cssi/SciSciGPT-SciSciNet huggingface dataset:
Social Dimensions of Office Automation

Publisher Summary This chapter focuses on the social implications of office automation, and describes the effects of office automation on people and organization. Office automation is a controversial subject which amplifies residual biases present in all studies of social impacts of technology. Study of office automation begins with an examination of productivity in the office. The chapter discusses different approaches to automation, the impact of office automation on employment (based on employment levels, skill requirements, and career paths), some key policy issues concerning the effects of automation on employment, changing skill levels in clerical and professional work, the policies of organized labor and union responses to the challenges posed by office automation, and the organizational and managerial implications of office automation. The literature on computers and organizations is being reviewed that focuses on the computer's role in decision making and problem solving. The chapter concludes by discussing the future of work. Since work is a central concern in office automation, it is natural to consider its future at the end of the study.
NR2B‐NMDA receptor mediated modulation of the tyrosine phosphatase STEP regulates glutamate induced neuronal cell death

The present study examines the role of a neuron-specific tyrosine phosphatase (STEP, striatal-enriched tyrosine phosphatase) in excitotoxic cell death. Our findings demonstrate that p38 MAPK, a stress-activated kinase that is known to play a role in the etiology of excitotoxic cell death is a substrate of STEP. Glutamate-mediated NMDA receptor stimulation leads to rapid but transient activation of p38 MAPK, which is primarily dependent on NR2A-NMDA receptor activation. Conversely, activation of NR2B-NMDA receptors leads to dephosphorylation and subsequent activation of STEP, which in turn leads to inactivation of p38 MAPK. Thus, during transient NMDA receptor stimulation, increases in STEP activity appears to limit the duration of activation of p38 MAPK and improves neuronal survival. However, if NR2B-NMDA receptor stimulation is sustained, protective effects of STEP activation are lost, as these stimuli cause significant degradation of active STEP, leading to secondary activation of p38 MAPK. Consistent with this observation, a cell transducible TAT-STEP peptide that constitutively binds to p38 MAPK attenuated neuronal cell death caused by sustained NMDA receptor stimulation. The findings imply that the activation and levels of STEP are dependent on the duration and magnitude of NR2B-NMDA receptor stimulation and STEP serves as a modulator of NMDA receptor dependent neuronal injury, through its regulation of p38 MAPK.
The Los Alamos 600 MJ, 1500 MW Inertial Energy Storage And Pulsed Power Unit

A 1430 MVA synchronous generator from a cancelled nuclear power plant has been installed and commissioned at Los Alamos National Laboratory (LANL) to be used as the pulsed power generator for physics experiments. The generator is mounted on a spring foundation to prevent dynamic forces from being transmitted to the substructure and into the ground. A 6 MW load-commutated inverter drive accelerates the machine from standstill to the maximum operating speed of 1800 rpm and from 1260 rpm to 1800 rpm between load pulses. The generator cooling method has been changed from hydrogen to air cooling to facilitate operation. A current limiting fuse, with a fuse clearing current of 90 kA, will protect the generator output against short circuit currents. An overview of the installation is presented. The paper also addresses the overload capability of the generator for pulsed loads. 7 figs., 1 tab.
Human Memory Cytotoxic T-Lymphocyte (CTL) Responses to Hantaan Virus Infection: Identification of Virus-Specific and Cross-Reactive CD8+ CTL Epitopes on Nucleocapsid Protein

Hantaan virus, the prototypic member of the Hantavirus genus, causes hemorrhagic fever with renal syndrome in humans. We examined the human memory T-lymphocyte responses of three donors who had previous laboratory-acquired infections with Hantaan virus. We demonstrated virus-specific responses in bulk cultures of peripheral blood mononuclear cells (PBMC) from all donors. Bulk T-cell responses were directed against either Hantaan virus nucleocapsid (N) or G1 protein, and these responses varied between donors. We established both CD4(+) and CD8(+) N-specific cell lines from two donors and CD4(+) G1-specific cell lines from a third donor. All CD8(+) cytotoxic T-lymphocyte (CTL) lines recognized one of two epitopes on the nucleocapsid protein: one epitope spanning amino acids 12 to 20 and the other spanning amino acids 421 to 429. The CTL lines specific for amino acids 12 to 20 were restricted by HLA B51, and those specific for amino acids 421 to 429 were restricted by HLA A1. The N-specific CTL lines isolated from these two donors included both Hantaan virus-specific CTLs and hantavirus cross-reactive CTLs. Responses to both epitopes are detectable in short-term bulk cultures of PBMC from one donor, and precursor frequency analysis confirms that CTLs specific for these epitopes are present at relatively high precursor frequencies in the peripheral T-cell pool. These data suggest that infection with Hantaan virus results in the generation of CTL to limited epitopes on the nucleocapsid protein and that infection also results in the generation of cross-reactive T-cell responses to distantly related hantaviruses which cause the distinct hantavirus pulmonary syndrome. This is the first demonstration of human T-lymphocyte responses to Hantaan virus.
Mesoporous scaffolds based on TiO2 nanorods and nanoparticles for efficient hybrid perovskite solar cells

In a mesoporous hybrid perovskite solar cell (PSC), the mesoporous scaffold plays key roles in controlling the crystallization of the perovskite material and in the charge carrier transport, and hence is critical for developing highly efficient PSCs. Here we report a study on blending micrometer-long TiO2 nanorods (NRs) into the commonly used nanoparticles (NPs) to optimize the mesoporous structure, with the aim of enhancing the perovskite material loading and connectivity as well as light harvesting. It was found that with 5–10% of NR incorporation, a uniform scaffold can be spin-coated and the PSC performance was improved. In comparison to the pure NP-based device, the power conversion efficiency was increased by about 27% when 10% of the NRs were incorporated, due to enhanced light harvesting and charge collection. However, with more NR blending, a homogeneous scaffold cannot be formed, resulting in PSC performance degradation. These findings contribute to a better design of mesoporous scaffolds for high-performance PSCs.
Polymer chemistry: Still in control

The development of synthetic strategies enabling the fabrication of well-defined polymer–biomolecule conjugates, together with advances in top-down nanofabrication, are two highlights from a recent meeting of polymer scientists.
Gene transfer by lipofection in rabbit and human secretory epithelial cells

Lipofection, a recently-developed method for gene transfer, was tested in secretory epithelial cells. Lipofection facilitated both transient DNA transfection with plasmids containing the chloramphenicol acetyltransferase gene and stable transfection with a plasmid containing the neomycin resistance gene, which confers resistance to the antibiotic G418 (Geneticin). Gene transfer occurred efficiently in a rabbit kidney medullary thick ascending limb cell line and in primary cultures of rabbit tracheal epithelial cells. The method was also effective in Simian virus 40-transformed human airway cells isolated from a normal individual and from a patient with cystic fibrosis (CF). Cytotoxicity was minimal, particularly when the time of exposure to the lipofectin-DNA was limited to 3–5 h (< 5% cell loss). Thus, the lipofection method is useful for gene transfer in a variety of secretory epithelial cells and should be ideal for studies of defective secretory epithelial cell function in CF.
Comparison of two active HeT-A retroposons of Drosophila melanogaster.

HeT-A elements are Drosophila melanogaster LINE-like retroposons that transpose to broken chromosome ends by attaching themselves with an oligo(A) tail. Since this family of elements is believed to be involved in the vital function of telomere elongation in Drosophila, it is important to understand their transposition mechanism and the molecular aspects of activity. By comparison of several elements we have defined here the unit length of HeT-A elements to be approximately 6 kb. Also, we studied an active HeT-A element that had transposed very recently to the end of a terminally deleted X chromosome. The 12 kb of newly transposed DNA consisted of a tandem array of three different HeT-A elements joined by oligo(A) tails to each other and to the chromosome end broken in the yellow gene. Such an array may have transposed as a single unit or resulted from rapid successive transpositions of individual HeT-A elements. By sequence comparison with another recently transposed HeT-A element, conserved domains in the single open reading frame (ORF), encoding a gag-like polypeptide, of these elements were defined. We conclude that for transposition an intact ORF is required in cis, while the reverse transcriptase is not encoded on the HeT-A element but is provided in trans. This would make HeT-A elements dependent on an external reverse transcriptase for transposition and establish control of the genome over the activity of HeT-A elements. This distinguishes the Drosophila HeT-A element, which has been implicated in Drosophila telomere elongation, from the other, ‘selfish’ LINE-like elements.
Diffusion of particles in a slowly modulated wave

Abstract Particle motion in the trapping/detrapping regime of a slowly modulated wave is studied. It is shown that separatrix crossing causes diffusion of the adiabatic invariant J . As a result, the trajectories are ergodic throughout separatrix-swept phase space. A lowest-order diffusion coefficient, D 0 ( J ), is calculated by neglecting correlations between separatrix crossings. This theory predicts that the characteristic diffusion time, τ, should scale as the inverse cube of the modulation frequency. Numerical simulations confirm this scaling of τ, but indicate that correlations significantly affect the rate of diffusion.
Lyapunov exponents of nilpotent Itô systems

In all previous work on Lyapunov exponents for stochastic systems, the results take the form of asymptotic power series expansions in the noise parameter. In this paper we consider a natural class ...
LOVE IN THE UNIDIVERSE : A SALESIAN PERSPECTIVE ON CHANCE

The notion of the universe evolving through an interplay of law and chance raises numerous theological questions. In particular, scientific evidence of chance confronts images of God and divine action within this emerging worldview. To interpret Christian faith within a scientific world, figures from church tradition are drawn into the conversation, and a particular spirituality is appropriated to highlight the relationship between science and religion. The personal, practical, accessible spirituality of Saint Francis de Sales is retrieved for the discussion. This Christian humanist recognized the love of God as paramount to a human-divine relationship. The themes of divine providence and the will of God illustrate a spirituality of the heart that provides relevant insights into the theological implications of chance. An overview of how the reality of chance has posed numerous questions is considered before drawing on the spirituality of de Sales. Various theological views on chance are presented. As Salesian thought enhances an understanding of divine action in a world of chance, contemporary theologies of chance provide a framework for understanding the teachings of the saint in a new way.
The relative Dixmier property for inclusions of von Neumann algebras of finite index

Abstract We prove that if an inclusion of von Neumann algebras N ⊂ M has a conditional expectation E : M → N satisfying the finite index condition E (x) ≥ cx, ∀x ϵ M +, for some c > 0, then N ⊂ M satisfies the relative version of Dixmier's property on averaging elements by unitaries in N , i.e., for any x ϵ M , the norm closure of the convex hull of {uxu∗ ∥ u unitary element in N } contains elements of N ′ ∩ M . Moreover, in the case N, M are factors of type II1 and N has separable predual, the finiteness of the index of the inclusion is proved equivalent to the relative Dixmier property and to the property that a normal state on N has only normal state extensions to N . We give applications of these results.
Targeted disruption of Mig-6 in the mouse genome leads to early onset degenerative joint disease

Degenerative joint disease, also known as osteoarthritis, is the most common joint disorder in human beings. The molecular mechanism underlying this disease is not fully understood. Here, we report that disruption of mitogen-inducible gene 6 (Mig-6) in mice by homologous recombination leads to early onset degenerative joint disease, which is revealed by simultaneous enlargement and deformity of multiple joints, degradation of articular cartilage, and the development of bony outgrowths or osteophyte formation within joint space. The osteophyte formation appears to be derived from proliferation of mesenchymal progenitor cells followed by differentiation into chondrocytes. Absence of the Rag2 gene does not rescue the joint phenotype, excluding a role for the acquired immune system in the development of this disease. Our results provide insight into the mechanism of osteoarthritis by showing that loss of Mig-6 leads to early onset of this disease, implying that this gene or its pathway is important in normal joint maintenance. Because of the striking similarity of osteoarthritis in humans and mice, the Mig-6 mutant mouse should provide a useful animal model for studying the mechanism of this disease and for testing drugs or therapies for treating osteoarthritis.
REVIEW OF STUDIES CONCERNING EFFECTS OF UNBOUND CRUSHED CONCRETE BASES ON PCC PAVEMENT DRAINAGE

Recycled concrete aggregate (RCA) products are sometimes used as replacements for virgin aggregate products in concrete pavement structures. Recent concerns have centered on the deposit of RCA-associated fines and precipitate suspected of reducing the drainage capacity of RCA base layers and associated drainage systems. Environmental concerns have focused on the relatively high pH of the effluent produced by untreated RCA base layers. Several studies have examined these concerns and others; the results of some of these studies have not been published or publicized. The most relevant of these studies are summarized herein. These research efforts demonstrate that calcium-based compounds are present in most recycled concrete aggregates in quantities sufficient to be leached and precipitated in the presence of carbon dioxide. Precipitate potential appears to be related to the amount of freshly exposed cement paste surface. Thus, selective grading or blending with natural aggregates can reduce, but not eliminate, precipitate problems. It was also noted that insoluble, noncarbonate residue makes up a major portion of the materials found in and around pavement drainage systems. Washing the RCA products before using them in foundation layers appears to reduce the potential for accumulation of dust and other fines in the drainage system, but probably has little effect on precipitate potential. Field studies have shown that precipitate and insoluble materials can significantly reduce the permittivity of typical drainage fabrics but that attention to drainage design details can minimize the effects of these materials on pavement drainage.
Personal networks and the incomes of men and women in the United States: Do personal networks provide higher returns for men or women?

Abstract Despite the many studies focusing on the relationship between social networks and labor market outcomes, few have examined differences in returns to personal networks by gender. Informed by the Social Resources Theory, this study tests whether various types of employment job search networks provide greater returns for males or females. Of the few studies examining gender differences, some find that the benefits of social networks are specific to males; others maintain that they also extend to females, and others argue that the benefits are greater for females than males. There are several limitations of the studies focusing on gender and social networks within the labor market. Such studies have not employed nationally representative datasets. They also neglect important distinctions between various types of personal networks. In this study, these limitations are rectified. A nationally representative dataset, the 2002 General Social Survey, is employed to address how personal networks operate for men and women within the US labor market. Additionally, various types of personal networks are employed to enable a more nuanced approach than previous research. The study provides evidence that social networks provide higher returns to women than men, as women receive returns from their networks while men do not.
Polymer brushes by living anionic surface initiated polymerization on flat silicon (SiOx) and gold surfaces: Homopolymers and block copolymers

The formation of homopolymer and block copolymer brushes grafted from Au and Si (SiOx) surfaces via living anionic surface-initiated polymerization (LASIP) is described. The initiator precursor 1,1-diphenylethylene (DPE) was functionalized with alkylsilane or alkylthiol and grafted onto planar Si wafer and Au surfaces, respectively, by self-assembled monolayer techniques. n-BuLi was used to activate the DPE initiator for anionic polymerization of monomers at the interface. A high-vacuum reactor was used for polymerization at surfaces under anhydrous solution conditions. By a careful sequence of monomer introduction, reaction, and termination, homopolymer and block copolymer tethered polymer brushes were obtained. The grafted polymer chains were investigated using surface sensitive techniques such as ellipsometry, contact angle measurements, atomic force microscopy, Fourier transform infrared spectroscopy, surface plasmon spectroscopy, and X-ray photoelectron spectroscopy. The importance of activation of t...
Functional topography of the cerebellum for motor and cognitive tasks: An fMRI study

Anatomical, clinical and imaging findings suggest that the cerebellum is engaged in cognitive and affective functions as well as motor control. Evidence from converging modalities also indicates that there is a functional topography in the human cerebellum for overt control of movement vs. higher functions, such that the cerebellum can be divided into zones depending on connectivity with sensorimotor vs. multimodal association cortices. Using functional MRI, we show that regions active during overt movement differ from those involved in higher-level language, spatial processing and working memory tasks. Nine healthy participants each completed five tasks in order to determine the relative activation patterns for the different paradigms. Right-handed finger-tapping activated right cerebellar lobules IV-V and VIII, consistent with descriptions of the cerebellar homunculi. Verb generation engaged right cerebellar lobules VI-Crus I and a second cluster in lobules VIIB-VIIIA. Mental rotation activation peaks were localized to medial left cerebellar lobule VII (Crus II). A 2-back working memory task activated bilateral regions of lobules VI-VII. Viewing arousing vs. neutral images did not reliably activate the cerebellum or cerebral limbic areas in this study. The cerebellar functional topography identified in this study reflects the involvement of different cerebro-cerebellar circuits depending on the demands of the task being performed: overt movement activated sensorimotor cortices along with contralateral cerebellar lobules IV-V and VIII, whereas more cognitively demanding tasks engaged prefrontal and parietal cortices along with cerebellar lobules VI and VII. These findings provide further support for a cerebellar role in both motor and cognitive tasks, and better establish the existence of functional subregions in the cerebellum. Future studies are needed to determine the exact contribution of the cerebellum - and different cerebro-cerebellar circuits - to task performance.
Rapid Synthesis of MFI Zeolite Nanocrystals

A rapid synthesis procedure for nonagglomerated silicalite nanocrystals has been developed. This was achieved by concentrating the precursor sol before 10−12 h of aging at 80 °C, followed by hydrothermal synthesis at 175 °C for 90 min. The high silica concentration in the concentrated sol accelerated the aggregation of primary units that were present early in the system. Thus, little silica nutrients were left for growth when the secondary particles were converted to zeolite during hydrothermal reaction. As a result, fully dispersible nanocrystals were obtained within a day instead of weeks as reported previously. The aggregation of primary units during the 80 °C aging process as well as the conversion of these aggregates into zeolite has been followed by DLS, XRD, and FTIR. In light of the new results, the nucleation and growth mechanisms of MFI zeolite that have been under debate in the literature were reexamined.
High‐resolution observations of naturally enhanced ion acoustic lines and accompanying auroral fine structures

[1] We present observations of naturally enhanced ion acoustic lines (NEIALs) from a ground-based campaign, combining high-resolution auroral imaging with raw voltage samples from the Poker Flat Incoherent Scatter Radar. We achieved maximum time resolution (∼12 ms) by employing a single beam position. Four distinct events were identified, constituting the first common-volume imager/NEIAL observations in this mode. All were associated with auroral fine structures, were short-lived, and occurred on the boundaries of dynamic, luminous features. Their presence provides further insight into in situ processes, such as enhanced wave activity, that are otherwise unobservable using ground-based instrumentation. Combined high-resolution optical and radar observations reveal the temporal development of NEIALs in relation to the dynamic auroral fine structures present. These observations indicate that NEIALs manifest with timescales of less than 50 to 100 ms, providing a specific constraint for the modeling of their generation mechanisms.
Turnover of Certified Nursing Assistants: A Major Problem for Long-term Care Facilities

The increasing number of aging Americans who will need long-term care, coupled with the need to keep this care affordable, represents a formidable challenge to the healthcare system. Some response must be made to address what will soon become immediate need. A significant part of the approach to this problem lies in making long-term care as efficient, cost effective, and affordable as possible. Reducing turnover of certified nursing assistants (CNAs) will help achieve these goals. This article discusses the extent, implications, and causes of this turnover and puts forth a program to correct the problem.
Cadmium-binding proteins from blue crabs (Callinectes sapidus) environmentally exposed to cadmium

Two heat-stable (90/sup 0/C) cadmium-binding proteins were isolated from the hepatopancreas of Hudson River blue crabs (Callinectes sapidus) by Sephadex G-75 gel filtration chromatography. These proteins have molecular weights of 10,600 and 9,400, and ultraviolet absorbance ratios at 250/280 nm of 12.4 and 5.4, respectively. Repeated freezing and thawing and prolonged (3-6 weeks) storage resulted in protein degradation or loss of Cd-binding activity. These proteins were induced by laboratory injection of CdCl/sub 2/ in blue crabs from pristine (Chesapeake Bay) areas; however, injection of CdCl/sub 2/ into Hudson River animals yielded anomalous chromatography profiles. Cadmium-binding proteins were also identified in blue crab thoracic muscle and gill. The possibility is discussed that these proteins are a type of metallothionein and could contribute to the human toxicity of this cadmium-contaminated edible crustacean.
MAGNITUDE OF STRESS REPORTED BY BASKETBALL REFEREES

723 basketball referees responded to a survey that assessed stress related to officiating. Mean reported ratings were between “very little” and “moderate amount”; only 4% reported high stress. Results are consistent with other accounts, suggesting that most sport officials experience low occupational stress.
Improving satellite orbit solution using double-differenced GPS carrier phase in kinematic mode

The limit of orbit accuracy associated with processing the ionospheric-free double-differenced (DD) GPS carrier phase observable in pure kinematic mode is investigated. The kinematic orbit determination problem becomes unobservable when the satellite positions at all epochs and all of the DD ambiguities are estimated simultaneously without any constraints. Although searching for some of the DD ambiguities can make the problem observable, this is not practical when the DD ambiguities are not integers. However, if a reasonably accurate a priori satellite orbit solution is available, epoch-by-epoch satellite positions and the DD ambiguities can be estimated by constraining a geometrically strong DD pass. The technique was demonstrated with TOPEX GPS data, which gave a final radial RMS orbit accuracy of 4 cm with respect to a fully dynamic solution.
Toward a theory of in-network computation in wireless sensor networks

Sensor networks are not just data networks with sensors being the sources of data. Rather, they are often developed and deployed for a specific application, and the entire network operation is accordingly geared toward satisfying this application. For overall system efficiency, it may be necessary for nodes to perform computations on data, as opposed to simply originating or forwarding data. Thus, the entire network can be viewed as performing an application-specific distributed computation. The topic of this article is to survey some lines of research that may be useful in developing a theory of in-network computation, which aims to elucidate how a wireless sensor network should efficiently perform such distributed computation. We review several existing approaches to computation problems in network settings, with a particular emphasis on the communication aspect of computation. We begin by studying the basic two-party communication complexity model and how to optimally compute functions of distributed inputs in this setting. We proceed to larger multihop networks, and study how block computation and function structure can be exploited to provide greater computational throughput. We then consider distributed computation problems in networks subject to noise. Finally, we review some randomized gossip-based approaches to computing aggregate functions in networks. These are diverse approaches spanning many different research communities, but together may find a role in the development of a more substantial theoretical foundation for sensor networks.
Adherence to Antiretroviral Therapy Among HIV-Infected Methadone Patients: Effect of Ongoing Illicit Drug Use*

Methadone maintenance patients infected with human immunodeficiency virus (HIV) currently receiving antiretroviral therapy had HIV RNA testing and were surveyed regarding their adherence to their t...
Exact And Approximate Inversion of Plane-layered Isotropic And Anisotropic Elastic Media By Layer Stripping

In ill-posed PE problems, the parameter values expected from a priori information may be used for the enhancement of the estimation results. In this paper, it is shown that the uncertainty intervals of these expected values should be taken into account as well. By doing this, the estimation results can be substantially improved, i.e., the total model error is reduced. Note that weighting in well-posed problems (unique estimation results) has no effect on the estimator (Van der Made, 1984). The examples shown in this paper are very simple. More complex cases will be shown at the presentation of this paper. It will be shown that also in these cases weighted estimation yields substantially improved results over unweighted estimation.
Estimating the number of Jews in the service area of the Jewish Federation of Palm Beach County: Lessons for all Jewish Communities

Many American Jews, perhaps the majority, identify themselves as being "ethnically" Jewish. That is, they view themselves as being of Jewish origin, irrespective of synagogue membership or religious observance levels. In spite of tbi.% the United States Bureau of the Census traditionally has viewed Jews as a religious group. Due in part to the doctrine of the separation of ch~ch and state, data on religious preference has not been collected by the US Census (with the exception of a study conducted in March 1957). A major demographic study with national supervision was completed in 1971 (the National Jewish Population Study-NJPS Massarik and Che~ldn, 1973), resulting in estimates of the Jewish population for the country as a whole, for various regions, and for a number of major metropohtan areas. Such a study may be repeated in 1990 (Goldstein et al., 1988). More than 50 American Jewish commlmities have commi.~sioned demographic studies since 1975, representing more than 75% of American Jews (Che~idn, 1982: 11; Kosmin, 1986: 25). While such studies prOduce a wealth of data on demographic, geographic, and religious dimensions as wen as profiles of organizational and philanthropic behavior, the most sought after and most published result is the estimate of the Jewish population in the service area of the Federation commi.c~ioning the study. In some cases, the numbers are perceived to have significant impact on Federation funding decisions and may lead to considerable controversy (Ritterband and Cohen, 1984). A variety of methods have been used to derive estimates of the Jewish population of particular dries. These include procedures
Mathematical notions in preliterate societies

Many preliterate societies show considerable mathematical development. It is not unusual to encounter numeral systems going up to the hundreds of thousands or higher and to encounter some arithmetic ability. Many geometric notions are present, including simple forms like circles, lines, rectangles and parallelograms, and triangles, Other shapes and curves occur with less frequency. Some simpler geometric constructions are carried out, and perhaps some properties of similar right triangles are known. Logical reasoning shows up in kinship relationships and in some games of strategy. People seem to develop basic mathematical notions largely in response to what they consider important aspects of life. Large numbers come up when people need to count higher, whether counting shells used as money or yams harvested and stored or animals. More precise geometric constructions also enter in only where the society values precision. Part of determining exactly what a society has accomplished mathematically involves finding those aspects of life where the development of mathematical notions was important to the people.
The Islands of Calleja Complex of Rat Basal Forebrain II: Connections of Medium and Large Sized Cells

Abstract The connections of the medium (10–20 μm) and large (20–35 μm) cells of the islands of Calleja Complex (ICC) were studied in the albino rat with anterograde and retrograde transport of horseradish peroxidase (HRP) and fluorescent tracers. The medium and large size cells were found to project to the ipsilateral olfactory tubercle, ventral pallidum, septum, piriform cortex, periamygdaloid cortex, cortical nuclei of the amygdala, ventral endopiriform nucleus, lateral hypothalamic area, Forel's field H, ventral tegmental area, supramammillary complex, and nuclei gemini of the hypothalamus, midline, intralaminar and medial thalamic nuclei, and lateral habenula. Afferents of the ICC appear to include the same nuclei with the exception of the lateral habenula. In addition, the dorsal raphe projects to the ICC. These connections are consistent with the concept that the ICC is a striato-pallidal structure.
New phase function to describe optical scattering within biological tissues

Biological tissues produce high levels of optical scattering in the visible and near-infrared. A phase function is often used to characterize the scattering properties of the media. Henyey- Greenstein's phase function has been widely adopted by researchers in the biomedical optics field. A new scattering phase function is proposed to approximate phase functions strictly derived from Mie scattering theory. The new phase function demonstrates much better agreement with Mie theory than Henyey-Greenstein's phase function. In calculation of light propagation within biological media using the radiative transport equation, the phase function plays an even more important role. Using the new phase function as the integral kernel in the radiative transport equation, an analytical expression for the integral term of the equation is obtained for highly aligned beams. This may lead to a semi-analytical solution to the time- dependent radiative transport equation for time-resolved spectroscopy.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Pyridazines. IV. The synthesis and some reactions of acetylpyridazines

Two 3-acetylpyridazines have been prepared. N-Oxidation of 3-acetylpyridazine (6) gave only 3-acetylpyridazine 1-oxide (7). During the N-oxidation of 3-acetyl-6-methoxypyridazine (10), three primary products, namely, 3-acetyl-6-methoxypyridazine 1-oxide (12), 3-acetyl-6-methoxy-pyridazine 2-oxide (13), 3-acetylpyridazin-6-one (14) and an artifact, 3-methoxypyridazine 1-oxide (15) were obtained. Furthermore, it has been shown that 3-methoxypyridazine 1-oxide (15) can be obtained in quantitative yield by treatment of 3-acetyl-6-methoxypyridazine 2-oxide (13) with dilute sodium hydroxide solution at room temperature. This represents a novel deacylation reaction. Nitration of 3-acetylpyridazine 1-oxide, (7) gave 3,4-bis(3′-pyridazinoyl)furoxan 1′,1′-dioxide (19) rather than a simple nitration product. 3-Acetyl-pyridazine (6) and 3-acetyl-6-methoxypyridazine (10) also gave furoxans (22 and 23) upon nitration.
The phylogeny of enkephalins, speculations on the origins of opioid precursors

Enkephalins, dynorphins and β-endorphin are endogenous opiate-like substances that are differentially distributed among vertebrate taxa. Enkephalins have the widest distribution, and the proenkephalin gene would appear to represent the ancestral opioid gene. This review will consider the following hypothesis: the evolution of the opioids occurred as a result of two duplications of the proenkephalin gene. In this hypothesis, the first duplication event would have given rise to the proopiomelanocortin gene, the precursor for β-endorphin, and the second duplication event would have given rise to the prodynorphin gene.
Efficient intramolecular excited-state energy transfer in pyrenes–fullerene macromolecule

The fluorescence of pyrene species covalently linked with a methanofullerene is nearly completely quenched due to efficient excited-state energy transfer to the fullerene cage, resulting in the population of the emissive fullerene excited state. The quenching is largely static in nature, consistent with the computational result that the pyrene moieties are close to the fullerene cage. The yield for the excited-state pyrene to fullerene energy transfer is determined.
The role of polar groups in the interaction of dipalmitoyl phosphatidylcholine with chlorophyll a in monolayers

Abstract Investigation of pure dipalmitoyl phosphatidylcholine (DPPC) monolayers suggests that interactions between DPPC head groups are important to the surface behavior of these molecules. Surface pressure-area studies of mixed monolayers of DPPC with chlorophyll α or β-carotene emphasize the importance of interactions between polar groups in chlorophyll α and the head group of DPPC. These interactions may play an important role in the transport of ions or electrons through membranes.
Urea and protein metabolism in burned children: Effect of dietary protein intake

Abstract The response of urea metabolic kinetics, the rate of whole-body protein breakdown, and muscle and skin protein synthesis rates to dietary protein intake (1.15 to 2.92 g/kg/d) was assessed in children with 20% to 40% total body surface area burn injury using a primed continuous infusion of 15 N 2 -urea and l- 13 C 6 -phenylalanine. Plasma urea concentration, production, and excretion rates increased with dietary protein intake without evidence of approaching maximum plateau values. There was no consistent evidence of urea recycling in these subjects (urea production=excretion) at any level of protein intake. The rate of appearance (Ra) of phenylalanine (an index of whole-body protein breakdown) and rate of muscle protein synthesis were independent of dietary protein, whereas there was a significant increase in skin protein synthesis with higher protein intake. We conclude that there seems to be little benefit of high protein intake on whole-body protein breakdown and muscle protein synthesis rates in these burn patients, although high-protein diets may enhance wound healing.
A familiar motif in a new context: the catalytic mechanism of hydroxyisourate hydrolase.

Hydroxyisourate hydrolase is a recently discovered enzyme that participates in the ureide pathway in soybeans. Its role is to catalyze the hydrolysis of 5-hydroxyisourate, the product of the urate oxidase reaction. There is extensive sequence homology between hydroxyisourate hydrolase and retaining glycosidases; in particular, the conserved active site glutamate residues found in retaining glycosidases are present in hydroxyisourate hydrolase as Glu 199 and Glu 408. However, experimental investigation of their roles, as well as the catalytic mechanism of the enzyme, have been precluded by the instability of 5-hydroxyisourate. Here, we report that diaminouracil serves as a slow, alternative substrate and can be used to investigate catalysis by hydroxyisourate hydrolase. The activity of the E199A protein was reduced 400-fold relative to wild-type, and no activity could be detected with the E408A mutant. Steady-state kinetic studies of the wild-type protein revealed that the pH-dependence of V m a x and V/K describe bell-shaped curves, consistent with the hypothesis that catalysis requires two ionizable groups in opposite protonation states. Addition of 100 mM azide accelerated the reaction catalyzed by the wild-type enzyme 8-fold and the E199A mutant 20-fold but had no effect on the E408A mutant. These data suggest that Glu 408 acts as a nucleophile toward the substrate forming a covalent anhydride intermediate, and Glu 199 facilitates formation of the intermediate by serving as a general acid and then activates water for hydrolysis of the intermediate. Thus, the mechanism of hydroxyisourate hydrolase is strikingly similar to that of retaining glycosidases, even though it catalyzes hydrolysis of an amide bond.
Parametric Study of Aerocapture for Missions to Venus

A parametric study has been conducted of aerocapture for missions to Venus, examining the entry corridor width as a function of entry velocity, vehicle aerodynamics, and atmospheric density dispersions. The corridor width is found to exceed 1 deg for low lift-to-drag configurations such as an Apollo capsule. For a vehicle with a ballistic coefficient of 78 kg/m 2 and an entry speed of 12 km/s, preliminary calculations indicate that midcorridor trajectories will produce peak stagnation-point heating rates approximately 30% higher than those encountered on Apollo lunar return. Trajectories with modest deceleration loads (under 20 g) and reasonable postaerocapture propulsive requirements were readily identified. Aerocapture is found to merit further study for its potential application on future missions to Venus.
Current Steering with Partial Tripolar Stimulation Mode in Cochlear Implants

The large spread of excitation is a major cause of poor spectral resolution for cochlear implant (CI) users. Partial tripolar (pTP) mode has been proposed to reduce current spread by returning an equally distributed fraction (0.5×σ) of current to two flanking electrodes and the rest to an extra-cochlear ground. This study tested the efficacy of incorporating current steering into pTP mode to add spectral channels. Different proportions of current [α×σ and (1−α)×σ] were returned to the basal and apical flanking electrodes respectively to shape the electric field. Loudness and pitch perception with α from 0 to 1 in steps of 0.1 was simulated with a computational model of CI stimulation and tested on the apical, middle, and basal electrodes of six CI subjects. The highest σ allowing for full loudness growth within the implant compliance limit was chosen for each main electrode. Pitch ranking was measured between pairs of loudness-balanced steered pTP stimuli with an α interval of 0.1 at the most comfortable level. Results demonstrated that steered pTP stimuli with α around 0.5 required more current to achieve equal loudness than those with α around 0 or 1, maybe due to more focused excitation patterns. Subjects usually perceived decreasing pitches as α increased from 0 to 1, somewhat consistent with the apical shift of the center of gravity of excitation pattern in the model. Pitch discrimination was not better with α around 0.5 than with α around 0 or 1, except for some subjects and electrodes. For three subjects with better pitch discrimination, about half of the pitch ranges of two adjacent main electrodes overlapped with each other in steered pTP mode. These results suggest that current steering with focused pTP mode may improve spectral resolution and pitch perception with CIs.
Phosphatidate phosphohydrolase in the fat body of Hyalophora cecropia

Abstract Potent phosphatidate phosphohydrolase activity was associated with particulate, sub-cellular fractions of Cecropia fat body and flight muscle. The greatest enzymic activity was demonstrated in the microsomal fraction. The fat body phosphatidate phosphohydrolase displayed optimum activity at pH 7·4; 37 to 40°C. The calculated Km value was 0·7 × 10−4 M which is similar to values for vertebrate preparations. The fat body enzyme was inhibited by a series of divalent cations but not by Mg2+ which instead appeared to stimulate enzyme activity. A sulfhydryl inhibitor prevented optimum enzyme action and this effect was completely reversed by reduced glutathione indicating the presence of a necessary thiol group in the enzyme preparation. Enzymic activity was high in chilled pupae, decreased at the beginning of adult development and then increased steadily until adult emergence. No sexual dimorphism in activity was noted.
Cardiac Arrest Following Massive Pulmonary Embolism During Mechanical Declotting of Thrombosed Hemodialysis Fistula: Successful Resuscitation With tPA

Percutaneous declotting of a thrombosed fistula or graft is standard of care and is a safe procedure. Subclinical pulmonary embolism (PE) during this procedure occurs commonly, but symptomatic PE is extremely rare. The authors report a case of declotting-associated massive PE with cardiopulmonary arrest and successful resuscitation. The patient developed a new right-axis deviation and right-bundle branch block. Diagnosis of PE was confirmed with a computed tomography (CT) angiogram, and the patient received tissue plasminogen activator (tPA) and heparin. She required norepinephrine and dobutamine temporarily and was subsequently extubated successfully. Massive PE is a very rare complication of this procedure. Given the grave outcome, the clinical signs and symptoms should be recognized immediately and treatment instituted early.
On the logic of variable rules

In the introduction we stated two frequently encountered a priori arguments against the variable rule methodology and attempted to refute them. The first rejects the variable rule methodology – and by implication any study of comparable data – on the grounds that variable rules govern token frequencies while generative grammar does not countenance token frequencies. We agree that variable rules are not generative rules of a new sort but an entirely different kind of logical object and that generative grammar indeed does not countenance token frequencies. But we are convinced by empirical work conducted within the variable rule paradigm that token frequencies often display clear patterns and that moreover some knowledge of these patterns forms part of the linguistic abilities of speakers. We conclude that, whatever the drawbacks of the variable rule formalism, studies employing variable rules have shown regularities in linguistic behavior that point to a serious lack in the generative paradigm, narrowly defined.A second line of argument against variable rules which we rejected was based on assumptions about human psychology and about probability theory. The assumption that human beings cannot assess probabilities and behave in accord with them in a natural and unconscious manner appears to be supported by no empirical evidence and does not seem to us plausible a priori. Moreover, experimental evidence to the contrary exists. The argument to probability theory was that a speaker would have to have an internal counting device to keep track of the relative frequencies of linguistic variants that he had heard from his own or other lips in order to behave in accordance with variable rules. But this would require a kind of probability theory that would differ in remarkable and unspecified ways from ordinary probability theory, since the paradigmatic empirical examples of the familiar theory, such as coins, dice, decks of cards, and so on, are not possessed of memories.
Pair-breaking mechanisms in superconductor--normal-metal--superconductor junctions

The critical current density J/sub c/ has been measured for superconductor--normal-metal--superconductor (S-N-S ) junctions over a wide range of temperature and composition in order to determine the depairing effects of magnetic impurities. Junctions, which are in a sandwich geometry with the N layer typically 600 nm thick, show well-defined diffraction patterns indicating that the junctions are of high quality. Below 4.2 K, the temperature dependence of J/sub c/ is found to follow a modified bridge theory based on the work of Makeev et al. (Fiz. Nizk. Temp. 6, 429 (1980) ( Sov. J. Low Temp. Phys. 6, 203 (1980)) ). In this range, the coherence length and order parameter in the superconductor are essentially independent of temperature, and so it is reasonable that the bridge and sandwich geometry results are similar. As the temperature approaches the transition temperature (T/sub c/S) of the superconductor, J/sub c/ was found to be proportional to (1-T/T/sub c/S)/sup 2/ as predicted by de Gennes.
Measurement of Instantaneous Blood Flow Velocity and Pressure in Conscious Man with a Catheter-Tip Velocity Probe

Twenty-three patients were investigated during diagnostic right and left cardiac catheterization with an electromagnetic catheter-tip velocity probe. The catheter contained a pressure lumen for sim...
Statistical mechanics and invariant perception.

The problem of discrimination among ensembles of images generated by distortions of a prototype and the addition of noise is considered. As the noise level is increased, the discrimination task becomes qualitatively more difficult in that optimal discrimination requires the computation of increasingly longer-ranged correlations, or the solution of increasingly difficult optimization problems. These results suggest the use of such image ensembles in probing the computational abilities of the human visual system, and possible theoretical implications of such experiments are discussed.