cssi/SciSciGPT-SciSciNet huggingface dataset:
Design and Fabrication of End Platens for Acquisition of Small-Strain Piezoelectric Measurements During Large-Strain Triaxial Extension and Triaxial Compression Testing

A triaxial testing device was integrated with piezoelectric transducers to measure small-strain (<10−3%) dynamic soil properties during large-strain (15 %) triaxial testing. To incorporate the technology into existing equipment, end platens were designed and fabricated to facilitate direct contact between the transducers and the soil specimen. The platens protected the sensitive electronics while providing a seal between the confining fluid and the pore fluid. Two types of transducers were incorporated into the apparatus, bender elements and bender disks, used to measure shear wave and compression wave velocities, respectively. The 3.81-cm (1.5-in.) diameter acrylic end platens were designed to house the transducers, a porous stone, and openings to facilitate pore fluid drainage and wiring for the transducers. The top platen included a vacuum attachment and piston mount that enabled triaxial compression and triaxial extension testing. Removable stainless steel inserts were designed and fabricated to house and secure the transducers. These stainless steel inserts were used to ground the apparatus and allowed for maintenance and, if necessary, replacement of individual transducers. To ensure that the transducers were not damaged when subjected to the pore fluid, the transducers were waterproofed. Accurate readings of shear wave and compression wave velocities were obtained via proper design, fabrication, calibration, and implementation of the integrated small-strain components. Accurate readings of axial deformation, shear stress, and confining stress were also obtained via proper design, fabrication, and implementation of the vacuum connection components. Calibration results, as obtained from tests on specimens of medium-dense, dry, Ottawa sand, are presented and discussed. The system time delay was determined to be 5.67 × 10−5 seconds for the bender elements and 3.50 × 10−5 seconds for the bender disks. Measured shear wave velocity values ranged between 178 and 251 m/s and the corresponding compression wave velocity values ranged between 291 and 451 m/s.
Evidence for Non-Statistical Structure in the Inelastic Scattering of Polarized Protons from 26Mg

The analyzing power Ay for inelastic scattering from 26Mg has been measured as a function of incident proton energy Ep in 50 keV steps from 5.5 to 9.5 MeV for a variety of scattering angles. Statistical analysis1) of these data reveals evidence for intermediate structure in the excitation functions of Ay, although previous analysis of cross-section data indicated no deviations from the statistical model2).
New directions in the delivery of drugs and other substances to the central nervous system.

Publisher Summary The development of techniques aimed at the successful delivery of drugs to the CNS has most recently focused directly on the problem of penetrating the blood–brain barrier (BBB). Three main approaches have been used in this chapter: modifying the barrier, modifying the agents, and circumventing the barrier. The best method for CNS delivery should be noninvasive and allow the drug to be localized to specific parts of the brain. It should be applicable for a broad range of compounds, and it should be appropriate for both long-term and short-term use. The chapter contains a partial summary of the technologies available and some of their advantages and disadvantages. In the next few decades, there may be an increased need for the effective delivery of therapeutic agents to the CNS. The research aims to meet these intensifying demands by improving the present technology, combining current drug delivery methods, or developing altogether new methods.
Internet-based reverse engineering

Applications of reverse engineering for speeding up a product realisation process have gained momentum in recent years. The Internet has found increasing applications in manufacturing. Internet-based reverse engineering takes advantage of these areas. This paper presents the methodology of Internet-based reverse engineering, and a case study illustrates its applications in integrating CAD and CAM.
Randomized parallel computation

The subject of this thesis is randomized parallel algorithms. The goal is to demonstrate the power of randomization in designing efficient parallel algorithms for various computational problems. The specific problems we are concerned with are: sorting, routing, and combinatorial optimization. A survey of existing randomized parallel algorithms for many important problems is given first. This is followed by a procedure for deriving randomized parallel algorithms for selection and sorting. Next we present optimal algorithms for sorting both general and integer keys. We also present algorithms that run in sub-logarithmic time. A very important problem in parallel computation is routing. We give an optimal algorithm for permutation routing on a square mesh. We also identify a class of mesh-like networks that have optimal diameter. Many heuristic algorithms have been proposed for solving presumably hard combinatorial problems (like the travelling salesman problem etc.). Simulated Annealing is one such heuristic that employs randomization. We modify this procedure for problems that have certain separation properties. We prove this modified procedure (called Nested Annealing) has a worst case performance better than that of Simulated Annealing. Nested Annealing is shown to be easily parallelizable.
Identification of betanin degradation products

Betanin in solution, upon heating, was found to hydrolyze to betalamic acid and cyclodopa-5-O-glycoside. This reaction was monitored by an analytical high performance liquid chromatography (HPLC) method. The products were isolated by preparative reversed-phase HPLC or column chromatography using anion-exchange resins. Derivatives of betalamic acid (anilide, semicarbazone, condensation with L-proline) and cyclodopa-5-O-glycoside (hexacetate) were prepared as evidence to support the identification of these decomposition compounds. Formation of decarboxylated betanin was proposed based on the identification of CO2, chromatographic properties and the light absorption characteristics of the decarboxylated product.
A 1 GHz CMOS RF Front-End IC with Wide Dynamic Range

A 1 GHz Low Noise Amplifier and Mixer combination has been integrated in a standard 1?m CMOS process. The circuit is matched to 50? at the input, and drives a 50? load. Overall conversion gain is 22 dB, noise figure is 3.5 dB, and the IIP3 of the combination is +12 dBm. The fully balanced circuit drains 8 mA from 3V.
Subcarrier and bit allocation strategies for OFDMA based wireless ad hoc networks

Orthogonal frequency division multiple access (OFDMA) is an emerging multiple access technology. We consider OFDMA in the context of fixed wireless ad hoc networks. We address the problem of assigning subcarriers and bits to point-to-point wireless links in the presence of cochannel interference and Rayleigh fading. The objective is to minimize the total transmitted power over the entire network while satisfying the data rate requirement of each link. We formulate this problem as a constrained optimization problem and present a heuristic algorithm. The simulation results show that our algorithm results in an efficient assignment of subcarriers and transmitter power levels in terms of the energy required for transmitting each bit of information.
[Me8Pt4ReS4]− and related PtMe2-containing clusters derived from tetrathiorhenate

Abstract The reactions of Pt2Me4(μ-SMe2)2 and [ReS4]− in MeCN solution have been investigated. The resulting polyalkylated clusters: Et4N[ReS4PtMe2] (Et4N[1]), Et4N[ReS4(PtMe2)2] (Et4N[2]), and Et4N[ReS4(PtMe2)4] (Et4N[4]), were characterized by 1H, 13C, 195Pt NMR spectroscopy and ESI mass spectrometry. The structure of Et4N[1] was confirmed by single crystal X-ray diffraction, which demonstrated the expected square planar and tetrahedral coordination spheres bridged by a pair of sulfur atoms.
Trial of labor following cesarean section: a two-year experience.

Abstract Elective repeat cesarean section is one of the major factors responsible for the increase in the total cesarean section rate observed since 1970. Beginning in January 1980, a voluntary program encouraging a trial of labor for patients with a documented previous low-transverse cesarean section and no apparent recurring indication was instituted. Two hundred seven patients were managed with an adequate trial of labor, and 84.5% were delivered vaginally over a 2-year period. There were no deaths associated with a trial of labor, and maternal and fetal morbidity was negligible. This voluntary program resulted in a 27.9% decrease in the repeat cesarean section rate over the 2 years reported. Patient and physician acceptance of such a program was evaluated by follow-up questionnaires. Current recommendations include a mandatory trial of labor in patients with only one previous low-transverse cesarean section and no current indication for cesarean delivery. A more liberal management policy regarding patients with two or more previous low-transverse cesarean sections also seems warranted.
High-Field Effects in Quantum-Confined Systems

The presence of high electric field, both in the gate- as well as in channel-direction, degrades the mobility, resulting in breakdown of familiar Ohm's law. Using the asymmetrical distribution function, we show that the velocity saturation arises due to realignment of electrons in and opposite to the applied electric field, Velocity is then limited by the thermal velocity for nondegenerate carriers and Fermi velocity for degenerate carriers, independent of the scattering-limited mobility. This ultimate velocity is further reduced by the carrier quantum remission process. Gate degradation of the mobility in the channel is shown as arising from the quantum-confinement effect, in direct contrast to the perceived gate-beating of electrons, The impact of these limitations on the performance of FETs is presented High ohmic mobility does not necessarily lead to high saturation velocity.
Comparing the variances of two dependent variables

Various methods have been derived that are designed to test the hypothesis that two dependent variables have a common variance. Extant results indicate that all of these methods perform poorly in simulations. The paper provides a new perspective on why the Morgan-Pitman test does not control the probability of a Type I error when the marginal distributions have heavy tails. This new perspective suggests an alternative method for testing the hypothesis of equal variances and simulations indicate that it continues to perform well in situations where the Morgan-Pitman test performs poorly.
Community cancer programs as strategic alliances: challenges and guidelines for action

This paper assesses the utility of strategic alliances as a way of expanding and improving the quality of cancer care provided in communities with limited access to major treatment centres. Alliances provide an organizational model for future community-based cancer programs by accommodating a growing need for interdependence among organizations and providers while permitting substantial independence and autonomy. Five managerial challenges to ensuring effective and efficient delivery of cancer services are identified: to secure mutually reinforcing exchanges between and within all levels of cancer care, to develop protocols and programs relevant to the unique characteristics of patients and providers, to provide treatment and cancer control services, to involve interdisciplinary teams of providers at all levels of care and to achieve quality assurance, improvement and evaluation. In addition, the paper includes a set of guidelines to facilitate the implementation of community cancer programs as strategic alliances: reaffirm the role of community oncologists, primary care physicians and nurses as partners in the program; define the structure and culture necessary for commitment rather than simply compliance; redefine the role of management; establish data-monitoring systems; modify reward systems; and set realistic time frames and expectations.
An integrated methodology for electronic assembly planning

The authors discuss an integrated planning, scheduling, and control methodology for electronic assembly. The activities of a placement workstation for electronic assembly are addressed. Placement sequence planning, vision analysis, inspection, and control issues of the developed methodology are discussed. The placement workstation is hierarchically controlled by the electronic manufacturing cell controller. The activities of the flexible placement workstation are performed by the planning/scheduling and control modules. The methodology described has been implemented on ROBOTWORLD. >
Expression of epigenetic modifiers is not significantly altered by exposure to secondhand smoke

Abstract Objectives Secondhand smoke (SHS) is a major risk factor for lung cancer in nonsmokers. DNA damage-derived mutagenicity is a well-established mechanism of SHS-carcinogenicity; however very little is known about the impact of SHS exposure on the epigenome. Materials and methods We have investigated whether exposure to SHS can modulate the expression of key epigenetic regulators responsible for the establishment and/or maintenance of DNA methylation and histone modification patterns in vivo . We have sub-chronically exposed mice to a mutagenic but non-tumorigenic dose of SHS, and subsequently determined the expression levels of major epigenetic modifiers in the lungs of SHS-exposed mice, immediately after termination of exposure and following 7-month recovery in clean air. Results and conclusion Quantification of the expression of genes encoding DNA methyltransferases ( Dnmt1 , Dnmt3a , Dnmt3b and Dnmt3l ), methyl binding domain proteins ( Mecp2 , Mbd2 and Mbd3 ) and histone deacetylases ( Hdac1 and Hdac2 ) by quantitative reverse-transcription polymerase chain reaction analysis showed modest but not statistically significant differences in the relative transcription of these key epigenetic regulators between SHS-exposed mice and age-matched controls. The non-significant changes in the expression of main epigenetic modifiers in SHS-exposed mice imply that SHS may predominantly induce genotoxic effects, particularly at non-tumorigenic doses, whereas epigenetic effects may only be secondary and manifest en route to tumor formation.
The QT Interval and Torsade de Pointes

The QT interval on the electrocardiogram is the time from the onset of ventricular depolarisation (the Q wave) to completion of repolarisation (the end of the T wave). It is influenced by heart rate, autonomic factors, electrolyte levels, gender and age. A prolonged QT interval indicates an increased risk of developing malignant ventricular tachyarrhythmias, particularly torsade de pointes. QT prolongation may be primary (inherited, familial, congenital, idiopathic) or caused by disease, drugs or toxins. Drugs that have been associated with the development of torsade de pointes include antiarrhythmic, antibacterial and psychotropic agents and antihistamines. Several of these drugs depress myocardial ion channels, particularly the rapidly activating delayed rectifier (repolarising) potassium current (IKr). Overdosage of drugs that affect the delayed rectifier (repolarising) potassium currents (Ik), or coadministration of these drugs with another medication that inhibits their metabolism (e.g. an antihistamine such as terfenadine with an antifungal agent such as ketoconazole, which inhibits the cytochrome P450 3A4 hepatic enzyme), can induce torsade de pointes. Torsade de pointes is a potentially life-threatening ventricular tachyarrhythmia and the risks of administering drugs that can induce this condition must be carefully considered.
Interaction of tobacco-specific toxicants with the neuronal α7 nicotinic acetylcholine receptor and its associated mitogenic signal transduction pathway: potential role in lung carcinogenesis and pediatric lung disorders

Pulmonary neuroendocrine cells function as hypoxia-sensitive chemoreceptors, and they release peptides and biogenic amines that are important mediators of pulmonary neonatal adaptation. Some of these products additionally act as autocrine growth factors. Increased numbers of pulmonary neuroendocrine cells have been observed in several smoking-associated pediatric lung disorders such as bronchopulmonary dysplasia, cystic fibrosis, sudden infant death syndrome, and asthma. Disturbed pulmonary neuroendocrine function has been implicated in the etiology of this disease complex. One of the most common smoking-associated lung cancer types, small cell lung carcinoma, expresses phenotypic and functional features of pulmonary neuroendocrine cells. We, as well as others, have shown that the release of the autocrine growth factors 5-hydroxytryptamine (5-HT, serotonin) and mammalian bombesisn/gastrin releasing peptide (MB/GRP) by cell lines derived from human small cell lung carcinoma or fetal hamster pulmonary neuroendocrine cells are regulated by a neuronal nicotinic acetylcholine receptor comprised of α7 subunits. In radio-receptor assays, nicotine and the nicotine-derived carcinogenic nitrosamines N′-nictrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) bound with high affinity to this receptor with affinitites NNK>nicotine>NNN. Binding of nicotine or NNK to the α7 receptor resulted in calcium influx and overexpression and activation of the serine–threonine protein kinase Raf-1. In turn, this event lead to overexpression and activation of the mitogen activated (MAP) kinases extracellular signal regulated kinase 1 (ERK1) and extracellular signal regulated kinase 2 (ERK2) and stimulation of DNA synthesis accompanied by an increase in cell numbers in fetal pulmonary neuroendocrine cells and small cell carcinoma cells. Exposure of fetal pulmonary neuroendocrine cells for 6 days to NNK caused a prominant up-regulation of Raf-1. Our findings suggest that chronic exposure to nicotine and NNK in pregnant women who smoke may up-regulate the α7 nicotinic receptor as well as components of its associated mitogenic signal transduction pathway, thus increasing the susceptibilities of the infants for the development of pediatric lung disorders. Similarly, up-regulation of one or several components of this nicotinic receptor pathway in smokers may be an important factor for the development of small cell lung carcinoma.
Groundwater quality and management in arid and semi-arid regions: Case study, Central Eastern Desert of Egypt

Abstract This study presents a model budget for groundwater in the Central Eastern Desert of Egypt. The stable isotopic composition and hydrochemistry of groundwater samples collected from different aquifers were determined to identify recharge sources and water quality. Stable isotopic values suggest that shallow alluvial and fracture zone aquifers are recharged from seasonal precipitation, while groundwater in deeper sedimentary sub-basins is paleowater that was recharged during periods of less arid regional climate. Hydrochemical analysis indicates elevated salinity in each aquifer type, which is attributed to leaching and dissolution of terrestrial salts and to mixing with marine water. Groundwater from sedimentary sub-basin aquifers can be treated and used for drinking and domestic purposes. Groundwater from shallow alluvial and fracture zone wells is suitable for animal husbandry and mineral ore dressing. A model water budget shows that approximately 4.8 × 10 9 m 3 of recoverable groundwater is stored in sedimentary sub-basin aquifers, or approximately 550 years of water at present utilization rates.
Current Recommendations for the Prophylaxis and Treatment of Rabies

Once onset of clinical rabies develops in an individual, death is inevitable. Thus, it is imperative that, for persons exposed or potentially exposed to rabies virus, prophylaxis must be instituted as soon as possible following the exposure. Local wound management is an essential part of postexposure rabies prophylaxis. Exposed persons should receive a recommended series of a tissue culture or cell culture origin vaccine. The number of doses and route of vaccination differ in various regions of the world and are discussed in the text. The administration of a rabies immune globulin is generally recommended in conjunction with the first dose of the rabies vaccine. Nerve tissue origin vaccines, although used extensively in some parts of the world, are not recommended if cell or tissue culture vaccines are available. Decision trees are presented in the text to aid in determining if rabies vaccine is necessary following a known or presumed exposure to the virus, along with a table outlining the various rabies vaccines available in the World. Rabies pre-exposure immunisation is recommended for those individuals at risk of exposure to the virus. Pre-exposure prophylaxis consists of 3 doses of an approved rabies vaccine administered either intramuscularly or intradermally on days 0, 7, and 21 or 28 with periodic booster doses or titre determination depending on the level of risk of potential exposure to the virus.
Some parameters affecting the activity of monoamine oxidase in purified bovine brain mitochondria.

— Some parameters affecting the activity of monoamine oxidase (MAO) in purified beef brain mitochondria were investigated, and diversities in enzyme properties were found as a function of substrate. The deamination of the biogenic amines: serotonin, dopamine, tyramine, tryptamine, phenylethylamine and two non-physiological amines, kynuramine and m-iodobenzylamine, was studied. Anions in high concentrations inhibited enzyme activity with kynuramine being the substrate most affected. Among the biogenic amines, the activity with the indolalkylamines showed greater sensitivity to mono-valent anions such as chloride than to polyvalent ions such as phosphate whereas the opposite was true with the phenylalkylamines. However, pyrophosphate ion had little or no effect on MAO activity, regardless of substrate. The inhibition of kynuramine and serotonin deamination was non-competitive but mixed competitive inhibition was found with tyramine and phenylethylamine. The activity of MAO was markedly affected by pH, and it had been previously reported that the substrates showed different pH optima in their oxidation. The effect of pH on activity has been attributed in part to changes in the ionization of the substrate and the hypothesis that the true substrate is the non-protonated amine. This was reflected in kinetic studies showing high substrate inhibition with increased pH. It was calculated that phenylethylamine would have the highest percentage of un-ionized amine at pH 8.2 and 9.1. At these pHs, there was more pronounced inhibition with high substrate concentrations of phenylethylamine than with the other substrates. In contrast, there was little inhibition with high substrate concentrations of tyramine which was the most ionizable of the substrates tested. When Km values obtained at pH 7.4, 8.2 and 9.1 were corrected for ionization of the substrate, the corrected Km was lowest at pH 7.4 for all substrates. Less than 50% of MAO activity was lost when beef brain mitochondria was heated at 50°C for 20 min. However, there was only a slight variation with substrate in the thermal inactivation experiments. It is concluded that the mitochondrial membrane environment surrounding the enzyme imposes certain restrictions on the enzymatic activity with respect to the different substrates which, in turn, are also affected by such parameters as pH and ions. The results are discussed in terms of the relationship of these factors to the question of enzyme multiplicity.
Effects of chronic administration of D-amphetamine on PGO wave activity in the cat.

Abstract The effects of depletion of serotonin by the chronic administration of amphetamine (twice daily, 7.5 mg/kg per injection on days 1–6; 15 mg/kg per injection on the remaining days, i.p.) for 10–14 days on ponto-geniculo-occipital (PGO) waves was examined in cats. While the regimen of pretreatment with amphetamine produced comparable decreases in the content of central serotonin (i.e. 40–70%) to those observed in other studies (i.e. with reserpine, p -chlorophenylalanine, methiothepin) of pontogeniculo-occipital wave activity, no ponto-geniculo-occipital waves of the rapid-eye-movement sleep type were observed during waking after chronic treatment with amphetamine. These results are discussed within the context of the “serotonin gating” hypothesis of the generation of pontogeniculo-occipital waves, an hypothesis which states that ponto-geniculo-occipital waves emerge into waking when a critical level of the depletion of serotonin is reached, thus opening the “gate” for ponto-geniculo-occipital waves to enter waking states. The present authors suggest that a gradual depletion of serotonin, such as occurs following the chronic administration of amphetamine, will not elicit ponto-geniculo-occipital waves into waking, whereas a rapid depletion of serotonin, such as occurs following treatment with reserpine, results in the emergence of ponto-geniculo-occipital waves into waking.
Cortical application of ribonuclease and amnesia for a visual discrimination

After reaching a 9/10 criterion in a black-white T maze or after overtraining on the same task a solution of RNAase or an appropriate control solution was applied to the posterior cortex of rats. Testing after application of the enzyme revealed amnesia for the task for an average of 5.0 days. Control groups returned to criterion performance in 2.2 days on the average. These data are unlike those obtained either with functional ablation or with trauma-induced amnesia.
Cost, staffing and quality impact of bedside electronic medical record (EMR) in nursing homes

Objective There is growing political pressure for nursing homes to implement the electronic medical record (EMR) but there is little evidence of its impact on resident care. The purpose of this study was to test the unique and combined contributions of EMR at the bedside and on-site clinical consultation by gerontological expert nurses on cost, staffing, and quality of care in nursing homes. Methods Eighteen nursing facilities in 3 states participated in a 4-group 24-month comparison: Group 1 implemented bedside EMR, used nurse consultation; Group 2 implemented bedside EMR only; Group 3 used nurse consultation only; Group 4 neither. Intervention sites (Groups 1 and 2) received substantial, partial financial support from CMS to implement EMR. Costs and staffing were measured from Medicaid cost reports, and staff retention from primary data collection; resident outcomes were measured by MDS-based quality indicators and quality measures. Results Total costs increased in both intervention groups that implemented technology; staffing and staff retention remained constant. Improvement trends were detected in resident outcomes of ADLs, range of motion, and high-risk pressure sores for both intervention groups but not in comparison groups. Discussion Implementation of bedside EMR is not cost neutral. There were increased total costs for all intervention facilities. These costs were not a result of increased direct care staffing or increased staff turnover. Conclusions Nursing home leaders and policy makers need to be aware of on-going hardware and software costs as well as costs of continual technical support for the EMR and constant staff orientation to use the system. EMR can contribute to the quality of nursing home care and can be enhanced by on-site consultation by nurses with graduate education in nursing and expertise in gerontology.
Enzyme-inorganic nanoporous materials: Stabilization of proteins intercalated in α-zirconium(IV) phosphate by a denaturant

Abstract Improving the stability of proteins and enzymes at solid–liquid interfaces is challenging and it has important implications in biocatalysis and biosensors. Here, we report that moderate concentrations of urea stabilize heme proteins, such as met-hemoglobin (Hb) or met-myoglobin (Mb) bound to α-zirconium phosphate (α-ZrP). The half-life of Hb intercalated in the galleries of α-ZrP, for example, increased from 127 h (no urea) to >235 h (2 M urea). The peroxidase-like activity of Hb intercalated in α-ZrP was also improved by the addition of urea, and the product yields increased from 44% (no urea) to 79% (2 M urea). These improvements are not limited to Hb, and similar results also observed with Mb. Urea also inhibited the dithionite reduction of the ferric form of the intercalated heme proteins to their corresponding ferrous forms but not the oxidation of the ferric form to the corresponding high valent iron-oxo species. These observations open new possibilities to control the properties of immobilized proteins.
Decomposable threshold models

Abstract Subjects who must decide whether an alternative is acceptable, whether a stimulus belongs to a specified category, or whether a stimulus is recognized as previously displayed, have often been modeled as attempting to determine whether a multidimensional stimulus exceeds a threshold. This paper examines and axiomatizes some general models for these discrete judgment tasks. The threshold models considered, viewed as models of preference, generalize the conjunctive and disjunctive rules, among other noncompensatory and compensatory decision rules. Viewed as models of categorization, the threshold models generalize independent cue models and the notion of linear separability of categories. For each threshold model considered, necessary and sufficient conditions are presented. The axiomatic analyses direct attention to the features of the models that can be subjected to empirical test. It turns out that the most general form considered is too general to be falsifiable. In each restricted case, the key feature of the model turns out to be a variant of a “context-independence” condition that is highly fasifiable.
Linear Low-Density Polyethylene Containing Precisely Placed Hexyl Branches

A structural investigation into model linear low-density polyethylene containing precise hexyl branches has been completed using metathesis chemistry. These models based on ethylene/1-octene (EO) copolymers are versions of industrially produced metallocene copolymers; however, they contain exact primary structures and constant methylene sequence lengths. Acyclic diene metathesis (ADMET) polymerization has been used to produce copolymers containing only hexyl branches on every 9th, 15th, or 21st carbon along the backbone of polyethylene. Thermal examination of these macromolecules has demonstrated the first narrow melting profile for EO copolymers with high 1-octene incorporation (111, 67, and 48 hexyl branches per 1000 carbons). Further, a new synthetic methodology has been developed to produce branched, pure diene functional monomers with the ability to produce any model LLDPE in good yields.
Axonal heparan sulfate proteoglycans regulate the distribution and efficiency of the repellent slit during midline axon guidance.

Abstract The presentation of secreted axon guidance factors plays a major role in shaping central nervous system (CNS) connectivity [1]. Recent work suggests that heparan sulfate (HS) regulates guidance factor activity; however, the in vivo axon guidance roles of its carrier proteins (heparan sulfate proteoglycans, or HSPGs) are largely unknown [2–4]. Here we demonstrate through genetic analysis in vivo that the HSPG Syndecan (Sdc) is critical for the fidelity of Slit repellent signaling at the midline of the Drosophila CNS, consistent with the localization of Sdc to CNS axons. sdc mutants exhibit consistent defects in midline axon guidance, plus potent and specific genetic interactions supporting a model in which HSPGs improve the efficiency of Slit localization and/or signaling. To test this hypothesis, we show that Slit distribution is altered in sdc mutants and that Slit and its receptor bind to Sdc. However, when we compare the function of the transmembrane Sdc to a different class of HSPG that localizes to CNS axons (Dallylike), we find functional redundancy, suggesting that these proteoglycans act as spatially specific carriers of common HS structures that enable growth cones to interact with and perceive Slit as it diffuses away from its source at the CNS midline.
Image Sampling And Interpolation

Various methods for image sampling and inter olation are considered. The use of Nyquist sampling is discussed; interpolation of sampled data by the use of pp-functions and B-splines is introduced; and the various methods are compared for the case of image samling. An elementary introduction to B-splines and their applications is given in a manner that lacks rigor but which should appeal to engineers.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Cyclic redundancy checks with factorable generators

Applications are proposed for cyclic redundancy checks (CRCs) that have factorable rather than primitive generator polynomials. Suitable encoding and decoding methods are developed. Factored-generator CRCs are then compared with tandem CRCs that have an inner code and outer code. When the factors of the generator are used as the generators of the inner and outer codes, the two kinds of CRCs have much in common, although their codewords are different. The differences are such that the factored-generator CRC offers an architectural advantage over the tandem CRC, in that the factored-generator CRC enables symmetric partial decoding, which is useful in mixed-transmission-media and point-to-multipoint systems.
Self-similar bending in a flow: The axisymmetric case

We study how sheets roll up into conical configurations when exposed to fluid flows using simulations and analysis. The simulations couple the bending of thin sheets to axisymmetric flows with vortex shedding. We find quasisteady flows with vortex ring wakes in which the radii of the rings scale with the radii of the cone bases. The cone angles scale with the dimensionless flow speed raised to the power −1/3. The drag coefficients for the cones scale with flow speed to the power −1. We find good agreement with the previously published experimental results. The scalings we have found result from a self-similar behavior of the flow at the outer edges of the cones, with length scales set by the radii of the vortex rings in the wakes.
The Sister-Chromatid Cohesion Protein ORD Is Required for Chiasma Maintenance in Drosophila Oocytes

Accurate chromosome partitioning during cell division requires that cohesion hold sister chromatids together until kinetochores correctly attach to spindle microtubules. In 1932, Darlington noted that sister-chromatid cohesion distal to the site of exchange also could play a vital role in maintaining the association of chiasmate homologs during meiosis. Cohesion linking a recombinant chromatid with a sister of each homologous pair would resist spindle forces that separate kinetochores of homologous chromosomes (see Figure 1). Although centromeric cohesion must be retained to ensure proper segregation during meiosis II, dissolution of arm cohesion would be required for anaphase I to occur. This hypothesis is supported by recent evidence in yeast and C. elegans that separase activity is essential for the segregation of recombinant homologs during meiosis I. We present evidence that Drosophila oocytes require sister-chromatid cohesion to maintain a physical attachment between recombinant chromosomes. Using FISH to monitor cohesion directly, we confirm that oocytes lacking ORD activity exhibit cohesion defects, consistent with previous genetic results. We also show that ord(null) oocytes that have undergone recombination are unable to arrest at metaphase I, indicating that chiasmata are unstable in the absence of cohesion. Our results support the model that arm cohesion provides a conserved mechanism that ensures physical attachment between recombinant homologs until anaphase I.
A new sphere packing in 20 dimensions

We construct a new nonlattice sphere packing in 20 dimensions which is denser than any 20-dimensional packing previously known. Properties of the new sphere packing are investigated.
Contrast medium causes the apparent increase in β-endorphin levels in human cerebrospinal fluid following brain stimulation

Abstract Levels of β-endorphin immunoreactivity in cerebrospinal fluid were measured in 12 chronic pain patients undergoing the surgical implantation of an electrode into the periventricular gray matter. Cerebrospinal fluid fractions were collected following placement of a cannula into the third ventricle, following injection of metrizamide contrast medium into the ventricles, following implantation of the electrode, and following electrical stimulation. A second set of samples was collected on a non-surgical day before and after stimulation. Levels of β-endorphin immunoreactivity increased significantly from baseline levels to post-electrode implantation in one group of patients, but no significant change was seen following the onset of stimulation. Immunoreactivity increased significantly following metrizamide injection in a second group and was still elevated, in comparison to baseline, following electrode placement, but no increase was seen following the onset of stimulation. Levels of immunoreactive β-endorphin did not increase in either group after stimulation on a post-surgical day, despite consistent reports of pain relief. Addition of metrizamide or a related contrast medium, iothalamate meglumine (Conray) to the β-endorphin radioimmunoassay revealed that both compounds interfered with antigen-antibody binding and also quenched the gamma radiation emitted by iodinated peptide ligands. Due to these combined effects, the contrast media alone produced results similar to those of the β-endorphin standard. Moreover, similar observations were made when contrast media were incorporated into radioimmunoassays for met-enkephalin, dynorphin and cholecystokinin octapeptide. These findings indicate that increased levels of β-endorphin in cerebrospinal fluid are not directly associated with patient report of pain relief following periventricular gray stimulation. This study also suggests that the previously reported association between periventricular gray stimulation and elevated levels of β-endorphin immunoreactivity in ventricular cerebrospinal fluid are artifactual due to the interaction of contrast media with the radioimmunoassay.
Magnetic Resonance Perfusion Imaging in Acute Ischemic Stroke Using Continuous Arterial Spin Labeling

Background and Purpose —Continuous arterial spin-labeled perfusion MRI (CASL-PI) uses electromagnetically labeled arterial blood water as a diffusible tracer to noninvasively measure cerebral blood flow (CBF). We hypothesized that CASL-PI could detect perfusion deficits and perfusion/diffusion mismatches and predict outcome in acute ischemic stroke. Methods —We studied 15 patients with acute ischemic stroke within 24 hours of symptom onset. With the use of a 6-minute imaging protocol, CASL-PI was measured at 1.5 T in 8-mm contiguous supratentorial slices with a 3.75-mm in-plane resolution. Diffusion-weighted images were also obtained. Visual inspection for perfusion deficits, perfusion/diffusion mismatches, and effects of delayed arterial transit was performed. CBF in predetermined vascular territories was quantified by transformation into Talairach space. Regional CBF values were correlated with National Institutes of Health Stroke Scale (NIHSS) score on admission and Rankin Scale (RS) score at 30 days. Results —Interpretable CASL-PI images were obtained in all patients. Perfusion deficits were consistent with symptoms and/or diffusion-weighted imaging abnormalities. Eleven patients had hypoperfusion, 3 had normal perfusion, and 1 had relative hyperperfusion. Perfusion/diffusion mismatches were present in 8 patients. Delayed arterial transit effect was present in 7 patients; serial imaging in 2 of them showed that the delayed arterial transit area did not succumb to infarction. CBF in the affected hemisphere correlated with NIHSS and RS scores ( P =0.037 and P =0.003, Spearman rank correlation). The interhemispheric percent difference in middle cerebral artery CBF correlated with NIHSS and RS scores ( P =0.007 and P =0.0002, respectively). Conclusions —CASL-PI provides rapid noninvasive multislice imaging in acute ischemic stroke. It depicts perfusion deficits and perfusion/diffusion mismatches and quantifies regional CBF. CASL-PI CBF asymmetries correlate with severity and outcome. Delayed arterial transit effects may indicate collateral flow.
How to Advance Human Rights without Really Trying: An Analysis of Nongovernmental Tribunals

Statements such as Trotsky's have been frequent at the scores of nongovernmental tribunals held in the twentieth century. Included among the accused have been the American, Soviet, Chinese, German, and Philippine governments, multinational corporations, and international financial institutions. While maintaining a focus on war crimes, nongovernmental tribunals have also condemned a full range of violations of civil, political, and economic rights.2 The tribunals, of which the best known are the Russell Tribunals, Permanent Peoples' Tribunal, and International Sakharov Hearings, were described in the Handbook for the Russell Tribunal on the Rights of American Indians as "international colleges consisting of well-known persons . [which] do not have legal power, but aim at contributing to the formation of international law."3 This paper is an assessment of that contribution. This analysis necessarily relies on a selective and incomplete information
Genome modification in human embryonic stem cells.

Induced pluripotent stem cell (iPSC) technology has emerged as the most promising method for generating patient-specific human embryonic stem (ES) cells and adult stem cells (Takahashi et al., 2007, Cell 131:861–872; Wernig et al., 2007, Nature 448:318–324; Park et al., 2008, Nature 451:141–146). So far, most studies of direct reprogramming have been done by using lentiviruses/retroviruses encoding the reprogramming factors. This represents a major limitation to therapeutic applications since viral integration in the host genome increases the risk of tumorigenicity, and low-level residual expression of reprogramming factors may alter the differentiation potential of the human iPSCs (hiPSCs). As a result, more attention has been paid to developing new techniques to manipulate the human genome, with the goal of making safer hiPSCs that have fewer or no lesions or alterations in the genome. Additionally, the efficiency of reprogramming and of homologous recombination in gene therapy must be improved, if iPSC technology is to be a viable tool in regenerative medicine. Here, we summarize the recent developments in human genome manipulation for generating hiPSCs and advances in homologous recombination for gene targeting. J. Cell. Physiol. 222: 278–281, 2010. © 2009 Wiley-Liss, Inc.
"Undergrad Business Program Learning Goals: Differentiation, Common Aspirations, or Cursory Cloning?"

Establishing learning goals is the first step in the assurance of learning process. Proper assessment cannot take place if appropriate learning goals are not first developed. We identified the type...
Stimulated Brillouin scattering of Gaussian beams

The characteristic of stimulated Brillouin scattering of Gaussian beams is analysed. The result displays distinct threshold and saturation of the beam, precisely in agreement with the recent experimental data reported by Aoki and Tajima.
An apparatus for phase equilibria of heavy paraffins in supercritical fluids

Phase equilibria of heavy paraffins in supercritical fluids (SCFs) have not been investigated thoroughly by conventional methods, due in part to various experimental limitations (for example, long time required to obtain a measurement and large amounts of pure solute required). This work describes an experimental technique for the rapid and accurate determination of the phase equilibrium properties of heavy saturated hydrocarbons in SCFs, utilizing a packed chromatographic column coupled with an evaporative light scattering detector (ELSD).
AMINO ACIDS DO NOT SUPPRESS PROTEOLYSIS IN PRETERM NEONATES. • 1413

We have recently demonstrated dose dependent suppression of proteolysis with graded amino acid (aa) infusion in healthy term neonates (Am J Physiol, 1997). Rates of proteolysis are higher in preterm individuals, perhaps related to a greater need for aa supply for tissue remodeling and rapid growth. We hypothesized that preterm neonates would be resistant to suppression of proteolysis in response to aa infusion. To assess this, we measured the endogenous rates of appearance (Ra) of the essential aa's leucine (LEU) and phenylalanine (PHE) (reflecting proteolysis), LEU oxidation (LEU OX) and phenylalanine hydroxylation (PHE OH) (reflecting irreversible losses), and utilization of LEU and PHE for protein synthesis (PS) in 7 clinically stable preterm infants (32±0.5 wks gestation, 1.5±0.1 kg birth wt, 1.4±0.1 kg study wt, 6±1 days of age) during a basal glucose infusion (6mg/kg/min) and in response to a graded infusion of aa's (Aminosyn PF-1.2 & 2.5gm/kg/day).
Diffraction gratings for compact integrated optical structures

Diffraction gratings used in various applications for compact optical devices. We used different technologies for this task: deep-UV lithography, FIB milling, e-beam lithography, and hot embossing/nanoimprinting technology. We analyzed advantages and disadvantages of each fabrication technology.
Modelling of power plant dynamics and uncertainties for robust control synthesis

Abstract This paper presents modelling of plant dynamics and uncertainties as needed for robust control synthesis of electric power generation systems under wide-range operations. Based on the fundamental laws of physics and lumped-parameter approximation, a nonlinear time-invariant model is developed in the state-space setting for a fossil fueled generating unit having the rated load capacity of 525 MW. The modelling objective is to evaluate the overall plant performance and component interactions with sufficient accuracy for control synthesis rather than to describe the microscopic details occurring within individual components of the plant. Uncertainties in plant modelling, resulting from the conceivable sources, are then identified and quantified. These uncertainties and the desired plant performance specifications are, in turn, represented by appropriate transfer matrices in the setting of H ∝ -based structured singular value (μ). The results of simulation experiments demonstrate that a robust feedforward-feedback control policy satisfies the specified performance requirements of power ramp up and down in the range of 40–100% load under nominal conditions of load following operations.
Judging Books by Their Covers: Managing the Tensions between Paperback and Clothbound Purchases in Academic Libraries

Book purchases are a significant portion of an academic library's budget. Selecting paperback rather than hardback editions can stretch collection development dollars. This study examines the collection development statements of forty-six academic libraries regarding the selection of paperback editions. Some libraries provide vague guidance, while others identify specific price differentials between the costs of paperback and hardback editions as a decision criterion. A new method of using price difference ratios is proposed and tested using four academic disciplines. The results suggest that libraries using such ratios can achieve greater control over costs while meeting collection development goals.