceptionally strong, with strengths approaching whisker strength in some cases. And since the materials are comprised of two essentially pure metals, their electrical conductivities are quite high for current flow in directions parallel to the composite’s filaments or lamellae, leading to numerous potential applications. During the 1990s, continuing research has produced DMMCs in a wide range of matrix metals, including Al, Au, Mg, Sc, and Ti. Methods are also being developed to produce DMMCs with much larger dimensions in rod and sheet forms to permit their use in a wider variety of engineering applications.
Differentiation of a precise timing response

Humans, monkeys, and rats were trained by a process of successive differentiations to press a bar for at least 1.00 sec but for no longer than 1.27 sec. Initially, animals were reinforced for all responses, then a minimum duration of response was gradually differentiated, below which no responses were reinforced. Finally, a maximum duration of response was differentiated above which no responses were reinforced. The duration of response in all three species approximated the minimum duration of response necessary for reinforcement. As the duration of response necessary for reinforcement increased, so did the mean duration of response in the three species. As the maximum allowable duration decreased, further compression of the mean occurred. The fact that the acquisition of the differentiation was approximately the same in all three species is a further indication of the control reinforcement exerts on operant responding.
Comparison of hyperfine anomalies in the 5S1/2 and 6S1/2 levels of 85Rb and 87Rb

Abstract We observe a hyperfine anomaly in the measurement of the hyperfine splitting of the 6 S 1 / 2 excited level in rubidium. We perform two step spectroscopy using the 5 S 1 / 2 → 5 P 1 / 2 → 6 S 1 / 2 excitation sequence. We measure the splitting of the 6 S 1 / 2 level and obtain for the magnetic dipole constants of 85Rb and 87Rb A = 239.18 ( 4 ) MHz and A = 807.66 ( 8 ) MHz , respectively. The hyperfine anomaly difference of δ 85 87 = − 0.0036 ( 2 ) comes from the Bohr Weisskopf effect: a correction to the point interaction between the finite nuclear magnetization and the electrons, and agrees with that obtained in the 5 S 1 / 2 ground state.
Miniature fuses for appliance circuits' protection

This discussion of miniature fuses traces the development of miniature fuses, compares various types of fuses, compares the specifications for miniature fuses and service circuit breakers, and offers some recommendations which it is felt will be of definite benefit to both the fuse industry and the appliance industry in general.
Don't call it a highway!

Where did the information superhighway come from? Highways and information technology seem to have nothing in common. The author discusses the use of the term "highway", and considers its unsuitability for IT.
Nursing students with latex allergy

Latex allergy affects millions of people in the general population and a higher percentage of health care workers. Nursing students with a latex sensitivity pose a unique challenge for the nurse educator. Students may enter the program with pre-existing latex allergy or develop the allergy during the educational process. This manuscript explores the implications of latex allergies exhibited by the nursing student. It addresses the responsibilities of the educator in the skills or simulation laboratory and during clinical learning experiences. It also offers suggestions for ensuring the safety of the student while reducing the legal liabilities of the educational program. The article addresses possible policy ramifications for nursing schools.
CD4+CD25+ T cells: friends or foes?

Like the mythical Hydra that grew new heads after being apparently successfully decapitated, the concept of the suppressor T cell never quite goes away, re-emerging at intervals—currently as the regulatory T (Treg) cell. Questions regarding the nature of such cells persist. One such population,