cssi/SciSciGPT-SciSciNet huggingface dataset:
I. Kinematik der Schwingungen

Eine Schwingung im allgemeinen Sinn ist eine periodische Bewegung, d. h. eine Bewegung, die sich mit all ihren Einzelheiten nach einem bestimmten Zeitintervall T wiederholt. Dies Zeitintervall T wird die „Periodendauer“ oder kurz die „Periode“ der Schwingung genannt. Tragt man die Auslenkung x gegen die Zeit t auf, so erhalt man also eine periodische Kurve, die im einzelnen beliebig unregelmasig sein kann. Abb. 1a zeigt als Beispiel die an einem Punkt der Grundplatte einer Dampfturbine in zeitlicher Folge beobachteten Verschiebungen.
A theory for rule triggering systems

We define and study the family of RTS's, each appearing in the form of a relational database extended with a set of production-like rules with forward-chained operational semantics.
Mass spectrometric study on the mechanism of D-glucose 6-phosphate-L-myo-inositol 1-phosphate cyclase.

Abstract d-Glucose-6-P-do and d-glucose-6-P-d7 have been separately and simultaneously incubated with a phosphohexoisomerase-free preparation of d-glucose-6-P-myo-inositol-1-P cyclase from bovine testis. The l-myo-inositol-1-P-d0 and l-myo-inositol-1-P-d6 produced by the reaction were completely trimethylsilylated and analyzed by combined gas chromatography and mass spectrometry. The absence of any crossover of label from deuterated to nondeuterated product in the case of the simultaneous incubation is given as evidence that all of the intermediate products in this DPN+-mediated cyclization are enzyme-bound during the course of the reaction. Direct evidence is given for the first time that the phosphate-bearing carbon atom in d-glucose-6-P is the same atom which bears the phosphate in l-myo-inositol-1-P.
Microbiologic and echocardiographic pitfalls in diagnosis of native valve Staphylococcus aureus acute bacterial endocarditis (ABE): a clinical approach

The diagnosis of Staphylcocccus aureus acute bacterial endocarditis (ABE) is based on microbiologic and echocardiographic findings not on subacute bacterial endocarditis (SBE) criteria.1,2 S. aureu...
Mechanics of BCC and FCC hollow-sphere foams

Hollow-sphere foams provide an alternative microstructure for low-density metal structures with the potential for improved properties. In a recent companion paper, the mechanical properties of hollow-sphere foams with simple cubic packing (SC) were shown to be close to the theoretical values for closed-cell foams and well above the measured modulus and strength of metallic closed-cell foams. Here, we analyze the elastic moduli and initial yield strength of body-centered cubic and face-centered cubic (FCC) packings of hollow-sphere foams. In general, the FCC packing gives the highest values of moduli and strengths.
Bilateral teleoperation: An historical survey

This survey addresses the subject of bilateral teleoperation, a research stream with more than 50 years of history and one that continues to be a fertile ground for theoretical exploration and many applications. We focus on the control theoretic approaches that have been developed to address inherent control problems such as delays and information loss. Exposure to several concurrent applications is provided, and possible future trends are outlined.
A monochromatic light system for the analytical ultracentrifuge

Abstract A monochromatic light system employing a xenon-mercury light source and a Schoeffel quartz prism monochromator is described for the absorption system of the Spinco analytical ultracentrifuge. By using conventional photographic techniques, the system may be employed from 235 to 700 mμ. Applications of the system are illustrated and discussed.
Morbidity in a population of low-income, female users of MDMA and other drugs.

Few previous studies have reported on the overall health of drug-using women. To investigate this, 696 low-income women aged 18–31 were recruited in a cross-sectional study from gynecological care clinics in Texas between 2001 and 2003. Compared to exclusive marijuana users and non–drug users, women who used MDMA and those who used other illicit drugs but not MDMA reported more gynecological conditions, medical conditions, depressive symptoms, and physical somatic complaints. We concluded that young, low-income women who used more than one illicit drug experience significantly more physical and psychological morbidity. Generalization of this study results may be limited to young women with low income but not to other populations.
Recoverin negative photoreceptor cells.

Recoverin, a calcium-binding protein, is unique with respect to its cellular regulation. It is present in retinal rods, cones, cone bipolar cells, and in a rare population of cells in the ganglion cell layer. Inappropriate turn-on or turn-off of recoverin expression has been reported both in small cell lung carcinoma cells from patients with cancer-associated retinopathy (Matsusara et al. [1996] Br. J. Cancer 74:1419-1422; Adamus et al. [1998] J. Autoimmun. 11: 523-533; Ohguro et al. [1999] Invest. Ophthalmol. Vis. Sci. 40:82-89) and in cultured retinal neurons (McGinnis et al. [1999] J. Neursci. Res. 55:252-260). In a recent report using double labeling immunofluorescence microscopy methods with antibodies against either rhodopsin and recoverin or arrestin and recoverin, two unique cell phenotypes, rhodopsin-positive and recoverin-negative, and arrestin-positive, and recoverin-negative were observed in vitro. These two unique cell types could be nonphotoreceptor cells in which rhodopsin and arrestin are inappropriately turned on or they are photoreceptor cells in which the recoverin gene is inappropriately turned off. In this study, multiple antibodies were used to study, on a single-cell basis, whether the photoreceptor cell-specific marker, rhodopsin, is inappropriately expressed in nonphotoreceptor cells in our retinal neuronal culture system. We also examined the hypothesis that the two unique cell phenotypes represent the same population of cells. A triple labeling method has been established to visualize recoverin, rhodopsin, and arrestin protein expression simultaneously in cultured retinal neurons. Our data clearly and directly demonstrate that the previously described unique cell phenotypes are the same population of cells, rod photoreceptors. The existence of recoverin-negative photoreceptors demonstrates that the recoverin gene can be regulated independently of other photoreceptor cell-specific proteins and suggests that this primary cell culture may be useful as a model system for investigating the illicit expression of the recoverin gene in cancer associated retinopathy.
Microstructures of Si surface layers implanted with Cu

Microstructures of Si ion-implanted with Cu have been characterized by TEM after annealing. For 1.2 at.%, the Cu is trapped at planar defects, but for 10 at.%, {eta}-Cu{sub 3}Si forms and Cu diffuses at its equilibrium solubility. These observations allow proper evaluation of the binding energies of Cu to previously formed internal cavities (2.2 eV) and {eta}-Cu{sub 3}Si (1.7 eV). The 10 at.% Cu layer promotes oxidation of Si catalyzed by {eta}-Cu{sub 3}Si. The microstructures also indicate that Si implanted with {approximately}2 at.% Cu reforms epitaxially with embedded defects after 8 hr at 700C, but for {approximately}10 at.% Cu, epitaxy is not recovered after 6 hours at 600C.
How much of the decline in sound recording sales is due to file-sharing?

Although most studies of file-sharing have concluded that file-sharing has decreased record sales, the extent of the decreased sales often seems uneven. This paper demonstrates that the results are more uniform than previously understood once a consistent metric is used to provide easy comparability across studies. This paper uses the percent of the decline in record sales that is due to file-sharing as a metric to translate the results of the literature into a common framework and then summarizes those results. What has not been previously noted is that the estimates from most studies imply that the impact of file-sharing was sufficient to have caused the entire decline in record sales that occurred from the advent of Napster up to about 2005. A smaller number of studies using post-2005 data indicate that the shift to digital formats may also have contributed to the sales decline that continued after 2005.
Acute effects of suction retraction on atrial hemodynamics and histology

Objectives In minimally invasive and robotic mitral valve surgery, a blade retractor is used to elevate the left atrial roof, which often distorts tissue and impairs visualization. We tested the hemodynamic and histologic changes of intra-atrial suction, using a new suction retractor that may improve stabilization and visualization. Methods Swine were divided into 3 equal (n = 4) groups: blade retractor, suction retractor, and arrested heart control. Left atrial ultrasonic crystals were used to record ejection fractions. After cardioplegic arrest, the atrium was opened and sampled for preretractor histology. Retractors remained in place for 1 hour, followed by postretractor histologic sampling. Controls were crossclamped for an equivalent time and postarrest histologic data obtained. Animals were weaned from bypass, data were collected for 4 hours, and postsacrifice atrial histologic samples were obtained. Results The main effect due to treatment was not statistically significant ( P = .52) between the 3 groups, with the 4-hour average ejection fraction for blade retractor, suction retractor, and control being statistically equivalent at 33.3% ± 8.3, 35.3% ± 12.1, and 40.8% ± 9.9 (mean ± standard deviation), respectively. Histology showed equivalent amounts of myocyte fragmentation, interstitial edema, eosinophilia, and wavy fibers between blade retraction and suction retraction, while the latter showed slightly increased amounts of hemorrhage. Conclusions Atrial endocardial suction retraction appears to be safe with no acute changes in the left atrial ejection fraction or significant acute histologic differences, compared to blade retraction. Furthermore, intra-atrial suction may be applicable to procedures other than minimally invasive and robotic mitral valve repair for providing improved stabilization.
Anaphase is initiated by proteolysis rather than by the inactivation of maturation-promoting factor

We have used frog egg extracts that assemble mitotic spindles to identify the event that triggers sister chromatid separation. Adding a nondegradable form of cyclin B prevents maturation-promoting factor (MPF) inactivation but does not block sister chromatid separation, showing that MPF inactivation is not needed to initiate anaphase. In contrast, adding an N-terminal fragment of cyclin, which acts as a specific competitor for cyclin degradation, produces a dose-dependent delay in MPF inactivation and sister chromatid separation. Methylated ubiquitin, which inhibits ubiquitin-mediated proteolysis, also delays sister chromatid separation, suggesting that ubiquitin-mediated proteolysis is necessary to initiate anaphase. The N-terminal cyclin fragment inhibits chromosome separation even in extracts that contain only nondegradable forms of cyclin, suggesting that proteins other than the known cyclins must be degraded to dissolve the linkage between sister chromatids.
Ability of multiangle remote sensing observations to identify and distinguish mineral dust types: 2. Sensitivity over dark water

[1] We explore the ability of multiangle, multispectral measurements, such as those from the Multiangle Imaging SpectroRadiometer (MISR), to retrieve mineral dust properties. We first investigate MISR sensitivity theoretically, to a selection of medium-mode particle shapes, to single-scattering albedo (SSA), and to the ratio of medium- to large-mode aerosol optical thickness (AOT). Favorable, but not ideal, viewing conditions over dark water are assumed, and new dust optical models are adopted. This study shows sensitivity to differences in the angular spectral signals of medium-mode shapes when column midvisible AOT is greater than ∼0.15 for components contributing 15–20% or more to the AOT. MISR-like retrievals can also distinguish strongly absorbing (red channel SSA ∼ 0.94) from less absorbing (SSA ∼ 0.98–0.99) dust particles. Bimodal size sensitivity results suggest that MISR can distinguish the ratio of medium to larger components in roughly 20% midvisible AOT increments. For five Saharan dust field events over homogeneous, cloud-free dark water near the Cape Verde AERONET station, MISR research retrieval results were dominated by weakly absorbing medium grains. MISR-retrieved spectral AOT was within 0.02 of the Aerosol Robotic Network (AERONET), except for one spatially heterogeneous AOT > 1 case, and one where AERONET retrieved a significant component <0.1 μm in radius. In two cases where AERONET ran retrievals assuming nonspherical (spheroidal) particles, SSA fell within 0.02 of MISR. When included in the MISR Standard Aerosol Retrieval Algorithm, the new dust optical models improve both the coverage of successful retrievals and the spectral AOT agreement with near-coincident AERONET measurements. Large-mode dust models and available field constraint limitations are being addressed in continuing work.
Synthesis and characterization of aqueous colloidal dispersions of poly(vinyl alcohol)/polyaniline particles

Abstract Colloidal polyaniline has been prepared in acidic aqueous media by a modified chemical polymerization of aniline in the presence of a tailor-made polymeric surfactant. The surfactant which acts as a steric stabilizer used in this study is derivatized poly(vinyl alcohol-co-vinyl acetate). This surfactant contains pendant aniline units which participate in the aniline polymerization, resulting in the formation of sterically-stabilized polyaniline particles which have a non-spherical “rice-grain” morphology. It is shown that this novel form of polyaniline is more processable than the bulk powder that is normally obtained from a conventional chemical synthesis. The solid-state conductivity of solution-cast films or compressed pellets of these dispersions is surprisingly high (≃1 S/cm), despite the presence of the insulating outer layer of chemically-grafted stabilizer. We have characterized these polyaniline colloids by a wide range of techniques including electron microscopy, cyclic voltammetry and ...
Territories, corridors, and networks: A biological model for the premodern state

When depicted on maps as homogenous territorial wholes, ancient states are visually summarized as static entities in a way that conceals the highly fluid dynamics of polity formation, maintenance, and growth. Models derived from studies of animal behavior show that “territory” does not consist of an undifferentiated use of the landscape. Instead, the concept of territory can be parsed into a series of resource-rich nodes linked by corridors of access, surrounded by unutilized regions and boundaries marked at points of competition. Ancient human groups also can be analyzed as having perceived and occupied landscapes through strategies of flexible networks in which nodes and corridors were surrounded by unutilized spaces around which boundaries were selectively identified and defended. This strategy is identifiable in human social groups at different levels of complexity ranging from hunter-gatherers through ancient chiefdoms and states. © 2007 Wiley Periodicals, Inc. Complexity 12: 28–35, 2007
Lentiviral latency in peripheral CD4+ T cells isolated from feline immunodeficiency virus-infected cats during the asymptomatic phase is not associated with hypermethylation of the proviral promoter.

Abstract Lentiviral latency remains a principal obstacle to curative AIDS therapy. Transcriptional repression and latency permits lentiviruses to evade host immune responses and antiretroviral drugs. We have established a model of peripheral CD4+ T cell lentiviral latency in cats experimentally infected with feline immunodeficiency virus (FIV). Multiple mechanisms of lentiviral transcriptional repression have been proposed including epigenetic mechanisms resulting in promoter hypermethylation and/or chromatin condensation. Methylation of promoter-associated cytosines in the cytosine-guanine dinucleotide (CpG) has been associated with transcriptional repression in both eukaryotic promoters and integrated retroviral genomes. Using methylcytosine mapping, we examined the CpG methylation patterns in both the 5′ and 3′ long terminal repeats (LTR) of the FIV provirus in peripheral blood mononuclear cells, monocytes and CD4+ T cells isolated during the acute and asymptomatic phases of infection. Here we report no evidence that proviral promoter hypermethylation is associated with lentiviral latency in peripheral CD4+ T cells and monocytes obtained from experimentally FIV-infected cats.
Security enhanced mobile agents

This paper describes a security model for mobile agent based systems. The model defines the notion of a security-enhanced agent and outlines security management components in agent platform bases and considers secure migration of agents from one base to another. The security enhanced agent carries a passport that contains its security credentials and some related security code. Then we describe how authentication, integrity and confidentiality, and access control are achieved using the agent’s passport and the security infrastructure in the agent bases. We also consider the types of access control policies that can be specified using the security enhanced agents and the policy base in the agent platforms. We discuss the application of the security model in roaming mobile agents and consider a simple scenario involving security auditing in networks.
EFFECT OF DEUTERIUM OXIDE ON THE GROWTH OF PEPPERMINT. II. HISTOLOGICAL EFFECTS.

Representative sections of leaf, stem, and root of peppermint plants grown in 70 per cent D 2 O nutrient were examined microscopically; comparison was made of the significant histological features with sections from plants grown in an aqueous nutrient. The major effect of deuterium on the growth of peppermint appears to be inhibition of cell divisions. Parenchyma cells are enlarged and vascular tissue appears to be reduced in the deuteriated plants. In general, the effects were more pronounced in growing tissues than in tissue exposed to deuterium after differentiation had occurred.
Improvement Model of MC-CDMA in Frequency Selective Fading Channel

In this paper, a phase matrix rotation model was proposed to improve the performance of Multicarrier-Code Division Multiple Access (MC-CDMA) based Fast Fourier Transform (FFT) under the Additive White Gaussian Noise (AWGN) channel and frequency selective fading channel. This model is used to reduce the effect of multipath fading. The results extracted by a computer simulation for a single user. Then it compared with the original technique for MC-CDMA based FFT for both systems. As a result, it can be seen from the proposed technique that a high performance improvement was obtained over the conventional MC-CDMA, were the Bit Error Rate (BER) is widely reduced under different channel characteristics for frequency selective fading and the AWGN channel.
Nonphysical Factors That Affect Work Hardening Success: A Retrospective Study

The high cost of health care and limited information regarding the effects of work hardening have prompted a need to further study work hardening programs. The purpose of this study was to determine the success of a work hardening program that included physical, occupational, and psychological therapies, and to determine if there are nonphysical factors associated with successful work hardening. One hundred medical records of injured workers with low back pain and other musculoskeletal disorders were retrospectively reviewed. Factors examined included months of injury, education level, sex, race, presence of an attorney, prior surgery, pain behaviors, smoking, medication use, and diagnosis severity. Seventy-six percent of the subjects successfully completed the program, and 50% of the subjects were returned to work at discharge. Nonphysical factors that limited successful work hardening were presence of pain behaviors (p < .01), attorney representation (p < .01), McAndrews score above 70 (p < .05), and education less than high school (p < .05). The author concludes that the return to work rate for injured workers in this study is comparable to rates of previous studies and that there are nonphysical factors associated with the success of work hardening.
Behavioral evidence for dopaminergic supersensitivity following chronic treatment with methadone or chlorpromazine in the guinea pig.

This study demonstrated the enhancement, as a consequence of prior chronic drug treatment, of two behaviors (stereotyped oral behaviors and open field locomotion) which are thought to depend primarily on the striatel dopamine system. Following a 5-week treatment with methadone (MD), chlorpromazine (CPZ), or saline, the dopamine agonist methamphetamine (MA) elicited more intense stereotypies in the MD and CPZ animals. After chronic treatment with MD, the MA-elicited stereotypies were reduced by an acute dose of MD. Stereotyped oral behaviors elicited by a stressful stimulus (foot shock) were enhanced in the MD animals both during and following chronic drug treatment. MA-elicited open field locomotion, measured 2 weeks following termination of chronic drug treatment, was enhanced in the MD and CPZ animals.
A Mentor and a Role Model: A Tribute to Emilio Gatti

My first year of college at the Politecnico di Milano was 1966, a year of turmoil in colleges wordwide, when the Free Speech Movement started in Berkeley. Students in Italy began acting on their restlessness in late 1967-early 1968 in schools of architecture. The Politecnico di Milano had two branches: architecture and engineering. Engineering students were traditionally more conservative with a slant towards liberal stances in society and life in general. On 5 March 1968, the Politecnico was occupied by architecture students who wanted to radically change the way exams were administered and curricula designed; they also proposed a radically different model for society. The engineering students opposed this political agenda and while agreeing on the occupation of the Politecnico, wished to push for more transparency in the university's administration, for more access to faculty, and for deeper insight into how technology impacted society and industry.
The influence of accumulation on the hall-effect in n-type Hg1−xCdxTe

Abstract The presence of an electron accumulation layer on the surface of n-type Hg1−xCdxTe causes the measured Hall mobility and carrier concentration to be significantly different from the actual bulk values. This discrepancy is not readily apparent in the temperature dependence of the Hall coefficient, RH, as is the case with p-type layers. However, it is observed in the magnetic-field dependence of the RH. The B-field dependence of RH was analyzed to extract the actual concentration and mobility of the bulk and surface carriers in Hg1−xCdxTe layers grown by organometallic vapor phase epitaxy. The bulk parameters thus calculated were verified by passivating the surface of these layers using an anodic sulfide to reduce the concentration of surface electrons.
VALIDATING THE GENERALITY AND PREDICTIVE ABILITY OF UNIFIED RHEOLOGICAL CURVES FOR UNMODIFIED PAVING ASPHALTS

Abstract Fundamental rheological properties of unmodified paving asphalts have been shown to form unified curves when the material’s volumetric flow rate MVR (in cm 3 /10 min) is used as a normalizing factor. The generality of the unification technique is shown by analyzing rheological data for a wide variety of unmodified core asphalts under different temperature conditions. Based on a broad spectrum of covered data, it is concluded that the unified curves are applicable to all unmodified paving asphalts. The predictive ability of the unified curves is then checked and found to give reasonably reliable information. Thus, using a simple parameter like MVR which is determined quite accurately on a relatively inexpensive, easy-to-use flow measurement device (FMD), all fundamental rheological parameters of unmodified paving asphalts can be calculated from the unified curves without the actual data generation of viscoelastic properties through the dynamic shear rheometer.
Medical anthropology and international health planning.

Abstract International health planners have been slow to recognize that barriers slowing down the acceptance of modern medicine in traditional societies are just as much inherent in bureaucratic premises and operations as in the sociocultural forms of the recipient peoples. Beginning a generation ago anthropologists suggested an “adversary model” that posited a contest between modern and traditional medicine based largely on cultural dissonance, to explain resistances to change. Today it appears that quality, cost, and convenience of modern medicine rather than cultural incompatibility are the primary determinants of its acceptance. Medical role perceptions and the social costs of changes and reorganizations in health organizations are noted as problems in designing the most appropriate health services for developing countries. Possible roles for traditional healers in helping provide primary health care are discussed. Except for the use of indegenous midwives and perhaps mental illness specialists, it is argued, this approach will enjoy little success. In addition to doubts stemming from differing ideas of traditional and modern curers about etiologies and treatment, the proposal is based on an erroneous premise: that traditional healers will continue to be produced at the same rate as in the past. Contemporary evidence suggests their numbers will drop to a point where they will not constitute an adequate manpower reservoir, even should they be deemed accaptable on other grounds.
ORGANIZATION OF THE nif GENES OF THE NONHETEROCYSTOUS CYANOBACTERIUM TRICHODESMIUM SP. IMS101

An approximately 16-kb fragment of the Trichodesmium sp. IMS101 (a nonheterocystous filamentous cyanobacterium) "conventional"nif gene cluster was cloned and sequenced. The gene organization of the Trichodesmium and Anabaena variabilis vegetative (nif 2) nitrogenase gene clusters spanning the region from nif B to nif W are similar except for the absence of two open reading frames (ORF3 and ORF1) in Trichodesmium. The Trichodesmium nif EN genes encode a fused Nif EN polypeptide that does not appear to be processed into individual Nif E and Nif N polypeptides. Fused nif EN genes were previously found in the A. variabilis nif 2 genes, but we have found that fused nif EN genes are widespread in the nonheterocystous cyanobacteria. Although the gene organization of the nonheterocystous filamentous Trichodesmium nif gene cluster is very similar to that of the A. variabilis vegetative nif 2 gene cluster, phylogenetic analysis of nif sequences do not support close relatedness of Trichodesmium and A. variabilis vegetative (nif 2) nitrogenase genes.
Uncertainty in multi-media fate and transport models: A case study for TNT life cycle assessment

Life cycle assessment (LCA) is an evaluation method used by decision-makers to help assess the relative environmental impacts of various industrial processes. Despite that many LCA methods remain sensitive to uncertain input data, which can reduce the utility of their results, uncertainty arising from constituent LCA models remains poorly understood. Here, we begin to address this problem by evaluating the extent to which parameter-value uncertainty affects the SimpleBox 2.0 fate and transport model, which serves as a backbone for many LCA ecotoxicological impact categories. Two Monte Carlo type sampling methods were used to evaluate dispersion in steady-state concentration values for three chemicals involved in grenade production: toluene, 2,4-dinitrotoluene (2,4-DNT), and 2,4,6-trinitrotoluene (TNT). Parameters were first sampled stochastically one-at-a-time, then by randomly exploring a local patch of the parameter space. We confirmed that global temperatures contribute primarily to the overall variance of model results, which at most spanned approximately 8 decades in magnitude. These results are consistent with previous results obtained for the whole of the LCA method. LCA methods carry out calculations iteratively; a reduction in the error of a single component, such as the fate and transport model, may therefore improve its performance and utility as a decision-making aid.
American Indian and General Linguistics

ALEXANDER von Humboldt, the first of the great human geographers, in his preface to his brother Wilhelm's great three-volume posthumous work on Oceanic languages and on general linguistics (published by the Royal Academy of Sciences over the years from 1836 to 1839), comments on two aspects of Wilhelm's life work. Wilhelm's drive for scientific accomplishment led him to produce one of the first great works of comparative philology in which he not only describes the internal structure and traces the external cultural contacts of Javanese (2:1-203) but also places it in its larger Oceanic setting (2:207-424; 3) from the Philippines to Hawaii to Easter Island to Madagascar. His broadly humane interest in the relation between human language and human thought, however, led him to provide this great work with a four-hundred page introduction (l:i-cccxxx) in which he investigates the structure of a wide range of human languages (including many of the New World, such as Quechua, Yaruro, Nahuatl, and Delaware) and the possible bearing of that structure on the intellectual development of their speakers. Alexander suggests (1: ix-x) that a study of his brother's great work will not bear out the common prejudice that a man's worth is measured by the substantive materials with which he works and not by the manner in which he handles them. Rather its perusal will lead the reader to the conviction that greatness in the treatment of a subject does not spring from intellectual foundations alone, but from greatness of character, from a mind free of temporal restraints, and from unplumbed depths of feeling. Alexander himself was not a philologist, but he collaborated closely with his brother in gathering materials (A. von Humboldt 1826:l:xliii-xliv) on American Indian languages, particularly on those of New Spain. This activity, together with his wide-ranging concern with distributional characteristics of human attributes (including language), permit us to credit him with an important role in the stimulation of research in American Indian languages and in furthering general linguistic study in the Americas. Alexander's interests were broad, ranging from the contemporary distribution of human groups as they were manifest at the time of his extensive journeys through New Spain to the ancient origins and subsequent migrations of such groups. The attack on the problem of origins and migrations continues to be a major concern to historically minded linguists of today. Their approach is multi-faceted.
Racism, Citizenship and National Identity

Joanne Mariner addresses the concern of why the relative tolerance for racial and ethnic discrimination in citizenship policy? She suggests the question is particularly timely now, as increased immigration flows magnify the impact of discriminatory citizenship rules, and raise the spectre of long-term migrant populations being excluded from full membership in their countries of residence.
Convergent regular splittings for nonnegative matrices

MP matrices are those real matrices which possess a nonnegative, nonsingular l-inverse. This paper characterizes the nonnegative MP matrices and hence, determines when a nonnegative matrix A has a convergent regular splitting M—Q which induces the linear stationary iterative scheme x k+1=M −1 Qxk +M −1 b to solve Ax=b.
Crime Victimization: Assessing Differences Between Violent and Nonviolent Experiences

Experiencing a criminal victimization is among one of the most stressful human experiences. A cross-sectional study of victims of violent crime and victims of nonviolent crime suggests that there are statistically significant differences in experiences in the initial aftermath of the crime event and a few common effects. This article describes the common effects that are associated with criminal victimization in the context of intense distress and discusses the theoretical implications of well-being in the coping process. One hundred seventy-five victims of violent or nonviolent crime were interviewed. Implications for social work practice and theory and future research are delineated.
Reaction times to neon, LED, and fast incandescent brake lamps

Standard incandescent brake lamps have a relatively slow rise time. It takes approximately a quarter of a second for them to reach 90% of asymptotic light output, causing potential delays in responses by following drivers. The present study evaluated reaction times to brake signals from standard incandescent brake lamps and from three alternative brake lamps with substantially faster rise times: neon, LED, and fast incandescent. The study, performed in a laboratory, simulated a daytime driving condition. The subject's task was to respond as quickly as possible to the onset of either of two brake lamps in the visual periphery, while engaged in a central tracking task. Brake signals were presented at two levels of luminous intensity. The results showed that reaction times to the alternative brake lamps were faster than to the standard incandescent lamp, with the advantage averaging 166 ms for the LED and neon lamps, and 135 ms for the fast incandescent lamp. A reduction of the signals' luminous intensity from 42 cd to 5 cd increased the reaction time by 84 ms.
Document fraud deterrent strategies: four case studies

This paper discusses the approaches taken to deter fraud committed against four documents: the machine-readable passport; the machine-readable visa; the Consular Report of Birth Abroad; and the Border Crossing Card. General approaches are discussed first, with an emphasis on the reasons for the document, the conditions of its use and the information systems required for it to function. A cost model of counterfeit deterrence is introduced. Specific approaches to each of the four documents are then discussed, in light of the issuance circumstances and criteria, the intent of the issuing authority, the applicable international standards and the level of protection and fraud resistance appropriate for the document.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Folate-conjugated amphiphilic hyperbranched block copolymers based on Boltorn H40, poly(L-lactide) and poly(ethylene glycol) for tumor-targeted drug delivery.

Abstract Folate-conjugated amphiphilic hyperbranched block copolymer (H40–PLA- b -MPEG/PEG–FA) with a dendritic Boltorn ® H40 core, a hydrophobic poly( l -lactide) (PLA) inner shell and a hydrophilic methoxy poly(ethylene glycol) (MPEG) and folate-conjugated poly(ethylene glycol) (PEG–FA) outer shell was synthesized as a carrier for tumor-targeted drug delivery. The block copolymer was characterized using 1 H NMR and gel permeation chromatography (GPC) analysis. Due to its core–shell structure, this block polymer forms unimolecular micelles in aqueous solutions. The micellar properties of H40–PLA- b -MPEG/PEG–FA block copolymer were extensively studied by dynamic light scattering (DLS), fluorescence spectroscopy, and transmission electron microscopy (TEM). An anticancer drug, doxorubicin in the free base form (DOX) was encapsulated into H40–PLA- b -MPEG/PEG–FA micelles. The DOX-loaded micelles provided an initial burst release (up to 4 h) followed by a sustained release of the entrapped DOX over a period of about 40 h. Cellular uptake of the DOX-loaded H40–PLA- b -MPEG/PEG–FA micelles was found to be higher than that of the DOX-loaded H40–PLA- b -MPEG micelles because of the folate-receptor-mediated endocytosis, thereby providing higher cytotoxicity against the 4T1 mouse mammary carcinoma cell line. In vitro degradation studies revealed that the H40–PLA- b -MPEG/PEG–FA block copolymer hydrolytically degraded into polymer fragments within six weeks. These results indicated that the micelles prepared from the H40–PLA- b -MPEG/PEG–FA block copolymer have great potential as tumor-targeted drug delivery nanocarriers.
Electron- and photon-stimulated desorption: Benefits and pitfalls

Abstract Electron beam irradiation of solids often results in damage-producing events along with information-producing events. In the present paper we explore mechanisms of beam damage in solids, as well as examples of the benefits of electron- (and photon-) stimulated processes to study molecules at surfaces. Information about the geometrical structure of adsorbed species can be obtained from measurements of the angular distribution of ions released by electron- or photon-stimulated desorption. The directions of ion emission are directly related to the orientations of the surface bonds which are ruptured by the excitation. The method of Electron-Stimulated Desorption Ion Angular Distributions (ESDIAD) has proven particularly useful in characterizing local molecular structure at surfaces in the absence of long-range order; recent measurements of bonding configurations stabilized by impurities or by lateral interactions are discussed. Photon-stimulated desorption (PSD) studies using synchrotron radiation are providing new insights into fundamental electronic excitation processes at surfaces. Mechanisms for the excitation and desorption of ions are examined (valence, shallow core level and deep core level excitations), and examples include ion desorption from adsorbed monolayers, as well as ion formation and desorption processes in condensed molecular films.
Inhibition of very long chain acyl-CoA dehydrogenase during cardiac ischemia

The heart utilizes primarily fatty acids for energy production. During ischemia, however, diminished oxygen supply necessitates a switch from β-oxidation of fatty acids to glucose utilization and glycolysis. Molecular mechanisms responsible for these alterations in metabolism are not fully understood. Mitochondrial acyl-CoA dehydrogenase catalyzes the first committed step in the β-oxidation of fatty acids. In the current study, an in vivo rat model of myocardial ischemia was utilized to determine whether specific acyl-CoA dehydrogenases exhibit ischemia-induced alterations in activity, identify mechanisms responsible for changes in enzyme function, and assess the effects on mitochondrial respiration. Very long chain acyl-CoA dehydrogenase (VLCAD) activity declined 34% during 30 min of ischemia. Loss in activity appeared specific to VLCAD as medium chain acyl-CoA dehydrogenase activity remained constant. Loss in VLCAD activity during ischemia was not due to loss in protein content. In addition, activity was restored in the presence of the detergent Triton X-100, suggesting that changes in the interaction between the protein and inner mitochondrial membrane are responsible for ischemia-induced loss in activity. Palmitoyl-carnitine supported ADP-dependent state 3 respiration declined as a result of ischemia. When octanoyl-carnitine was utilized state 3 respiration remained unchanged. State 4 respiration increased during ischemia, an increase that appears specific to fatty acid utilization. Thus, VLCAD represents a likely site for the modulation of substrate utilization during myocardial ischemia. However, the dramatic increase in mitochondrial state 4 respiration would be predicted to accentuate the imbalance between energy production and utilization.
Glucocorticoid stimulation of choline-phosphate cytidylyltransferase activity in fetal rat lung: receptor-response relationships.

Abstract A number of previous studies using in vivo and cultured fetal lung models have shown that the activity of choline-phosphate cytidylyltransferase, the enzyme which catalyzes a rate-limiting reaction in de novo phosphatidylcholine synthesis, is increased by glucocorticoids and other hormones which accelerate fetal lung maturation. To examine the mechanism of this glucocorticoid action further, we examined the effect of dexamethasone on cytidylyltransferase activity in cultured fetal rat lung explants and related it to specific dexamethasone binding. Dexamethasone stimulated cytidylyltransferase activity in the homogenate, microsomal and 105 000 × g supernatant fractions. The hormone did not alter the subcellular distribution of the enzyme, however; the bulk of the activity was in the supernatant fraction in both the control and dexamethasone-treated cultures. The dose-response curves for stimulation of cytidylyltransferase activity in the supernatant fraction and specific nuclear binding of dexamethasone were similar and both plateaued at approx. 20 nM. The EC50 for cytidylyltransferase stimulation was 6.6 nM and the Kd for dexamethasone binding was 6.8 nM. The relative potencies of various steroids for stimulating choline-phosphate cytidylyltransferase and for specific nuclear glucocorticoid binding were the same: dexamethasone > cortisol = corticosterone = dihydrocorticosterone > progesterone. The stimulation by dexamethasone of cytidylyltransferase activity and of choline incorporation into phosphatidylcholine were both abolished by actinomycin D. These data show that the stimulatory effect of dexamethasone on fetal rat lung choline-phosphate cytidylyltransferase activity is largely on the enzyme in the supernatant fraction and does not involve enzyme translocation to the microsomes as has been reported for cytidylyltransferase activation in some other systems. This effect of dexamethasone is a receptor-mediated process dependent on RNA and protein synthesis.
Recruitment of host progenitor cells in rat liver transplants

Despite major histocompatibility complex incompatibility, liver transplants from Lewis rats to dark agouti (DA) rats survive indefinitely without immunosuppression, and the studies we report sought the mechanism(s) responsible for this. At 1 year, most of the liver reacted positively to host anti-DA antibody. When small (50%) grafts were transplanted, recruitment was more rapid because most of the organ assumed the host phenotype at 3 months. After transplantation, the Y chromosome was detected in the hepatocytes of XX to XY grafts by both in situ hybridization and polymerase chain reaction. Further, livers from transgenic Lewis rats carrying strong green fluorescent protein (GFP) markers lost the marker with time after transplantation to DA, GFP-negative hosts. Few liver cells contained the Y chromosome in syngeneic XX to XY liver grafts or when the hosts of Lewis XX to DA XY allografts were treated with cyclosporine A at 10 mg/kg/day. This dosage also impeded enlargement of the liver at 10 days. Using GFP-positive XX Lewis donors transplanted to GFP-negative XY DA hosts, we found little Y DNA in GFP-positive cells at 10 days. Host-derived OV-6-positive and c-kit-positive, albumin-positive cells were present at 3-10 days, but cells with the CD34 marker were less common and some clearly still had the donor phenotype at 10 days. Cells positive for chemokine cysteine-X-cysteine receptor-4 increased with time and were abundant 1 month after transplantation. We conclude: (1) extrahepatic cells can differentiate into liver tissues; (2) regenerative stimuli accelerate stem cell recruitment; (3) both regeneration and recruitment are impeded by cyclosporine A immunosuppression, and (4) donor GFP-positive cells contained little host Y chromosome after transplantation, suggesting that cell fusion was uncommon and, therefore, unlikely to be the mechanism leading to the changes in genotype and phenotype we observed.
Analysis of the RNA-Editing Reaction of ADAR2 with Structural and Fluorescent Analogues of the GluR-B R/G Editing Site†

ADARs are adenosine deaminases responsible for RNA editing reactions that occur in eukaryotic pre-mRNAs, including the pre-mRNAs of glutamate and serotonin receptors. Here we describe the generation and analysis of synthetic ADAR2 substrates that differ in structure around an RNA editing site. We find that five base pairs of duplex secondary structure 5' to the editing site increase the single turnover rate constant for deamination 17-39-fold when compared to substrates lacking this structure. ADAR2 deaminates an adenosine in the sequence context of a natural editing site >90-fold more rapidly and to a higher yield than an adjacent adenosine in the same RNA structure. This reactivity is minimally dependent on the base pairing partner of the edited nucleotide; adenosine at the editing site in the naturally occurring A.C mismatch is deaminated to approximately the same extent and only 4 times faster than adenosine in an A.U base pair at this site. A steady-state rate analysis at a saturating concentration of the most rapidly processed substrate indicates that product formation is linear with time through at least three turnovers with a slope of 13 +/- 1.5 nM.min(-1) at 30 nM ADAR2 for a k(ss) = 0.43 +/- 0.05 min(-1). In addition, ADAR2 induces a 3.3-fold enhancement in fluorescence intensity and a 14 nm blue shift in the emission maximum of a duplex substrate with 2-aminopurine located at the editing site, consistent with a mechanism whereby ADAR2 flips the reactive nucleotide out of the double helix prior to deamination.
Estimating Neighbourhood-Level Socio-Economic Effect on Preterm Births Using a Multilevel Approach: A Case Study in Georgia, USA

This study investigates the contextual effect of neighbourhood socio-economic status (SES) on the risk of preterm birth (PTB) using multilevel models. Birth data retrieved from 2000 Georgia Vital Records were geocoded and joined to their respective census tracts. The census tract level Index of Deprivation (IoD) was calculated using nine 2000 Census variables based on a previously proposed ‘standard’ index. Two-level random intercept regression models were developed using 117,329 live and singleton births at the individual level and 1618 census tracts at the neighbourhood level. After adjustment for individual-level factors, IoD generated an odds ratio of 1.006 (95% CI 1.00–1.01), showing a modest but significant effect on PTB. Intra-class correlation (ICC) was 0.83% after adjusting for individual-level factors and the census tract level IoD. A wide IOR-80% interval (0.74–1.36) suggests large unexplained residual in between census tract variation remained. The median odds ratio (MOR) value of 1.17 reveale...
Exciton-Dissociation and Charge-Recombination Processes in Pentacene/C60 Solar Cells: Theoretical Insight into the Impact of Interface Geometry

The exciton-dissociation and charge-recombination processes in organic solar cells based on pentacene/C60 heterojunctions are investigated by means of quantum-mechanical calculations. The electronic couplings and the rates of exciton dissociation and charge recombination have been evaluated for several geometrical configurations of the pentacene/C60 complex, which are relevant to bilayer and bulk heterojunctions. The results suggest that, irrespective of the actual pentacene−fullerene orientation, both pentacene-based and C60-based excitons are able to dissociate efficiently. Also, in the case of parallel configurations of the molecules at the pentacene/C60 interface, the decay of the lowest charge-transfer state to the ground state is calculated to be very fast; as a result, it can compete with the dissociation process into mobile charge carriers. Since parallel configurations are expected to be found more frequently in bulk heterojunctions than in bilayer heterojunctions, the performance of pentacene/C6...