cssi/SciSciGPT-SciSciNet huggingface dataset:
Pharmacokinetics of subcutaneous recombinant human granulocyte colony-stimulating factor in children.

Fifteen children (age 1.2 to 9.4 years) with advanced neuroblastoma were treated with myelosuppressive chemotherapy (cyclophosphamide, cisplatin, doxorubicin) followed by 5 (n = 5), 10 (n = 5), or 15 (n = 5) micrograms/kg recombinant granulocyte colony-stimulating factor (rG- CSF) subcutaneously (SC) once daily for 10 days, starting the day after chemotherapy. Serial serum samples obtained on days 1 and 10 were analyzed for G-CSF activity by a specific proliferation assay using NFS- 60 cells. G-CSF serum concentration-time data were best described by a one-compartment model, with zero-order absorption and first-order elimination. After SC injection, absorption was prolonged, with peak concentrations of G-CSF (3 to 117 ng/mL) being reached after 4 to 12 hours. The relatively slow absorption, with a mean elimination half- life of 5.8 hours on day 1 and 4.5 hours on day 10, provided measurable G-CSF concentrations for the entire 24-hour dosing interval in all patients at each dosage level. The median apparent clearance of G-CSF on day 10 was significantly higher than on day 1 (0.57 v 0.31 mL/min/kg, P = .02), and was positively correlated with the absolute neutrophil count (ANC) (r2 = .33, P = .003). Systemic exposure to G-CSF was dose-related, but interpatient pharmacokinetic variability yielded overlap in area under the concentration-time curve (AUC) at all three dosage levels. Stepwise regression analysis showed that G-CSF AUC could be predicted by a model that includes rG-CSF dosage and ANC on the day of administration (r2 = .82, P = .0001).
Evaluation of highly accelerated real-time cardiac cine MRI in tachycardia

Electrocardiogram (ECG)-gated breath-hold cine MRI is considered to be the gold standard test for the assessment of cardiac function. However, it may fail in patients with arrhythmia, impaired breath-hold capacity and poor ECG gating. Although ungated real-time cine MRI may mitigate these problems, commercially available real-time cine MRI pulse sequences using parallel imaging typically yield relatively poor spatiotemporal resolution because of their low image acquisition efficiency. As an extension of our previous work, the purpose of this study was to evaluate the diagnostic quality and accuracy of eight-fold-accelerated real-time cine MRI with compressed sensing (CS) for the quantification of cardiac function in tachycardia, where it is challenging for real-time cine MRI to provide sufficient spatiotemporal resolution. We evaluated the performances of eight-fold-accelerated cine MRI with CS, three-fold-accelerated real-time cine MRI with temporal generalized autocalibrating partially parallel acquisitions (TGRAPPA) and ECG-gated breath-hold cine MRI in 21 large animals with tachycardia (mean heart rate, 104 beats per minute) at 3T. For each cine MRI method, two expert readers evaluated the diagnostic quality in four categories (image quality, temporal fidelity of wall motion, artifacts and apparent noise) using a Likert scale (1–5, worst to best). One reader evaluated the left ventricular functional parameters. The diagnostic quality scores were significantly different between the three cine pulse sequences, except for the artifact level between CS and TGRAPPA real-time cine MRI. Both ECG-gated breath-hold cine MRI and eight-fold accelerated real-time cine MRI yielded all four scores of ≥ 3.0 (acceptable), whereas three-fold-accelerated real-time cine MRI yielded all scores below 3.0, except for artifact (3.0). The left ventricular ejection fraction (LVEF) measurements agreed better between ECG-gated cine MRI and eight-fold-accelerated real-time cine MRI (mean difference, –1.6%) than between ECG-gated cine MRI and three-fold-accelerated real-time cine MRI (mean difference, –5.7%). Eight-fold-accelerated real-time cine MRI with CS yields acceptable diagnostic quality and relatively accurate LVEF measurements in the challenging setting of tachycardia. Copyright © 2013 John Wiley & Sons, Ltd.
A simple technique to determine the extent of abdominal aortic aneurysms on B‐mode sonography

A simple technique is presented to evaluate extension of abdominal aortic aneurysms above the level of the renal arteries at sonography. Knowledge of such extension is important because these cases may require a thoroacoabdominal surgical approach. Iliac extension of abdominal aortic aneurysms also may be evaluated by sonography.
Does endotoxin contribute to aseptic loosening of orthopedic implants

Aseptic loosening of orthopedic implants caused by wear particles is a major clinical problem. This review examines the hypothesis that bacterial endotoxin contributes to aseptic loosening. Clinical findings support this hypothesis: bacterial biofilms exist on many implants from patients with aseptic loosening and antibiotics in bone cement reduce the rate of aseptic loosening. Three approaches were used to demonstrate that adherent endotoxin increases bioactivity of titanium particles. These experiments measured cytokine production and osteoclast differentiation in vitro and murine calvarial osteolysis in vivo. First, removal of >99.9% of the adherent endotoxin from titanium particles significantly ablates their biological activity. Second, adding lipopolysaccharide back to these "endotoxin-free" particles restores their biological activity. Third, cells or mice that are genetically hyporesponsive to endotoxin are significantly less responsive to titanium particles than are wild-type controls. Other investigators have confirmed and extended these results to include virtually all orthopedically relevant types of particles, including authentic titanium alloy particles retrieved from patients with loosening. Our recent studies suggest that adherent endotoxin on orthopedic implants may also inhibit initial osseointegration of the implants. Taken together, these studies suggest that bacterial endotoxin may have a significant role in induction of aseptic loosening.
Chronic ethanol inhibits CXC chemokine ligand 10 production in human A172 astroglia and astroglial-mediated leukocyte chemotaxis.

Abstract Astroglia are the most prevalent cell type in the human central nervous system (CNS) and perform important roles in normal tissue homeostasis, during pathological events and following trauma. Astroglial-derived chemokines have important neurotrophic effects and are important to CNS immunocompetence and response to injury, in part, due to their direct role in leukocyte and microglial cell recruitment. However, while ethanol is known to induce CNS pathologies and to be peripherally immunosuppressive, ethanol effects on chemokine expression in human astroglia are essentially unknown. We have demonstrated that chemotaxis of human U937 leukocytic cells, across a 0.5 μm pore polycarbonate transmembrane insert, is induced in response to culture media collected from 10 μg/ml lipopolysaccharide (LPS)+10 ng/ml interleukin (IL)-1β-stimulated A172 human astroglia cells. The involvement of the chemokine CXCL10 (also known as interferon-γ inducible protein or IP-10) in astroglial-induced chemotaxis of U937 cells has been indicated, as chemotaxis can be reduced by an anti-CXCL10 neutralizing antibody. Interestingly, chemotaxis of U937 cells, in response to astroglial-exposed media, is reduced when astroglia are chronically (9 days) exposed to 50 mM ethanol before stimulation with LPS+IL-1β. Furthermore, we observed that LPS+IL-1β-stimulated CXCL10 production is inhibited in human A172 astroglia exposed to chronic 50 mM ethanol. Thus, alterations in astroglial CXCL10 expression may disrupt CNS immunocompetence and play an important role in ethanol-induced CNS pathologies.
An Application of the Residue Calculus: The Distribution of the Sum of Nonhomogeneous Gamma Variates

The calculus of residues is one of the many beautiful tools that comes out of the field of complex variables. The calculus of residues is applied, together with the inversion formula for characteristic functions, to compute the non-gamma probability density function for the sum of gamma variates with different shape parameters. The distribution of the sum of gamma variates is needed in problems in statistical inference, as well as stochastic processes. This derivation seems more elegant than previous methods for deriving the density function of such a sum. Furthermore, the numerical computation is straightforward, especially in any symbolic computer language.
Race and Prevailing Wage Laws in the Construction Industry: Comment on Thieblot

Using the 1990 Census of Population, Thieblot (1999) argued that black employment and the strength of the prevailing wage laws are correlated and that repeal of these laws would lead to higher black employment in construction. Analysis of the 1970 Census of Population reveals that the relative abundance of black construction workers in the group of states that eventually would repeal their laws preceded those repeals and that this is mainly due to the characteristics of Southern labor markets. This and other research cast doubt on both the strength and the existence of such a correlation.
An iterative approach from the standpoint of the additive hypothesis to the dendrogram problem posed by molecular data sets.

Abstract The problem of constructing a dendrogram depicting phylogenetic relationships for a collection of contemporary species is considered. An approach was developed based on the additive hypothesis in which each “length” between two species can be described by the shortest sum of lengths for the individual links on the dendrogram topology which connect the two species. The additive hypothesis holds equally well if the dendro gram is replaced by its corresponding (rootless) network. Network topologies are defined set theoretically in terms of the initial, contemporary species, and a coefficient is defined for each point of any conceivable network. It is proved mathematically that each point of an additive network gives a coefficient value of zero, whereas each point not belonging to an additive network gives a coefficient value greater than zero. This suggests an iterative procedure in which “false” network points are replaced by “true” ones, or more generally in which “very false” network points are replaced by “nearly true” ones. The first procedure follows from the mathematical proof and the second is confirmed by simulation. Since most real data sets are not additive in the strict sense, a real data example was presented in which the iterative procedure produced a plausible network topology.
Nocturnal rhabdom cycling and retinal hemocyte functions in crayfish (Procambarus) compound eyes. II. Transmission electron microscopy and acid phosphatase localization

Cytoplasmic synthetic organelles (Golgi complexes, polysomes, and rough and smooth endoplasmic reticulum) are present in most photoreceptor cells of the crayfish retina in winter throughout the late-night 24:00 to 06:00 h period. These same retinular cells contain few or no lysosome-like bodies. There is no evidence for autophagic receptor membrane breakdown even during the degradative phase (24:00 to 02:00 h) of the late-night quadrant. The fine structure of rhabdom microvillus bases and their continuity with retinular cell somata and endoplasmic reticulum differ characteristically in each of the three successive turnover phases between 24:00 and 06:00 h. Typical stalked attachment of microvillus clusters to retinular cell bodies is resumed by 06:00 h. A minority of retinulas are severely abnormal. Their rhabdoms are shorter and closer to the basement membrane while their receptor cell nuclei have descended proximally. During the degradative phase, the retinular somata may lack synthetic organelles altogether while their rhabdoms are disorganized, detached from their parent cytoplasm, and occasionally invaded by hemocytes. In contrast, synthetic organelles are numerous in the cytoplasm during the late synthetic phase (03:00 to 04:00 h) when photoreceptor membranes are less disrupted and cytoplasmic bridges between rhabdoms and cell bodies are intact. Both moderate late-night degradation of the rhabdom and the less frequent catastrophic breakdown seem to be mediated by extracellular lysozymes provided in part by retinal hemocytes. Acid phosphatase localization at the beginning of the degradative phase (24:00 to 00:30 h) demonstrates that invasive granulocytes are a primary source of this enzyme. Another hemocyte function previously hypothesized is proven here by finding phagocytized fragments of rhabdom and other retinal elements in most of the retinal macrophages during late-night synthetic and resting phases.
Detecting the Progression of Eye Disease: CUSUM Charts for Assessing the Visual Field and Retinal Nerve Fiber Layer Thickness

Purpose The cumulative sum (CUSUM) is proposed and tested in a group of glaucoma patients and healthy subjects as a method for monitoring disease progression and for identifying clinically significant step changes in visual structure or function.
Modified Tresca's yield condition and associated flow rules for anisotropic materials and applications

Abstract A modified Tresca's yield condition with associated flow rules for anisotropic materials was suggested. By using this approach, it was shown that problems of which the principal axes of anisotropy coincide with the principal axes of stress, can be solved simply. Examples having known solutions for isotropic cases were solved. The results demonstrated that great error may be resulted by postulating the plastic flow of a strained body of anisotropic material on the basis of its behavior if it were isotropic.
Confidentiality guaranteed: a noninvasive procedure for collecting sensitive information

We present a scheme in which subjects select balls from each of two urns, reporting only the result from the urn appropriate to their response to a sensitive question. Subjects can thus be induced to respond to the sensitive question while preserving confidentiality. Design aspects are discussed.
The use of schematic knowledge about sources in source monitoring

Source monitoring refers to mental processes leading to attributions regarding the origin of information. We tested Johnson, Hashtroudi, and Lindsay's (1993) assumption that prior source-relevant knowledge is used in some source-monitoring tasks. In two experiments using different domains of schematic knowledge, two sources presented information that was expected for one source and somewhat unexpected for the other. In a later source-monitoring test, participants decided whether items had been presented by Source A, by Source B, or were new. The results of both experiments show that source identification is better for expected items than for somewhat unexpected items. Multinomial modeling analyses revealed that when participants do not remember the source of information, they guess that it was presented by the expected source. These results provide evidence for the claim that source monitoring can be based on prior knowledge and support a guessing hypothesis.
Rheological Model Studies in Clay

The process of deformation in clays is visualized as the combination of recoverable deformation resulting from bending and rotation of individual particles and irrecoverable deformation due to relative movement between adjacent particles at their points of contact. The relative movement between particles is treated as a rate process in which interparticle bonds are continually broken and reformed as the deformation proceeds. Accordingly, the rate of deformation is governed by the activation energy associated with the rupture of interparticle bonds. Thus, in terms of a rheological model, the fundamental element consists of a spring, representing the recoverable deformation, in series with a rate process dashpot representing the irrecoverable deformation. Owing to the heterogeneous nature of the fabric of clay soils, i.e. varying particle size, shape, orientation, surface characteristics, etc., a wide range of activation energies, elastic stiffness, and other material properties is anticipated. This is accounted for by assuming a Gaussian distribution for the model properties. Thus, the complete rheological model postulated in this study consists of a combination of spring and dashpot elements covering the complete spectrum of model properties. The response of the rheological model is analyzed for creep and constant strain-rate loading. The analysis is accomplished numerically using a digital computer since no closed form solution exists for the non-linear systems of equations that result from this model. Experimental data for a number of triaxial tests on clays under various conditions of loading are presented for comparison with the model behavior.
Influenza A Virus PB1-F2 Protein Expression Is Regulated in a Strain-Specific Manner by Sequences Located Downstream of the PB1-F2 Initiation Codon

Translation of influenza A virus PB1-F2 occurs in a second open reading frame (ORF) of the PB1 gene segment. PB1-F2 has been implicated in regulation of polymerase activity, immunopathology, susceptibility to secondary bacterial infection, and induction of apoptosis. Experimental evidence of PB1-F2 molecular function during infection has been collected primarily from human and avian viral isolates. As the 2009 H1N1 (H1N1pdm09) strain highlighted, some swine-derived influenza viruses have the capacity to infect human hosts and emerge as a pandemic. Understanding the impact that virulence factors from swine isolates have on both human and swine health could aid in early identification of viruses with pandemic potential. Studies examining PB1-F2 from swine isolates have focused primarily on H1N1pdm09, which does not encode PB1-F2 but was engineered to carry a full-length PB1-F2 ORF to assess the impact on viral replication and pathogenicity. However, experimental evidence of PB1-F2 protein expression from swine lineage viruses has not been demonstrated. Here, we reveal that during infection, PB1-F2 expression levels are substantially different in swine and human influenza viruses. We provide evidence that PB1-F2 expression is regulated at the translational level, with very low levels of PB1-F2 expression from swine lineage viruses relative to a human isolate PB1-F2. Translational regulation of PB1-F2 expression was partially mapped to two independent regions within the PB1 mRNA, located downstream of the PB1-F2 start site. Our data suggest that carrying a full-length PB1-F2 ORF may not be predictive of PB1-F2 expression in infected cells for all influenza A viruses.
Polarization Test for the Multinomial Distribution

Abstract A multinomial distribution with k cells is said to be polarized if the total probability mass of the distribution is essentially concentrated into a fewer number of cells. In this article a criterion is developed for measuring polarization, and a statistical test is given for testing the hypothesis that a multinomial distribution has a given measure of polarization against the alternative hypothesis that the measure of polarization is larger. The given test is called a polarization test and is shown to be unbiased.
Eigenproblem solution by a combined Sturm sequence and inverse iteration technique

Description of an efficient and numerically stable algorithm, along with a complete listing of the associated computer program, developed for the accurate computation of specified roots and associated vectors of the eigenvalue problem Aq = lambda Bq with band symmetric A and B, B being also positive-definite. The desired roots are first isolated by the Sturm sequence procedure; then a special variant of the inverse iteration technique is applied for the individual determination of each root along with its vector. The algorithm fully exploits the banded form of relevant matrices, and the associated program written in FORTRAN V for the JPL UNIVAC 1108 computer proves to be most significantly economical in comparison to similar existing procedures. The program may be conveniently utilized for the efficient solution of practical engineering problems, involving free vibration and buckling analysis of structures. Results of such analyses are presented for representative structures.
Classroom makerspaces: Identifying the opportunities and challenges

This paper aims at introducing, identifying opportunities, presenting a vision and stakeholder driven challenges regarding the concept of classroom makerspaces. With the engineering design process at its core, the discussions are in the purview of K-college engineering classrooms. So as to provide a background and elucidate upon accomplishments to date, we first shed light on the history, elements and evolution of makerspaces. Then we present the motivation for this work rooted in educational theory and also put forth our vision for classroom makerspaces. The present day opportunities arising from the Next Generation Science Standards (NGSS) and expectations from science and engineering classrooms are then identified which serve as further motivation for this practice. The subsequent section on challenges is the result of a brainstorm by our team of engineering education researchers, who are well acquainted with the concept of classroom makerspaces and bring to the table a diverse set of experiences and knowhow from academia, education and engineering. This paper is aimed at aiding the academic community to understand these challenges and subsequently address them with future studies and practices, so as to be in a better position for inclusion of classroom makerspaces in educational institutions.
Oct-1 and CCAAT/Enhancer-binding Protein (C/EBP) Bind to Overlapping Elements within the Interleukin-8 Promoter THE ROLE OF Oct-1 AS A TRANSCRIPTIONAL REPRESSOR

Interleukin-8 (IL-8), a potent neutrophil chemoattractant, can be expressed at high levels by many different cell types after immune stimulation. In contrast, expression of IL-8 in these same cells is virtually absent in the unstimulated state, demonstrating the tight regulation of the IL-8 gene. Although much is known about how this gene is transcriptionally activated after immune stimulation, little is known about the regulation of the IL-8 promoter in the absence of immune activation. In this study we examine how the IL-8 promoter is transcriptionally regulated in the uninduced state and how these mechanisms are altered in response to immune stimulation by IL-1beta. Electrophoretic mobility shift assay and transfection studies show that the IL-8 promoter is transcriptionally regulated by both positive and negative elements. Although the nuclear factor-kappaB (NFkappaB) element regulates only inducible activity of the IL-8 promoter in response to stimulation with IL-1beta, the AP-1 and CCAAT/Enhancer-binding Protein (C/EBP) elements influence both basal and inducible activities. In contrast to these three positive regulatory elements, the binding of the ubiquitously expressed POU-homeodomain transcription factor, Oct-1, strongly represses transcriptional activity of the IL-8 promoter by binding independently to an element overlapping that of C/EBP.
THE CHABOT EMOTIONAL DIFFERENTIATION SCALE: A THEORETICALLY AND PSYCHOMETRICALLY SOUND INSTRUMENT FOR MEASURING BOWEN's INTRAPSYCHIC ASPECT OF DIFFERENTIATION

Bowen's theory (1978) of differentiation is the personality variable most critical to mature development and the attainment of psychological health. The study of psychological differentiation has been confounded by confusion regarding the constructs being studied and the measurement tools used to assess them. The purpose of this review is to introduce and demonstrate the utility and importance of the Chabot Emotional Differentiation Scale (CED; Chabot, 1993), a self-report instrument specifically designed to measure Bowen's intrapsychic aspect of differentiation, or an individual's ability to distinguish between emotional and intellectual functioning and utilize intellect in emotionally charged situations. Psychometric support for the CED, validation and cross-cultural studies to date, and implications for theory, research, and practice are presented.
CollaborationViz: Interactive Visual Exploration of Biomedical Research Collaboration Networks

Social network analysis (SNA) helps us understand patterns of interaction between social entities. A number of SNA studies have shed light on the characteristics of research collaboration networks (RCNs). Especially, in the Clinical Translational Science Award (CTSA) community, SNA provides us a set of effective tools to quantitatively assess research collaborations and the impact of CTSA. However, descriptive network statistics are difficult for non-experts to understand. In this article, we present our experiences of building meaningful network visualizations to facilitate a series of visual analysis tasks. The basis of our design is multidimensional, visual aggregation of network dynamics. The resulting visualizations can help uncover hidden structures in the networks, elicit new observations of the network dynamics, compare different investigators and investigator groups, determine critical factors to the network evolution, and help direct further analyses. We applied our visualization techniques to explore the biomedical RCNs at the University of Arkansas for Medical Sciences – a CTSA institution. And, we created CollaborationViz, an open-source visual analytical tool to help network researchers and administration apprehend the network dynamics of research collaborations through interactive visualization.
The nature of fullerene solution collisional dynamics. A 13C DNP and NMR study of the C60/C6D6/TEMPO system

Abstract The solution dynamical behavior of the novel fullerene, C 60 and free radical nitroxide, TEMPO in deuterated benzene (C 6 D 6 ) was examined utilizing a flow liquid—liquid intermolecular transfer (L 2 IT) 13 C dynamic nuclear polarization (DNP) technique. The 13 C DNP ultimate enhancement, 13 C NMR paramagnetic contact shift, and corresponding spin—lattice nuclear relaxation rates are consistent with a model for the C 6o /TEMPO nuclear—electron interaction which is dominated by a rotationally driven dipolar relaxation mechanism. A dipolar dominated enhancement was also observed for a solid—liquid intermolecular transfer (SLIT) 13 C DNP experiment employing the C 60 /C 6 D 6 system with polarization transfer from a silica phase immobilized nitroxide (SPIN) sample.
Integrin α4β1-dependent T Cell Migration Requires Both Phosphorylation and Dephosphorylation of the α4 Cytoplasmic Domain to Regulate the Reversible Binding of Paxillin

alpha 4 integrins mediate increased cell migration and decreased cell spreading because the alpha 4 cytoplasmic domain (tail) binds tightly to paxillin, a signaling adaptor protein. Paxillin binding to the alpha 4 tail is blocked by alpha 4 phosphorylation at Ser988. To establish the biological role of alpha 4 phosphorylation, we reconstituted alpha 4-deficient Jurkat T cells with phosphorylation-mimicking (alpha 4(S988D)) or non-phosphorylatable (alpha 4(S988A)) mutants. alpha 4(S988D) disrupted paxillin binding and also inhibited cell migration and promoted cell spreading. In contrast, the non-phosphorylatable alpha 4(S988A) resulted in a further reduction in cell spreading; however, this mutation led to an unexpected suppression of cell migration. The suppression of cell migration by alpha 4(S988A) was ascribable to enhanced alpha 4-paxillin association, because enforced association by an alpha 4-paxillin fusion led to a phenotype similar to that of the non-phosphorylatable alpha 4(S988A) mutant. These data establish that optimal alpha 4-mediated cell migration requires both phosphorylation and dephosphorylation of the alpha 4 cytoplasmic domain to regulate the reversible binding of paxillin.
The outcome of outpatient withdrawal from alcohol.

Summary A sample of 50 male military veterans, many of whom were heavily alcohol dependent, was studied in an outpatient withdrawal programme. Fifty-four per cent of the sample completed outpatient withdrawal, 22% were admitted to inpatient care and 24% dropped out from care. The ‘admitted’ group was distinguishable by a later age of onset of drinking and by higher dependence scores (SADQ) than the other two groups, and by higher daily cigarette consumption than the ‘completed’ group. Predictive factors for the group which dropped out from care could not be identified, though there was a trend for these patients to be younger, and none of them presented with a serious physical disorder. Four risk factors, including SADQ score, were selected which had some predictive value for admission to inpatient care.
Electro-optic effect in strained and lattice matched multiquantum well structures-role of excitonic resonances

Abstract The well known quantum confined Stark effect (QCSE) is currently being exploited to design optoelectronic devices based on electric field controlled absorption of photons. QCSE is also responsible for strong below exciton resonance changes in refractive index with applied field. These changes can be used for high speed couplers and switches in waveguides. This paper focuses on the use of strain to influence the excitonic resonances in In x Ga 1− x As/Al 0.2 Ga 0.8 As and In 0.53± x Ga 0.47∓ x As/InGaAsP multiple quantum wells. Experimental results are presented showing the effect of compressive and tensile strain on the refractive index changes. Theoretical results including the important HH-LH band mixing effects are presented for the electrooptic effect. In particular, the contribution of the excitonic part is discussed and is found to dominate the electro-optic effect near the bandedge.
1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine destroys dopamine neurons in explants of rat embryo mesencephalon

Explants of embryonic rat mesencephalon were grown in organotypic culture. Addition of 10 microM 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to the culture medium for 4 to 7 days resulted in loss of dopamine cell bodies and fiber outgrowths, as observed by fluorescence histochemistry. At the same time, the cultures showed decreased uptake of tritium-labeled dopamine. However, no signs of generalized toxicity were evident when the explant cultures were viewed by light and phase-contrast microscopy. These results show that MPTP exerts a relatively selective destructive action in dopamine neurons in vitro, similar to the action observed in humans and monkeys in vivo. Pargyline (10 microM), a monoamine oxidase inhibitor, protected the dopamine neurons in the explants. Organotypic cultures provide an experimental model for the study of the properties of MPTP in vitro.
DNA methylation in aging of mice.

Abstract Methylation of cytidine residues of DNA appears to be involved in the control of gene expression; therefore, hypomethylation of the DNA can be considered to be an active rather than a passive process. Previous studies of mammalian DNA methylation during aging have produced an assortment of results. In this study, we have examined the change in DNA base composition, including the change in 5-methyldeoxycytidine (m 5 dC) contents with age of mice. Livers pooled from 6 mice from each of six age groups between 6 and 31 months have been subjected to a sensitive analytical technique (HPLC). The DNA composition of different age groups is very consistent in most aspects. The ratio of ( dA + dT )/( dG + dC + m 5 dC ) as well as the sum of dC and m 5 dC remain constant throughout the animal's lifespan. However, a consistent gradual decline in m 5 dC content is noted as the age increases to 24 months. Thus, the 6-month-old animal pool exhibits the largest amount of m 5 dC (1.67 ± 0.2%), which is reduced consistently as the animal's age reaches 24 months. This decrease in m 5 dC is accompanied by an increase in dC. No further decrease in m 5 dC occurs after 24 months; in fact, the data could indicate an increase after that age. No dTs are apparently produced by deamination of m 5 dC.
Evaluating automatic parallelization in SUIF

This paper presents the results of an experiment to measure empirically the remaining opportunities for exploiting loop-level parallelism that are missed by the Stanford SUIF compiler, a state-of-the-art automatic parallelization system targeting shared-memory multiprocessor architectures. For the purposes of this experiment, we have developed a run-time parallelization test called the Extended Lazy Privatizing Doall (ELPD) test, which is able to simultaneously test multiple loops in a loop nest. The ELPD test identifies a specific type of parallelism where each iteration of the loop being tested accesses independent data, possibly by making some of the data private to each processor. For 29 programs in three benchmark suites, the ELPD test was executed at run time for each candidate loop left unparallelized by the SUIF compiler to identify which of these loops could safely execute in parallel for the given program input. The results of this experiment point to two main requirements for improving the effectiveness of parallelizing compiler technology: incorporating control flow tests into analysis and extracting low-cost run-time parallelization tests from analysis results.
Changing the substrate specificity of creatine kinase from creatine to glycocyamine: Evidence for a highly evolved active site

Eight variants of creatine kinase were created to switch the substrate specificity from creatine to glycocyamine using a rational design approach. Changes to creatine kinase involved altering several residues on the flexible loops that fold over the bound substrates including a chimeric replacement of the guanidino specificity loop from glycocyamine kinase into creatine kinase. A maximal 2,000-fold change in substrate specificity was obtained as measured by a ratio of enzymatic efficiency (k(cat)/K(M).K(d)) for creatine vs. glycocyamine. In all cases, a change in specificity was accompanied by a large drop in enzymatic efficiency. This data, combined with evidence from other studies, indicate that substrate specificity in the phosphagen kinase family is obtained by precise alignment of substrates in the active site to maximize k(cat)/K(M).K(d) as opposed to selective molecular recognition of one guanidino substrate over another. A model for the evolution of the dimeric forms of phosphagen kinases is proposed in which these enzymes radiated from a common ancestor that may have possessed a level of catalytic promiscuity. As mutational events occurred leading to greater degrees of substrate specificity, the dimeric phosphagen kinases became evolutionary separated such that the substrate specificity could not be interchanged by a small number of mutations.
Inversion of vegetation canopy reflectance models for estimating agronomic variables. II. Use of angle transforms and error analysis as illustrated by suits' model

The technique for inverting a vegetation canopy reflectance model described earlier (Goel and Strebel, 1983) is investigated further. The novel concept of an 'angle transform' is introduced. This concept allows the formation of functions of reflectances at different view zenith and azimuth angles, which are either sensitive or insensitive to a certain agronomic parameter. A proper combination of these functions can allow determination of all the important agronomic and spectral parameters from measured canopy reflectance data. The technique is demonstrated using Suits' (1972) model for homogeneous canopies. It is shown that leaf area index, leaf reflectance and transmittance, and average leaf angle all can be determined from the canopy reflectance at a set of selected view zenith and azimuth angles. A sensitivity analysis of the calculated values to the errors in the data is also carried out. Guidelines are formulated for the number and types of observations required to obtain the values of a particular canopy variable to within a given degree of accuracy for a given level of error in the measurement of canopy reflectance.
The enzymic oxidation of chloral hydrate to trichloroacetic acid

Abstract A DPN-dependent enzyme system which catalyses the oxidation of chloral hydrate to trichloroacetic acid has been isolated from liver and partially purified. No naturally occurring substrate for this enzyme has been found.
Ma Hezhi and the illustration of the book of Odes

This book is the first comprehensive study of an important monument of twelfth-century Chinese art, the imperially sponsored set of handscrolls transcribing and illustrating the poems in the ancient anthology known as the Book of Odes (Shijing), long canonized as a "Confucian classic." The project is reconstructed and analyzed as the centerpiece of Southern Song emperor Gaozong's efforts to bring about a dynastic revival and to persuade the Confucian official-elite of his own legitimacy to rule. The artist Ma Hezhi's compositions are shown to have been conceived in awareness of literary tradition and antiquarian currents in Song intellectual life. Vigorous connoisseurship is applied to solve the longstanding problem of separating "original" scrolls from "copies," and all extant scrolls are systematically catalogued in an appendix.
Angiographic Right and Left Ventricular Volume Determination in Normal Infants and Children

Right and left ventricular volumes were calculated from bi-plane cineangiograms using a previously descriped parallelepiped method. Seventeen children, 1 month-10 years of age, were studied. Mean right ventricular end-diastolic volume (EDV) was 64 ml/m2 for infants, 78 ml/m2 for children. Mean right ventricular end-systolic volume (ESV) was 30 ml/m2 for both age groups. Left ventricular EDV and ESV were smaller than their right ventricular correlates by 23% and 56%, respectively. Mean right ventricular ejection fraction was 0.52 for infants and 0.61 for children. Mean left ventricular ejection fraction was 0.79 and 0.74, respectively. Speculation Cineangiographic determination of right and left ventricular volumes from a single contrast injection provides an excellent method to simultaneously evaluate hemodynamic performance of the two ventricles. Analysis of frame to frame volume changes, coupled with exact measurements of ventricular pressure changes, may allow calculation of ventricular distensibility and contractility.
Photophysical Properties of Ag(I)-exchanged Zeolite A and the Photoassisted Degradation of Malathion

Three colored derivatives of Ag(I) doped A-type zeolite were prepared and analyzed spectroscopically at 77 K. These compounds have luminescence spectra containing several emission bands that become dominant at characteristic excitation wavelengths. The white AgA zeolite shows luminescence bands at 290, 350, 423, 500, and 550−650 nm, whereas the yellow- and red-colored zeolites show bands at 500, 545, and 625 nm. These bands are attributed to the presence of different silver clusters in zeolite A. Both the experimental and theoretical results suggest the formation of Ag−Ag bonded excimers and exciplexes in the zeolite host. The photodecomposition of malathion in dichloromethane at room temperature shows different decomposition products in the presence and absence of the AgA zeolite catalyst. In addition, the decomposition rates depend on the color of the AgA zeolite. The white, yellow, and red AgA zeolites produce photodecomposition rates with malathion that are 35, 18, and 20 times faster, respectively, t...
Theory of Color Vision

A theory of color vision is presented which attempts to account for the physics, physiology, and psychology of the color-vision process. Three types of photopigments are assumed to be distributed among five types of cones. It is suggested that color signals are of an opponent-colors variety from retina to lateral geniculate body, then coded in terms of the four psychologically unique colors from the lateral geniculate to the visual cortex. The theory is quantitative and provides an explanation of protanopia, deuteranopia, and tritanopia. A new color diagram is developed, based upon the simplest version of the theory. Suggestions are made concerning how this diagram might be modified to produce a more uniform color space, and the meaning of such modifications is discussed in terms of the theory.
Factors influencing quality of renal function in dog kidneys implanted after twenty-four hour preservation

Abstract Data from this study indicate that ischemia, rapid nephrectomy with harvesting of the kidney in the non-diuretic phase, and failure to hydrate either the donor or the recipient are deleterious to renal function and survival in the continuously perfused kidney reimplanted after twenty-four hours of preservation. The suggested mechanism of injury is vasoconstriction.
Progress and Prospects: genetic treatments for disorders of bones and joints

Gene therapies directed toward the treatment of arthritis and tissue repair continue to be the most active areas of research for bone and joint diseases. In the past 2 years, two trials in rheumatoid arthritis have been completed. a Phase I study reporting safety and a Phase I/II study that has yet to be published. An additional, small study has reported the first evidence of clinical efficacy. Two Phase I trials of gene therapy for osteoarthritis have also been initiated. There is much preclinical activity in developing AAV vectors for future trials in the gene therapy of arthritis. Research into tissue repair and regeneration remains at the preclinical stage, but a considerable volume of research attests to the promise of gene transfer in this arena, especially in the context of bone healing. For tissue repair, the major research questions are still which genes to use and how best to deliver them.
Questioning corporate codes of ethics

This paper argues that corporate Codes of Ethics lose their ability to further moral responsiveness because of the narrow instrumental purposes that inform their adoption and use. It draws on Jacques Derrida’s reading of Emmanuel Levinas to argue that, despite the fact that all philosophical language entails a certain violence, corporate Codes of Ethics could potentially play a more meaningful role in furthering ethical questioning within corporations. The paper argues that Derrida’s reading of Levinas’ notion of ‘the third’ could precipitate the emergence of a broader sense of ethical responsibility towards multiple others within corporations. Codes may also present the opportunity for corporations to engage in the reconsideration of their own purposes in the light of questions of justice towards multiple others. How these changes in the establishment and use of Codes may be accomplished is explored towards the end of the paper.
Synovial factors and chondrocyte-mediated breakdown of cartilage: inhibition by hydrocortisone.

Cartilage-synovium interactions were explored in a model culture system. Bovine nasal-cartilage discs were cocultured with minced rheumatoid synovium or synovium-conditioned media (SCM) in the presence or absence of hydrocortisone. Cartilage breakdown was assessed by the release of proteoglycan (PG) and hydroxyproline, and matrix biosynthesis by [35S]sulfate incorporation during pulse labeling. Chondrocyte-dependent breakdown in response to synovial factors (i.e., "catabolin" activity) was assessed by the difference in PG release between living and dead cartilages. Short-term contact with minced synovial membrane or exposure to its products released at a distance was sufficient to induce cartilage degradation in coculture; continued exposure was not required for breakdown to persist. Conditioned media from short-term synovial culture were similarly potent, and the induced breakdown was chondrocyte dependent. Matrix biosynthesis was inhibited in exposed cartilage but could be rapidly restored to normal on synovium removal despite the persistence of cartilage breakdown. Early hydrocortisone treatment suppressed the initiation of cartilage breakdown in cocultures and largely abolished the appearance of inductive factors in SCM. Later applications had little effect either in cocultures or in catabolin assays. We conclude that synovium-induced breakdown is an early event and that chondrocyte catabolic mechanisms once they have been activated are sufficient to maintain breakdown at a high level. Hydrocortisone, as well as limiting proteolysis, inhibits early tissue interactions at the level of synovial catabolin production or release.
Aging and the alteration of enzymes: A review

The present status of research on age-related alterations of enzymes is reviewed. Evidence which makes it clear that "altered" enzymes do, in fact, exist in old animals is presented. The alteration may result from either a sequence change or a post-synthetic modification. The "error hypothesis" would support the former mechanism; a proposal based upon increasing half-lives of proteins with age could explain the latter. Evidence supporting or contradicting these alternatives is discussed.
Can Trade Liberalization Stimulate Economic Growth in Africa

Abstract This paper examines changes in economic growth that are likely to result from changes in trade policies, exports, and investment in 12 sub-Saharan African (SSA) countries. Using a vector error correction model (VECM), our results indicate that trade policies, exports, and investment rate shocks have a significant impact on economic growth in 10 of the 12 SSA countries. This suggests that it is possible to stimulate economic growth in some African countries through an outward-looking strategy of export expansion. More significantly, the results further suggest the importance as well as the need for African countries to embark on trade liberalization policies in order to enhance economic growth in the current world economy.
Motion video analysis using planar parallax

Motion and structure analysis in video sequences can lead to efficient descriptions of objects and their motions. Interesting events in videos can be detected using such an analysis--for instance independent object motion when the camera itself is moving, figure-ground segregation based on the saliency of a structure compared to its surroundings. In this paper we present a method for 3D motion and structure analysis that uses a planar surface in the environment as a reference coordinate system to describe a video sequence. The motion in the video sequence is described as the motion of the reference plane, and the parallax motion of all the non-planar components of the scene. It is shown how this method simplifies the otherwise hard general 3D motion analysis problem. In addition, a natural coordinate system in the environment is used to describe the scene which can simplify motion based segmentation. This work is a part of an ongoing effort in our group towards video annotation and analysis for indexing and retrieval. Results from a demonstration system being developed are presented.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
New equivalent circuits for elementary piezoelectric transducers

New equivalent circuits, having several advantages over previous circuits, are presented for three types of piezoelectric transducer: the thickness-expander plate, the end-electroded bar and the side-electroded bar. Each of the circuits involves an electrical network of frequency-dependent components connected to the centre of an acoustic transmission line.
Surgical conditions of the knee joint

Abstract I have presented some of the important surgical conditions of the knee joint. The percentage of cures and satisfactory results following arthrodesis for tuberculosis is high. Arthroplasty for ankylosis is now well standardized and sufficiently good results can be obtained to warrant its use in properly selected cases. Synovectomy, in our experience, has not been as satisfactory as we would wish. We are employing it with more caution and less often than formerly. Removal of fractured, torn, loose or injured semilunar cartilages gives a high percentage of good results. Operations for dislocations of the patella may be undertaken with great confidence.