cssi/SciSciGPT-SciSciNet huggingface dataset:
Safety Analysis of Trailing Cables Used on 2400-V Continuous Mining Machines

An analysis was performed to determine whether an increased shock hazard occurs with 2400-V continuous-miner trailing cables, as compared with those used with existing low and medium-voltage systems. (It should be noted that the Code of Federal Regulations defines low-voltage, medium-voltage, and high-voltage for mine power systems as 0 - 660 V, 661 - 1000 V, and greater than 1000 V, respectively). The study assumed that Mine Safety and Health Administration's Proposed Rule for High-Voltage Continuous Mining Machines was implemented with the exception of the special cable- handling requirements. Two major differences between the high-voltage proposed rule and existing low and medium-voltage regulations that are relevant to this study deal with ground-fault protection and include: (1) The maximum ground-fault current of the 2400-V system must be limited to 0.5 A, while the low and medium- voltage systems typically use a limit of 15 A, and (2) The maximum ground-fault pickup of the 2400-V system must be set at 0.125 A with a maximum time delay of 0.05 s; whereas, low and medium-voltage systems require an instantaneous pickup set at, or below, 40% of the maximum ground-fault current (6 A for 15-A systems). Results of the study show that the 2400-V trailing cable, in conjunction with the strict ground-fault protection requirements and enhanced cable construction, provide a higher level of safety compared with the trailing cables used on low and medium-voltage continuous miners.
Parent-Specific Complementary Patterns of Histone H3 Lysine 9 and H3 Lysine 4 Methylation at the Prader-Willi Syndrome Imprinting Center

The Prader-Willi syndrome (PWS)/Angelman syndrome (AS) region, on human chromosome 15q11-q13, exemplifies coordinate control of imprinted gene expression over a large chromosomal domain. Establishment of the paternal state of the region requires the PWS imprinting center (PWS-IC); establishment of the maternal state requires the AS-IC. Cytosine methylation of the PWS-IC, which occurs during oogenesis in mice, occurs only after fertilization in humans, so this modification cannot be the gametic imprint for the PWS/AS region in humans. Here, we demonstrate that the PWS-IC shows parent-specific complementary patterns of H3 lysine 9 (Lys9) and H3 lysine 4 (Lys4) methylation. H3 Lys9 is methylated on the maternal copy of the PWS-IC, and H3 Lys4 is methylated on the paternal copy. We suggest that H3 Lys9 methylation is a candidate maternal gametic imprint for this region, and we show how changes in chromatin packaging during the life cycle of mammals provide a means of erasing such an imprint in the male germline.
American Trade Policy, 1923-1995:

Preface Background to the Hawley-Smoot Tariff The Hawley-Smoot Tariff The Building of a Liberal Trade Policy The Trade Expansion Act and the Kennedy Round The Trade Reform Act and the Tokyo Round Fair Trade and the Uruguay Round The North American Free Trade Agreement A Return to Unilateralism Bibliography Index
Stretch of the Minimally Invasive Incision during Thyroid and Parathyroid Surgery

ObjectiveIdentify and quantify changes in length of the skin incision following minimally invasive thyroid and parathyroid surgery and determine whether these changes persist postoperatively.Study DesignCohort study.SettingTertiary care teaching hospital.Subjects and MethodsBetween July 2012 and June 2013, a prospective, nonrandomized study was performed on 44 consecutive patients undergoing open cervical minimally invasive thyroidectomy (incision approximately 6 cm or less) or minimally invasive parathyroidectomy (incision approximately 3 cm or less). Incision length was measured following initial incision, immediately after wound closure, and on postoperative follow-up at 2-week and 14-week visits.ResultsThirty-one patients underwent minimally invasive thyroidectomy or parathyroidectomy with initial incision lengths ranging from 20 mm to 60 mm. Seven patients (21%) underwent total thyroidectomy with a mean length of 45 ± 8 mm, 15 patients (44%) underwent unilateral thyroid lobectomy with a mean length o...
Ca2+ -induced tropomyosin movement in scallop striated muscle thin filaments.

Abstract Striated muscle contraction in most animals is regulated at least in part by the troponin–tropomyosin (Tn-Tm) switch on the thin (actin-containing) filaments. The only group that has been suggested to lack actin-linked regulation is the mollusks, where contraction is regulated through the myosin heads on the thick filaments. However, molluscan gene sequence data suggest the presence of troponin (Tn) components, consistent with actin-linked regulation, and some biochemical and immunological data also support this idea. The presence of actin-linked (in addition to myosin-linked) regulation in mollusks would simplify our general picture of muscle regulation by extending actin-linked regulation to this phylum as well. We have investigated this question structurally by determining the effect of Ca2+ on the position of Tm in native thin filaments from scallop striated adductor muscle. Three-dimensional reconstructions of negatively stained filaments were determined by electron microscopy and single-particle image analysis. At low Ca2+, Tm appeared to occupy the “blocking” position, on the outer domain of actin, identified in earlier studies of regulated thin filaments in the low-Ca2+ state. In this position, Tm would sterically block myosin binding, switching off filament activity. At high Ca2+, Tm appeared to move toward a position on the inner domain, similar to that induced by Ca2+ in regulated thin filaments. This Ca2+-induced movement of Tm is consistent with the hypothesis that scallop thin filaments are Ca2+ regulated.
Not in my hospital: Karimojong indigenous healing and biomedicine

Abstract This article presents data collected over 10 months of ethnographic fieldwork in 2006–2007 on the interactions between users of Karimojong indigenous medicine and biomedicine. The Karimojong agropastoralists live in northeast Uganda and rely on local healers to treat illness, bless pending cattle raids, and maintain the spiritual health of communities. Indigenous practice has incorporated various biomedical insights, but the Western-based health sector has not as readily welcomed Karimojong local healing as a viable therapeutic strategy forcing some healers to covertly work in hospitals and clinics. Their work underscores their importance to community well-being and as advocates of holistic healthcare; without them, biomedical health centers will not fully answer to the patients' needs.
Species differences and effect of incubation time on lactic streptococcal intracellular proteolytic enzyme activity.

Abstract Ruptured cells of Streptococcus lactis C2, S. cremoris ML 1 and a lactose-negative proteinase-negative (Lac-Prt) mutant of S. lactis C2 (LMO220) were fractionated into the soluble, particulate, and ribosome fractions by differential centrifugation. S. lactis C2 possessed higher activity of intracellular proteinase, alanylglycinase, particulate associated dipeptidase and ribosome associated dipeptidase than did S. cremoris ML1. LMO220 was lower in intracellular proteinase and dipeptidase activity and lower in ribosome associated dipeptidase activity than was the parent strain C2. Particulate associated dipeptidase activity was substantially higher in the mutant cells. Extending incubation times from 5 to 24 and 32h reduced intracellular proteinase and ribosome associated dipeptidase activity in S. lactis C2 and S. cremoris ML1. Soluble alanylglycinase activity and particulate associated dipeptidase activity of ML1 were reduced drastically after 24-h incubation.
Simultaneous balloonborne measurements of stratospheric water vapor and ozone in the polar regions

Vertical profiles of stratospheric water vapor and ozone were measured together at McMurdo and South Pole Stations in Antarctica, and at Kiruna, Sweden, on several occasions during the austral spring of 1990 and the boreal winter of 1991. The Antarctic data indicated that major dehydration had occurred on a continental scale over the winter stratospheric cloud formation period leaving only 2 to 3 ppmv water vapor between 11 and 19 km. Measurements before and after movement of the boundary of the polar vortex across McMurdo detected increases in both water vapor and ozone in the 17 to 20 km region. This injected layer was still observed at South Pole Station a month later suggesting continental proportions. In early November, with the vortex still intact, South Pole measurements indicated a substantial degree of inhomogeneity in both water vapor and ozone in the lower stratosphere. In comparison, stratospheric water vapor measurements in the Arctic gave values of 4 to 5 ppmv indicating the absence of the gross stratospheric dehydration effects obvious in the Antarctic, and they did not reveal significant structure except on one occasion with very cold temperatures ({minus}90C) at 25 km and nacreous cloud displays.
Fear and Anxiety in Environmental Education Programs

Abstract A growing number of environmental education organizations use outdoor adventure activities as part of their curriculum. Many of these activities can be fear-provoking and exert a tremendous influence upon the individual. These fears are both environmentally and socio/psychologically based and can be modified through participation in adventure activities. This paper describes the construct of fear, its use in outdoor environmental programs, and the results of two recent studies on fear.
Elastic and inelastic electron tunneling with the use of Si O 2 + Al O x and Al O x + Si barriers

Elastic and inelastic electron tunneling have been studied in junctions using thermally oxidized $\mathrm{Al}{\mathrm{O}}_{x}$ barriers doped with Si and ${\mathrm{SiO}}_{2}$. The effective barrier heights are systematically lowered by the addition of Si and ${\mathrm{SiO}}_{2}$, and for doping above certain levels an electric-field-induced barrier shift is observed for threshold voltages in the range 0.6 to 1.0 V. Inelastic electron tunneling (IET) spectra have been recorded for the pure $\mathrm{Al}{\mathrm{O}}_{x}+\mathrm{Si}$ and $\mathrm{Al}{\mathrm{O}}_{x}+\mathrm{Si}{\mathrm{O}}_{2}$ barriers as well as for such barriers doped with a range of aromatic ring compounds. Strong modes associated with the formation of $\mathrm{Si}\ensuremath{-}{\mathrm{H}}_{x}$ bonds are observed and in the case of molecular doping, junctions fabricated with these mixed barriers show changes in the relative intensities of IET-spectroscopy modes when compared to pure $\mathrm{Al}{\mathrm{O}}_{x}$ barriers. For very reactive molecules with high $\ensuremath{\pi}$-resonance energy a small amount of Si (\ensuremath{\le} 4 \AA{}) evaporated onto the $\mathrm{Al}{\mathrm{O}}_{x}$ forms a barrier which allows the observation of higher-energy modes such as C---H stretching modes. These are often quenched due to low-barrier effects in IET-spectroscopy junctions using only pure $\mathrm{Al}{\mathrm{O}}_{x}$ barriers. At doping levels of Si and ${\mathrm{SiO}}_{2}$ corresponding to average evaporated thicknesses greater than ~20 \AA{}, the junctions become extremely non-linear, and for bias voltages above 0.6 V they exhibit characteristics of high-voltage Fowler-Nordheim tunneling and internal field emission. The range of perturbations of the $\mathrm{Al}{\mathrm{O}}_{x}$ barrier produced by doping with Si or ${\mathrm{SiO}}_{2}$ suggests a strong modification of the surface OH groups. This in turn effects the molecular surface reaction and charge transfer associated with molecular doping.
Evidence of the direct role of dopant oxygen in high‐temperature superconductivity

Abstract The critical compositions uc of Cu‐site Ni and Zn necessary to destroy superconductivity in Nd2‐zCezCuO4, La2‐s ,Sr s CuO4, Bi2Sr2CaCu2O8, Bi1–8Pb0.2Sr2Ca2Cu3O10, YBa2Cu3O7 and YBa2Cu4O8 scale approximately exponentially with the distance of the impurity sites from the dopant oxygen in the charge‐reservoir regions of the crystals. This indicates that the superconducting condensates are primarily in the charge reservoirs, where they are directly controlled by dopant oxygen—not in the cuprate planes where they would be remotely controlled, as is assumed by all cuprate‐plane theories. The critical temperatures also show a trend with the same distance, suggesting that the transition temperature may be increased by fabricating superconductors whose charge reservoirs lie farther from the cuprate planes.
Urinary Incontinence in the Elderly

Urinary incontinence is a common clinical problem in the elderly population, and can affect men and women. Chronic incontinence can lead to impairments in overall functional status and is associated with significant negative effects on both overall and health-related quality of life. Careful clinical evaluation can be useful to differentiate among the various types of urinary incontinence, and can help to identify the potential cause of the condition. A wide variety of behavioral, pharmacologic, and surgical therapies are available to treat urinary incontinence, and these may be used alone or in combination. Treatment can help to improve or eliminate symptoms for many patients, leading to enhanced quality of life and improved functional status.
Students’ use of compliance gaining strategies with graduate teaching assistants: Examining the other end of the power spectrum

One goal of this research was to test empirically students’ perceptions of GTA (Graduate Teaching Assistant) and professor power and credibility. Overall, students perceived professors to be more credible and powerful than GTAs. However, students still perceived GTAs as being highly credible and powerful. Students also felt they have more power with GTAs than professors. A second goal of this research was to examine students as sources of power and persuasion by developing a typology of compliance‐gaining strategies students use to influence their GTAs. Importantly, students are recognized as powerful forces in the classroom. Moreover, by examining students as agents of persuasion, researchers gather a more complete picture of compliance‐gaining models.
Depression and type 2 diabetes: Cortisol pathway implication and investigational needs

Depression and type 2 diabetes (T2D) are clinically associated and the causes of the association are still under investigation. We aimed at identifying what is known about the stress response and cortisol pathway and the clinical association of depression and T2D, and at hypothesizing the link of the association. In this review, we report independent studies on stress response, cortisol pathway, depression, T2D, and independent studies on stress and cortisol pathway in depression, and in T2D. We focus and integrate the stress and cortisol pathway hypothesis to explain the clinical association of depression and T2D. We hypothesize that the corticotropin-releasing hormone receptors are one of the missing linking factor of the cortisol pathway underlying the clinical association of depression and T2D. We state what studies are still needed to confirm or rule out our hypothesis.
Kinetic Studies of Negative Ion Reactions in a Quadrupole Ion Trap: Absolute Rate Coefficients and Ion Energies

A new apparatus consisting of an ion−molecule reactor coupled to a quadrupole ion trap is described. The kinetics and products of the rapid reactions of SF6- with SO2, HNO3, and HCl in the ion trap are reported. There is excellent agreement between the ion trap rate coefficients and yields, and flowing afterglow results. Rate coefficients for reactions of products of the SF6- reactions are also reported. Measurements of the equilibrium constant for the reaction NO3-·HNO3 + HNO3 ⇄ NO3-·(HNO3)2 in the ion trap provide a very sensitive measure of the energy of the trapped ions. These measurements indicate that the effective temperature of the trapped NO3-·(HNO3)2 ion is 320 ± 30 K for an ion trap at 298 K (1−2 mTorr He, qz = 0.074). The presence of 0.2 mTorr N2 buffer gas increases the internal temperature of the trapped ions by about 10 K. The internal temperature is also a weak function of the trapping potential, increasing by about 10 K over the range 0.074 < qz < 0.286.
Synthesis of myristoyl CoA analogues and myristoyl peptides as inhibitors of myristoyl CoA: Protein N‐myristoyltransferase

□ To develop inhibitors of myristoyl CoA:protein /V-myris- toyltransferase (NMT), a series of myristoyl coenzyme A analogues and myristoyl peptides were synthesized, including S-(2-oxopentadecyl)- CoA (1), S-(2-hydroxypentadecyl)-CoA (2), S-(2-oxopentadecyl)- pantetheine (3), Myr-N-GIy-(i_)-Phe (4), Myr-N-GIy-(L)-Tyr (5), and Myr-N-GIy-(L)-Asn-Ala-Ala-Ser-Ala-Arg-(NH 2 ) (6). Biological evaluation of these compounds in an in vitro NMT enzyme assay revealed that the nonhydrolyzable acyl CoA analogue 1 was the most potent inhibitor [inhibitor dissociation constant (K I ) = 24 nM]. A preliminary structure- activity relationship study showed that the adenosine moiety and the 2-keto group in this nonhydrolyzable analogue were necessary for inhibitory activity. A possible mechanism for the inhibition of NMT by 1 was proposed, in which 1 might block the reaction at the stage of an acyl-CoA-NMT-peptide complex. Product analogues such as the myristoylated peptides 4-6 were poor inhibitors of NMT.
Molecular applications of flow cytometry

t a rge t Pr imer B re fe rence P r imer B T he detection of genetic abemations is playing a more prominent role in our understanding of disease than ever before. It is now possible to detect gene mutations, gene translocafion, gene amplification, gene deletions, and gene rearrangements with precision. In addition, the measurement of gene expression can provide a means for determining a molecular phenotype for cells. Currently most of these procedures are performed on isolated DNA or RNA where the correlation to the cells of origin cannot be identified or microscopically where the quantitative information is less reliable. Flow cytometry has the advantage of rapid cell-by-cell integration and the ability to discriminate multiple parameters simultaneously. The possibility, for example, of determining both an immunophenotype using fluorochrome-conjugated antibodies to cellular proteins and a molecular phenotype using fluorochrome-conjugated probes seems to be within our grasp. There are several approaches under development for applying flow cytometry to molecular techniques. These include sorting distinct cell populations based on immunophenotype and applying quantitative polymerase chain reaction (PCR) procedures for detection of DNA or RNA copy numbers. Only 1,000 cells are required, and correlation between the target genetic level and protein product level can be directly compared. In situ hybridization can now be reliably performed on cells attached to microscope slides or in suspension where the cells can either be viewed microscopically or analyzed by flow cytomelry. The current problem with in situ hybridization is sensitivity due to the current detection levels by flow cytometry that require an excess of 500 copies per cell. One reason for this low Figure 1. Hybrid competitive reference standard: Two competitive reference standards are first prepared having regional sequence homology with the target gene sequence of interest and a ref~ence gene sequence on the same chromosome. An SmaI restriction site is introduced using a PCR-based site-directed mutagenesis procedure. These two standards are ligated together to produce the hybrid competitive reference standard shown. Target primers A and B and refezence primers A and B are introduced for quantitation.
Signatures of universal four-body phenomena and their relation to the Efimov effect

A theoretical study predicts universal signatures of four-body physics in cold-gas experiments, and presents evidence that these have already been observed.
Examination and treatment of pediatric injuries of the hip and pelvis

Injuries to the hip and pelvis are the least common of lower extremity injuries in youth sports, but include many of the more serious conditions. This article describes the bone and soft-tissue conditions of the hip and pelvis that may present to health care providers caring for the pediatric and adolescent sporting population. The article discusses epidemiology, mechanisms, clinical presentation, evaluation, and treatment options.
Who Lost Paul Corey

Every serious reader is aware of the literary career of Herman Melville: early fame, death in obscurity in 1891, triumphant revival as a, possibly the, major American novelist in the 1920s. More recently, the serious reader learns with some shock that William Kennedy's prize winning Ironweed was turned down by thirteen publishers before finding a publisher. There is the case of John Kennedy Toole; only the fanatic persistence of his mother after his suicide found A Confederacy of Dunces first a publisher and then the Pulitzer Prize. There are a multitude of similar stories.
Seismic Detection of Fractured Reservoirs: A Case Study of a Devonian Shale Gas Field in West Virginia: ABSTRACT

Interpretation of seismic data over the Cottageville gas field in West Virginia reveals the presence of numerous changes in the amplitude and shape of reflections within the lower and middle Huron Shale. Production from the lower Huron is fracture controlled, and some of the more pronounced changes in amplitude and shape occur in the more productive areas of the field. These changes are related to the development of low-impedance intervals that extend into the middle Huron Shale. Gamma-ray logs and a velocity log from the field indicate that the basal part of the middle Huron is homogeneous in character. Changes in reflection character from this interval arise from changes in the bulk properties of the rock over an area the size of a Fresnel zone. The Fresnel zone radius t the lower Huron depth is approximately 400 ft, so changes in bulk properties of the rock over this scale may not be observable in the well bore. Reduction of the shear and bulk moduli caused by increased fracture intensity and the dependance of P-wave velocity on these properties could produce the observed changes in impedance. The organic portions of the lower Huron have been intensely fractured; however, these fractures are often closed or are partially mineral filled, so fracture related changes in P-wave velocity are less likely. Our research indicates that the fractured Devonian shale reservoir is detectable on conventional seismic data. End_of_Article - Last_Page 1451------------
Modal method by Fourier expansion for modeling crossed gratings

A new formulation of the modal method by Fourier expansion (MMFE), that uses the correct rules of Fourier factorization, for crossed surface-relief gratings is presented. By numerical examples, the new MMFE is shown to converge much faster than the old MMFE. For the first time the MMFE is used to produce convergent numerical results for metallic crossed gratings. In addition, the new formulation uses a general non-rectangular Cartesian coordinate system, which gives the MMFE greater generality and in some cases the ability to save computer memory and computation time. Two matrix truncation schemes, the customary parallelogramic truncation and a new circular truncation, are considered. Numerical experiments show that the former is superior.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
On the vibrations of overdamped systems

Abstract Vibration systems are characterized by the two parameters: ωn, the undamped natural frequency, and ζ, the damping ratio. In the case of lightly damped systems, these parameters are determined by means of the logarithmic decrement. A simple method is presented here which applies to overdamped systems, ζ>1. The method involves simple measurements, and a criterion for the accuracy of the method is given.
Extending a spectrin repeat unit. II: rupture behavior.

A spectrin repeat unit was subject to extension using cyclic expansion nonequilibrium molecular dynamics. Periodic boundary conditions were used to examine the effects of the contiguous α-helical linker on the force response. The measured force-extension curve shows a linear increase in the force response when the spectrin repeat unit is extended by ∼0.4 nm. After that point, the force response peaks and subsequently declines. The peak in the force response marks the point where the spectrin repeat unit undergoes a change in its material properties from a strongly elastic material to a mostly viscous one, on the timescales of the simulations. The force peak is also correlated with rupture of the α-helical linker, and is likely the event responsible for the peaks in the sawtooth-pattern force-extension curves measured by atomic force microscopy experiments. Rupture of the linker involves simultaneously breaking approximately four hydrogen bonds that maintain the α-helical linker. After this initial rupture, the linker undergoes simple helix-to-coil transitions as the spectrin repeat unit continues to be extended. The implications of linker rupture in the interpretation of unfolding and atomic force microscopy experiments are also discussed.
Competing adiabatic and nonadiabatic pathways in the cis–trans photoisomerization of cis-1,2-di(1-methyl-2-naphthyl)ethene. A zwitterionic twisted intermediate

Identical fluorescence lifetimes and spectra of cis- and trans-1,2-di(1-methyl-2-naphthyl)ethene reveal an adiabatic cis → trans photoisomerization pathway that accounts for a significant fraction of observed cis → trans photoisomerization quantum yields. The fluorescence quantum yields of both isomers decrease as the solvent is changed from methylcyclohexane to the more polarizable toluene or to the more polar acetonitrile and there is a corresponding increase in the photoisomerization quantum yield in the trans → cis direction. The pronounced solvent dependence of the contribution of the adiabatic pathway to cis → trans photoisomerization – methylcyclohexane (70%), toluene (45%), acetonitrile (31%) – is consistent with the participation of a zwitterionic twisted intermediate, 1p*, on the singlet excited state surface which is stabilized as the polarizability and/or polarity of the solvent is increased. Solvent stabilization of 1p* favours the nonadiabatic photoisomerization pathways of both isomers and diminishes the cis → trans adiabatic pathway.
The Impact of SOA Implementation on IT-Business Alignment: A System Dynamics Approach

With firms facing intense rivalry, globalization, and time-to-market pressures, the need for organizational agility assumes greater importance. One of the primary vehicles for achieving organizational agility is the use of agile information systems [IS] and the close alignment of information technologies [IT] with business. However, IS is often viewed as an impediment to organization agility. Recently, service-oriented architecture [SOA] has emerged as a prominent IS agility-enhancing technology. The fundamental question of how SOA can enhance organization agility and foster closer alignment between IT and business has not been adequately addressed. The dynamic interaction among external business environmental factors, organizational agility, and IS architecture makes the process of keeping IT and business aligned more complex. This study uses a design science approach to build a system dynamics model to examine the effect of employing alternative SOA implementation strategies in various organizational and external business environments on the IT business alignment and IS cost. The results provide insights into the shaping of IT-business alignment. Additionally, the system dynamics model serves as a tool for supporting managerial decisions related to SOA implementation.
Putting the brake on drive: meiotic drive of t haplotypes in natural populations of mice

Abstract Mouse t haplotypes are a `selfish' form of chromosome 17 that show non-mendelian transmission from heterozygous +/t males. The considerable transmission bias in favour of t haplotypes should result in very high frequencies of these chromosomes in natural populations, but they seldom occur at the high frequencies expected. Recent research on this and other meiotic drive systems has shown how a variety of mechanisms have evolved to suppress drive, and to re-establish mendelian segregation.
Symptom Profile of ADHD in Youth With High-Functioning Autism Spectrum Disorder: A Comparative Study in Psychiatrically Referred Populations.

Objective: To compare the clinical presentation of ADHD between youth with autism spectrum disorder (ASD) and ADHD and a sample of youth with ADHD only. Method: A psychiatrically referred sample of...
Dimeric products from the dissolving metal reduction of camphor

Abstract Various dissolving metal reductions of (+)-camphor afford one of two pinacols frequently accompanied by a dimeric product in which one bicycloheptane unit has been cleaved. Similar reductions of (±)-camphor afford various mixtures of (±)- exo - endo , (±)- endo - endo and meso endo - endo pinacols. The structures of two of these products were confirmed by X-ray crystallography.
Age Constraints on the Duck Ponds and Limeburner's Point Mammalian Faunas Based on Magnetic Polarity Stratigraphy in the Geelong Area (Victoria), Australia

Abstract New magnetostratigraphic results may be used to determine the age of two locally important fossil vertebrate faunas near Geelong (Victoria), Australia. Paleomagnetic samples collected from sections located at Limeburner's Point and Limeburner's Bay, together with previously suggested stratigraphic correlations, now constrain the age of the Duck Ponds Local Fauna to be younger than 1.66 myr (and probably greater than 0.98 myr) and the age of the Limeburner's Point Local Fauna to be younger than 0.98 myr. These age determinations enhance the biostratigraphic importance of both local faunas on a continent characterized by a chronic lack of chronologically well-constrained fossil vertebrate localities.
Surface diffusion of In on Ge(111) studied by optical second harmonic microscopy

Surface diffusion of In on Ge(111) has been measured by optical second harmonic microscopy. This technique employs surface second harmonic generation to directly image submonolayer surface concentration profiles. The coverage dependence of the diffusivity D can then be obtained from a Boltzmann–Matano analysis. In the coverage range 0.1<θ<0.48, the activation energy Ediff decreased with increasing coverage, ranging from 31 kcal/mol at θ=0.1 to 23 kcal/mol at θ=0.48. Over the same coverage range, the pre‐exponential factor D0 decreased from 5×102 to 1×10−1 cm2/s. This gradual change reflects a change in diffusion mechanism arising from the disordered nature of the Ge(111) surface. At low coverages, In adatoms sink into the top layer of Ge, and diffusion is dominated by thermal formation of adatom‐vacancy pairs. At high coverages, diffusion occurs by normal site‐to‐site hopping. The gradual change in diffusion parameters with coverage was interrupted by an apparent phase transition at θ=0.16. At this point,...
Intramolecular general acid catalysis of the hydrolysis of 2-(2'-imidazolium)phenyl phosphate, and bond length-reactivity correlations for reactions of phosphate monoester monoanions.

Rate constants for the hydrolysis of 2-(2‘-imidazolium)phenyl hydrogen phosphate (IMPP) in water at pH < 6 indicate that activation by the imidazolium moiety disappears with the deprotonation of the phosphate group, and the reaction involves the hydrogen-bonding of the imidazolium NH with the aryl oxygen leaving group. The reaction should involve a near-planar conformation of the imidazolium and the phenyl groups in the activated complex, which favors proton-transfer. The crystal structure of IMPP was solved, and a bond length−reactivity correlation for reactions of phosphate monoester monoanions is described.
Separate conflict-specific cognitive control mechanisms in the human brain

To ensure optimal task performance, the human brain detects and resolves conflict in information processing via a cognitive control system. However, it is not known whether conflict resolution relies on a single central resource of cognitive control, or on a collection of independent control mechanisms that deal with different types of conflict. In order to address this question, we assessed behavioral and blood-oxygen-level-dependent (BOLD) responses during the simultaneous detection and resolution of two sources of conflict in a modified color-naming Stroop task: conflict stemming from incompatibility between the task-relevant and an irrelevant stimulus feature (stimulus-based or Stroop conflict), and conflict stemming from incompatibility between an irrelevant stimulus feature and response features (response-based or Simon conflict). Results show that control mechanisms recruited by stimulus-based conflict resolve stimulus-based conflict, but do not affect the resolution of response-based conflict, and vice versa. The resolution of response-based conflict was distinguished by modulation of activity in premotor cortex, whereas resolution of stimulus-based conflict was distinguished by the modulation of activity in parietal cortex. These results suggest that the human brain flexibly adopts, and independently controls, conflict-specific resolution strategies, biasing motor programming to resolve response-based conflict, and biasing stimulus representations to resolve stimulus-based conflict. We propose a non-centralized, modular architecture of cognitive control, where separate control resources operate in parallel, and are recruited in a context-sensitive manner.
Measuring immunization coverage.

Abstract Objective: Information about immunization coverage comes from five major sources: the National Immunization Survey, the National Health Interview Survey, retrospective school-entry surveys, the Health Plan Employer Data and Information Set (HEDIS) measures reported by managed care plans, and assessments performed on clinics and private practices. In this article, we describe the methodology of the major surveys, discuss technical and policy issues in measuring immunization coverage, and identify issues that must be addressed to harmonize immunization rates calculated from different sources. Methods and Topics: We describe the (1) design and methodology of the five major sources of immunization coverage assessments, (2) issues and controversies in measuring immunization coverage, and (3) preliminary efforts to harmonize calculation of immunization coverage. Technical and policy issues involve dose and interval requirements, which vaccines are included in the series-completion calculations, and who is excluded from each method of calculation. Conclusions: The purpose of measuring up-to-date immunization coverage determines the way that it is measured. The tension between measuring immunization coverage to monitor population protection against disease and measuring immunization coverage to determine how well the health care delivery system is working leads to different ways of selecting a sample and reporting coverage. These differences create confusion for the public policymakers who try to identify problems and to set priorities for immunization efforts. Although some unavoidable differences may occur because of differences in purpose of the measurement, greater harmonization is possible.
Dr. Lewin's Little Liver Patties: A Parable About Encouraging Healthy Lifestyles

The title for this paper, as it appeared in the official program, had nothing whatsoever to do with the actual content. It was assigned by the Program Cornrnittee when they were having a "Rocky Mountain H igh on creative speculationand I simply was too slothful to request a change. With my apology for that error of omission, a more appropriate title appears above. As a further preface, I wish to acknowledge my appreciation to the presenters who, despite formidable burdens and impediments of all sorts, delivered draft copies of their papers to me by express mail and fax to my office and residence, as well as by nocturnal delivery under the door of my room in the hotel at Vail. It always is a special privilege to review such documents in advance of their delivery. I found the 1995 collection of Academy papers highly informative, often engrossing, and, without exception, worthy of attention and comment. My only regret is that it will be impossible here to give each one the full honor it deserves.
Silica nanoparticle metrology using Ursa Blue™ and colloidal Ludox solutions

Abstract We report spectroscopic properties of a new nanoparticle sizing fluorophore and demonstrate its applicability to characterize silica particles in colloidal solutions using steady-state anisotropy measurements and Perrin graph analysis. The strong electrostatic interaction between the cationic particle sizing fluorophore and the SiO2 surface is demonstrated by comparing data to that recorded for the anionic fluorophore fluorescein. The Perrin analysis reports a mean particle radius of 6.35 nm, which is larger than the manufacture specified radius of 3.5 nm, possibly indicating a degree of aggregation of the particles. The anionic fluorophore fluorescein shows no interaction with the SiO2 surface, and reports a hydrodynamic radius of 0.40 nm. We thus speculate that fluorescein can be used as an internal microviscosity probe for colloidal silica systems. The intensity averaged fluorescence lifetime of the particle sizing fluorophore and fluorescein are approximately 16 ns and 4 ns, respectively.
Light emission in the channel region of a polymer thin-film transistor fabricated with gold and aluminum for the source and drain electrodes

Abstract Light emission in the channel region of a thin-film transistor using the semiconducting polymer Super Yellow as the emissive material is reported The transistor structure was fabricated with light emission as the goal. To accomplish this, gold, which is a good hole injector into the organic layer, was patterned for one electrode, while aluminum, which has been shown to function as an electron injecting contact in sandwich and planar organic light emitting diodes, was patterned for the other electrode. The channel length was ∼1 micrometer and the channel width was −4000 micrometers. The data demonstrate that the magnitude of the gate bias influences the brightness of the emission zone. The location of the emission zone and the possible mechanism of operation will be discussed.
Tourism and development in Tunisia

Abstract Economic liberalization policies, externally imposed structural requirements, and Tunisia's comparative advantage have led the government to pursue tourism on a large scale. The growth of this sector has been phenomenal as evidenced by large scale hotel resort enclaves for Europeans and supportive infrastructural commitments by government and the private sector. The economic impact has been impressive in deficit reduction, capital accumulation, and balance of trade, but shows a vulnerability to the vicissitudes of international events. Despite economic gains, Tunisian policymakers are faced with cost/benefit ratio decision due to social and environmental impacts and the clash between Islamic and European values.
Estimated Number of Preterm Births and Low Birth Weight Children Born in the United States Due to Maternal Binge Drinking

The objective of this study was to estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. To estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. A simulation model was developed to estimate the number of PTB and LBW cases due to maternal binge drinking. Data inputs for the model included number of births and rates of preterm and LBW from the National Center for Health Statistics; female population by childbearing age groups from the U.S. Census; increased relative risks of preterm and LBW deliveries due to maternal binge drinking extracted from the literature; and adjusted prevalence of binge drinking among pregnant women estimated in a multivariate logistic regression model using Behavioral Risk Factor Surveillance System survey. The most conservative estimates attributed maternal binge drinking to 8,701 (95 % CI: 7,804–9,598) PTBs (1.75 % of all PTBs) and 5,627 (95 % CI 5,121–6,133) LBW deliveries in 2008, with 3,708 (95 % CI: 3,375–4,041) cases of both PTB and LBW. The estimated rate of PTB due to maternal binge drinking was 1.57 % among all PTBs to White women, 0.69 % among Black women, 3.31 % among Hispanic women, and 2.35 % among other races. Compared to other age groups, women ages 40–44 had the highest adjusted binge drinking rate and highest PTB rate due to maternal binge drinking (4.33 %). Maternal binge drinking contributed significantly to PTB and LBW differentially across sociodemographic groups.
Evidence for independent motional processes on the two interstitial sublattices of a layer-structured metal hydride: hydrogen spin-lattice relaxation and motional narrowing in zirconium monohalide hemihydrides, ZrXH/sub 0. 5/

We report the results of a proton-magnetic-resonance investigation of hydrogen location and motion in the hemihydrides $\mathrm{Zr}X{\mathrm{H}}_{0.5}$ of the metallic layer-structured monohalides $\mathrm{Zr}X$ of zirconium ($X=\mathrm{B}\mathrm{r},\mathrm{C}\mathrm{l}$). Wide-line and pulsed NMR methods were employed to measure the temperature dependence of the linewidth and second moment and of the spin-lattice relaxation time in the laboratory and rotating frames. The results indicate that hydrogen forms an ordered structure on the tetrahedral ($T$) interstitial sublattice within the Zr metal bilayers, with some (small) random occupancy of octahedral ($O$) sites. Two stages of motional narrowing observed in the wide-line measurements and double minima found in the relaxation times are consistent with the occurrence of essentially independent hydrogen motional processes on the $T$ and $O$ interstitial sublattices. Hydrogen site occupancy probabilities, jump frequencies, activation energies for hydrogen diffusion, and conduction-electron contributions to the proton spin-lattice relaxation rate are deduced from the measurements.
Segmented Reinforcement Variable Stiffness Materials for Reconfigurable Surfaces

Reconfigurable and morphing structures may provide a range of new functionalities such as optimization over broad operational conditions and multi-mission capability. This article introduces a new generic approach to achieving large strains in materials with high elastic moduli (5-30 GPa). The work centers on creating variable stiffness composite materials which exhibit a controllable change in elastic modulus (bending or axial) and large reversible strains (5-15%). We have performed a simulation study to better understand the implication of various geometric design parameters on the elastic and deformation behavior. Using this information, a series of prototype materials were prepared using a commercial shape memory polymer, and measurements on these materials indicate a controllable change in stiffness as a function of temperature with large reversible strain accommodation. We have fabricated and tested several design variations of laminar morphing materials which exhibit structural stiffness values of ...
4573 Endoscopic ultrasound-guided fine needle aspiration in the staging of rectal cancer.

Background: EUS has an established role in the preoperative staging of rectal cancer. Prior studies report EUS tumor staging accuracy ranging from 69%- 85% and nodal staging accuracy from 60%-79%. The utility of EUS-guided FNA in staging rectal cancer has not been previously reported. Methods: From 4/95- 8/99, 51 patients with rectal cancer underwent EUS evaluation. EUS was performed using the Olympus echoendoscope (GF-UM20 or 130) and EUS-guided FNA with the Pentax echoendoscope (PG-32UA or 36UX) and the GIPMediglobe needle or the Wilson-Cook needle. Of the 51 patients, 15 had EUSguided FNA of perirectal nodes. Of the 51 patients, 45 underwent surgery and pathologic correlation was available. Data was analyzed using the Fisher's exact test. Results: Staging accuracy was based on histopathological specimens obtained from surgery. The EUS T stage was accurate in 36 of 45 patients (80%). The 9 patients inaccurately staged were all overstaged. The use of EUSguided FNA increased the nodal staging accuracy of EUS alone. EUS and EUSguided FNA facilitated neoadjuvant therapy in 22 of the 51 patients evaluated. Conclusions: EUS-guided FNA is superior over EUS alone in nodal staging of rectal cancer. EUS-guided FNA has an overall nodal staging accuracy rate of 87% (p
Electron impact excitation of the resonance transitions of highly ionized atoms of the Be-, Mg-, and Zn-isoelectronic sequences

Abstract Electron impact excitation collision strengths for the ns21S - nsnp1P resonance transitions of highly ionized Be, Mg, and Zn-like ions have been computed in the distorted wave approximation, including the effects of exchange and target state correlation. Good agreement is observed between these data and collision strengths computed in the Coulomb-Born and Born approximations at high incident energies. Analytic fits to the distorted wave data are presented.
Isolation and characterization of epidermal growth factor from human milk

Epidermal growth factor (EGF) has been purified from human milk. The purification was monitored with a human placental membrane radioreceptor assay using murine salivary epidermal growth factor I (mEGF I) as a competitive ligand and was achieved exclusively by the use of reverse-phase liquid chromatography (RPLC). The sequential use of preparative, semipreparative and analytical RPLC on an octylsilica support with solvent systems of different solute selectivity such as pyridine formate, triethylammonnium phosphate or perfluorocarbonic acids in the presence of n-propanol or acetonitrile allowed purification to homogeneity with 5 consecutive runs. The molecular mass, amino acid composition and NH2-terminal sequence of human EGF were determined. Gas-phase microsequencing of residues 1-17 revealed the following sequence: Asn -Ser-Asp-Ser-Glu-X-Pro-Leu-Ser-His-Asp-Gly-Tyr-X-Leu-X-Asp which is identical with the NH2-terminof urogastrone from human urine. The purified polypeptide competes with mEGF for the placental membrane receptor with a ki, of 1 ng. Furthermore, it stimulates the anchorage-dependent as well as -independent proliferation of human and rat indicator cells with half-maximal stimulation at 1 and 2.5 ngml, respectively. Although human epidermal growth factor has been unequivocally identified in human milk and - for the first time - shown to be identical with urogastrone from human urine, the high-resolution techniques employed have also revealed the presence of EGF-related molecules which await further characterization. It is possible that EGF and the EGF-related growth factors possess important regulatory functions in normal growth of the human breast during pregnancy and lactation as well as in abnormal growth during mammary tumor formation and progression.