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Eleocharis elegans, a neotropical wetland sedge (Cyperaceae), is reported as new for the United States from a site in Hardee County, Florida. A number of factors suggest this represents a natural occurrence. We speculate that climate change-related factors such as increasingly frequent major storms offer the most logical explanation of its arrival in the United States.

Islands are highly variable in size, shape, elevation, and climate let alone in terms of culture, social, and economic characteristics. Islands and their populations are likely to experience a wide range of changes during the Anthropocene. Nevertheless, the effects of climate change are likely to be widely felt across the region. Vulnerability of Pacific islands will reflect social changes resulting from a century or more of colonization and globalization. Many practices that enabled Pacific island populations to thrive have been lost. Adaptation costs are likely to be extremely high and beyond the resources of most PICTs.

The present empirically examined customer satisfaction with Internet sites that vary in the opportunity for mass customization. The expectation–disconfirmation model was used as a theatrical framework of the study. Two children's apparel sites were developed as the stimuli: one with a mid level of interactivity and the other with a high level of interactivity, for selection of clothing design options. The data from 208 respondents were analyzed using LISREL 8.72. The finding indicates that both consumers' expectations and perceived performances for the mass customized sites included positive and negative aspects. The results suggest that expectations were not a significant predictor of satisfaction for this innovative shopping experience yet satisfaction was primarily driven by the performance of the site and predicted by disconfirmation of expectations. The findings also suggest that expectations are not related to performance perceptions, possibly due to consumers' lack of familiarity with mass customization. The more interactive site yielded the more positive performance as well as overall positive satisfaction. Nevertheless, the less interactive site, which offers fewer choices than more interactive site, yielded more positive behavioural consequences. The generalization of the results of this study is limited because of lack of random sampling and use of the mock site of children's apparel product category. However, useful theoretical and managerial implications are discussed.

The Southern Alps of New Zealand is an active oblique collisional mountain belt with extensive regional tectonically driven fluid flow. There is no evidence for igneous activity, and fluids consist of varying proportions of meteoric water and mid-crustal fluid derived from dehydration reactions. Fluid flow is controlled by fracture porosity, particularly in damage zones along faults and fault intersections. Gold and arsenic bearing veins exposed at the surface indicate two principal zones of gold mineralisation at depth. One of these is in the highest mountains, near to, but not in the region of maximum uplift. Deformation is dominated by reverse faulting, but some normal and strike-slip faults occur as well. The other zone of gold mineralisation is at and near the intersection of regional oblique dextral reverse faults and regional strike-slip faults. Both zones are characterised by small discontinuous vein systems, locally accompanied by ankeritic alteration of host rock. Veins occur in extensional and shear veins, and in dilational jogs with implosion breccias. Gold mineralisation occurred at many structural levels between the brittle–ductile transition and the near-surface region. The Southern Alps hydrothermal system represents an active roof zone to a mesothermal gold deposition system at depth. As such, this is a modern analogue for mesothermal gold terranes elsewhere in New Zealand and around the world. Observations on the regional distribution of fluid flow in active orogens can give insights into fluid flow at depth where gold mineralisation is occurring now. Comparison of these observations with ancient gold-bearing belts allows construction of three-dimensional concepts of orogenic fluid flow and gold mineralisation.

A new Q–Q-Clamshell magnetic spectrometer called SASP has been commissioned in the proton hall at TRIUMF. The principal optical characteristics are: a solid angle acceptance of 13.5 msr, a momentum bite of 25%, a momentum resolution of Δ p / p =2×10 −4 , and a maximum central momentum of 720 MeV/ c . We describe the optical design, the magnetostatic design, the magnetic field mapping procedure, and the performance of this instrument.

Tensor moments t kq have been determined for the 6 Li ∗ (2.186 MeV, 3 + ) state produced in the 9 Be(p,α 1 ) 6 Li reaction at 40 MeV. Angular correlation measurements were made between α 1 and the α-particle or deuteron fragment from the breakup of 6 Li ∗ . Comparison of the t kq are made with the predictions of a model that includes direct and exchange processes. Angular distributions of the differential cross sections for the 9 Be(p,α) 6 Li reaction for the g.s. and first two excited states are presented.

Properties of the TRIUMF neutron beam (4A2) are presented and compared with a Monte Carlo prediction. The beam intensity profile, energy spectrum and polarization are predicted taking into account the beamline geometry, energy losses in the LD2 production target, the properties of the pd → npp reaction, and the scattering of neutrons from the collimator walls. The results allow for improved corrections to systematic errors in a number of TRIUMF neutron experiments.

Charge symmetry breaking in np elastic scattering at 347 MeV has been measured with high precision. From fits of the measured asymmetry curves over the angular range 53.4{degree} {le} {theta}{sub cm} {le} 86.9{degree}, the difference in the center-of-mass zero-crossing angles of the analyzing powers was determined to be 0.438{degree} {+-} 0.054{degree} (stat.) {+-} 0.051{degree} (syst.). Using the experimentally determined slope of the analyzing power, dA/d{theta} = ({minus}1.35 {+-} 0.05) {times} 10{sup {minus}2} deg{sup {minus}1}, this is equivalent to {Delta}A = [59 {+-} 7(stat.) {+-} 7(syst.) {+-} 2(syst.)] {times} 10{sup {minus}4}. Predictions of nucleon-nucleon interaction models based on meson exchange agree well with this result.

We have measured the relative differential cross section and spin observables for the reaction {ital np}{r_arrow}{ital pp}{pi}{sup {minus}} at 443 MeV. Our measurements have been compared with predictions of the model of Kloet and Lomon. Some of the variables show marked disagreement with predictions; for other variables there is surprisingly good agreement.

Angular distributions of the differential cross sections and analyzing powers have been measured for the [sup 3]He([ital [rvec p]],[pi][sup +]) [sup 4]He and [sup 4]He([ital [rvec p]],[pi][sup +])[sup 5]He reactions at proton bombarding energies between 240 and 507 MeV. These new results provide a comprehensive set of data spanning the region of the [Delta][sub 1232] resonance and are compared with a phenomenological model that incorporates the amplitudes for the [ital pp][r arrow][ital d][pi][sup +] reaction, and with calculations from a microscopic ([ital p],[pi][sup +]) model. A [sup 5]He final state interaction calculation based upon the low energy [ital n]+[alpha] elastic phase shifts indicates that the [sup 4]He([ital p],[pi][sup +])[sup 5]He spectra are nearly independent of pion angle and proton energy. Comparisons made with the time reversed charge symmetric reaction [sup 3]H([ital n],[pi][sup [minus]])[sup 4]He reaction indicate substantial Coulomb effects are still present at 300 MeV.

Nanoscale protein tubules called rhapidosomes, approximately 17 nm in diameter and 400 nm in length, isolated and purified from the bacterium Aquaspirillum itersonii, were metallized with nickel by an electroless plating technique using molecular catalysts, instead of using the more traditional colloidal catalysts approach. It is demonstrated that surface amino acids can initiate the catalyzation process of electroless metallization using molecular catalyst particles. Results of characterization of metallized rhapidosomes by transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) are discussed.

At TRIUMF we are measuring charge symmetry violation in np elastic scattering. If charge symmetry holds the analyzing powers A n and A p are equal. The measurements will therefore determine the difference from zero of ΔA ≡ A n − A p . The measurements are carried out in the vicinity where the analyzing powers cross zero in order to minimize systematic errors. A 350 MeV polarized ( P n ≅ 0.5) or unpolarized neutron beam is incident onto respectively an unpolarized or polarized ( P p ≅ 0.65) target of the butanol frozen spin type. A symmetric (about the beam axis and in the scattering plane) system of proton detectors and neutron arrays records neutron-proton coincidence events. The detection system allows measurements in the centre-of-mass angular range of 50°–90°.

An outline is given of an experiment to measure parity violation in p-p scattering at 230 MeV at TRIUMF. The parity-violating longitudinal analysing power A z will be measured to a precision of 2×10 −8 and will isolate the parity-violating 3 P 2 − 1 D 2 partial wave amplitude.

Two dual function intensity profile monitors have been designed for a measurement of parity violation in p -p scattering at about 230 MeV using longitudinally polarized protons. Each device contains a set of split secondary electron emission (SEM) foils to determine the median of the beam current distribution (in x and y). The split foils, coupled through servoamplifiers and operational amplifiers to upstream aircore steering magnets, have demonstrated the ability to hold the beam position stable to ±5 μm for beam position fluctuations up to 1000 Hz. These monitors also contain a set of foil strip planes giving information on the intensity distribution projected onto the two orthogonal axes, x and y. Data were acquired using 0.008 mm thick, 0.90 mm wide aluminum foil strips at 1.00 mm centers. The foil strip planes were able to determine the beam centroid to within ±3 μm after one hour of data taking with a 100 nA, 15 mm FWHM Gaussian beam.

Recently, high-level features such as word idiolect, pronunciation, phone usage, prosody, etc., have been successfully used in speaker verification. The benefit of these features was demonstrated in the NIST extended data task for speaker verification; with enough conversational data, a recognition system can become "familiar" with a speaker and achieve excellent accuracy. Typically, high-level-feature recognition systems produce a sequence of symbols from the acoustic signal and then perform recognition using the frequency and co-occurrence of symbols. We propose the use of support vector machines for performing the speaker verification task from these symbol frequencies. Support vector machines have been applied to text classification problems with much success. A potential difficulty in applying these methods is that standard text classification methods tend to "smooth" frequencies which could potentially degrade speaker verification. We derive a new kernel based upon standard log likelihood ratio scoring to address limitations of text classification methods. We show that our methods achieve significant gains over standard methods for processing high-level features.

TRIUMF experiment 497 has measured the parity violating longitudinal analyzing power, A_z, in pp elastic scattering at 221.3 MeV incident proton energy. This paper includes details of the corrections, some of magnitude comparable to A_z itself, required to arrive at the final result. The largest correction was for the effects of first moments of transverse polarization. The addition of the result, A_z=(0.84 \pm 0.29 (stat.) \pm 0.17 (syst.)) \times 10^{-7}, to the pp parity violation experimental data base greatly improves the experimental constraints on the weak meson-nucleon coupling constants h^{pp}_\rho and h^{pp}_\omega, and has implications for the interpretation of electron parity violation experiments., Comment: 17 pages RevTeX, 14 PostScript figures. Revised version with additions suggested by Phys. Rev. C

TRIUMF experiment E497 is a study of parity violation in pp scattering at an energy where the leading term in the analyzing power is expected to vanish, thus measuring a unique combination of weak-interaction flavour conserving terms. It is desired to reach a level of sensitivity of 2x10^-8 in both statistical and systematic errors. The leading systematic errors depend on transverse polarization components and, at least, the first moment of transverse polarization. A novel polarimeter that measures profiles of both transverse components of polarization as a function of position is described., 19 pages LaTeX, 10 PostScript figures. To appear in Nuclear Instruments and Methods in Physics Research, Section A

Parity violation in proton-proton elastic scattering provides a unique window on the hadronic weak interaction. At low and intermediate energies, the coupling constants of an effective meson exchange model provide an appropriate parametrization. Measurements at different beam energies permit the lowest partial wave amplitudes to be determined in a model independent framework. The TRIUMF cyclotron provides a unique opportunity to measure the 3P2−1D2 contribution to proton-proton parity violation at 221 MeV beam energy. This partial wave in turn isolates the weak ρ meson exchange contribution, which is only known to within a factor of 2 from theoretical estimates. An experiment underway for many years at TRIUMF completed data taking in 1999, and the analysis is now nearing completion. Preliminary results, based on half of the acquired data sample, are consistent with the meson exchange model prediction at this beam energy.

Holography has been used successfully in combination with conventional optics for the first time in a large cryogenic bubble chamber, the 15-Foot Bubble Chamber at Fermilab, during a physics run. The innovative system combined the reference beam with the object beam, illuminating a conical volume of $\sim 1.4$~m$^3$. Bubble tracks from neutrino interactions with a width of $\sim 120\;\mu$m have been recorded with good contrast. The ratio of intensities of the object light to the reference light striking the film is called the Beam Branching Ratio. We obtained in our experiment an exceedingly small minimum-observable ratio of $(0.54 \pm 0.21) \times 10^{-7}$. The technology has the potential for a wide range of applications.

An experiment (E497) is underway at TRIUMF to measure the angle-integrated, parity violating longitudinal analyzing power, A{sub z}, in proton-proton elastic scattering, to a precision of {plus_minus}0.2{times}10{sup {minus}7}. The experiment uses a 221 MeV longitudinally polarized proton beam incident on a 40 cm liquid hydrogen target. The beam energy is carefully chosen so that the contribution to A{sub z} from the J=0 parity mixed partial wave ({sup 1}S{sub 0}{minus}{sup 3}P{sub 0}) integrates to zero over the acceptance of the apparatus, leaving the experiment sensitive mainly ({gt}95{percent}) to A{sub z} arising from the {sup 3}P{sub 2}{minus}{sup 1}D{sub 2}, J=2 wave. To minimize sources of systematic error, the TRIUMF ion source and cyclotron parameters have been refined to the extent that helicity correlated beam changes are at an extremely low level, and specialized instrumentation on the E497 beamline is able to measure residual helicity correlated modulations to a precision consistent with the goals of the experiment. A data taking run in February-March, 1997 logged approximately 12{percent} of the desired data and produced a preliminary result, A{sub z}=(1.1{plus_minus}0.4{plus_minus}0.4){times}10{sup {minus}7}, where the error is statistical only. {copyright} {ital 1997 American Institute of Physics.}

Measurements of parity-violating longitudinal analyzing powers (normalized asymmetries) in polarized proton-proton scattering provide a unique window on the interplay between the weak and strong interactions between and within hadrons. Several new proton-proton parity violation experiments are presently either being performed or are being prepared for execution in the near future: at TRIUMF at 221 MeV and 450 MeV and at COSY (Kernforschungsanlage Juelich) at 230 MeV and near 1.3 GeV. These experiments are intended to provide stringent constraints on the set of six effective weak meson-nucleon coupling constants, which characterize the weak interaction between hadrons in the energy domain where meson exchange models provide an appropriate description. The 221 MeV is unique in that it selects a single transition amplitude (3P2-1D2) and consequently constrains the weak meson-nucleon coupling constant h_rho{pp}. The TRIUMF 221 MeV proton-proton parity violation experiment is described in some detail. A preliminary result for the longitudinal analyzing power is Az = (1.1 +/-0.4 +/-0.4) x 10^-7. Further proton-proton parity violation experiments are commented on. The anomaly at 6 GeV/c requires that a new multi-GeV proton-proton parity violation experiment be performed., Comment: 13 Pages LaTeX, 5 PostScript figures, uses espcrc1.sty. Invited talk at QULEN97, International Conference on Quark Lepton Nuclear Physics -- Nonperturbative QCD Hadron Physics & Electroweak Nuclear Processes --, Osaka, Japan May 20--23, 1997

Precision measurements of parity violation in proton-proton scattering impose very stringent requirements on the polarized beam quality. The contributions of random and spin-correlated beam modulations to the experimental accuracy are discussed. This analysis for the TRIUMF optically pumped polarized ion source and H− ion cyclotron with multiturn extraction is quite different from previous experiments at LAMPF, PSI and Bonn. The required beam quality is obtained by combining efforts at every stage: reduction of modulations at the source, minimization of transfer coefficients in the injection line and cyclotron, feedback systems for injected and accelerated beam stabilization, precision measurements of the beam energy, intensity and polarization profiles, and reduction of the sensitivities of the experimental apparatus to these modulations.

The angles at which the {ital n}-{ital p} elastic scattering neutron analyzing power {ital A}{sub 00{ital n}0} crosses zero were measured with precision at four TRIUMF energies below 300 MeV. The mean interaction energies are also measured with greater precision than in previous experiments. The results are {ital E}{sub {ital n}}=175.26{plus_minus}0.23 MeV, {theta}{sub {ital zx}}=98.48{degree}{plus_minus}0.28{degree}; {ital E}{sub {ital n}}=203.15{plus_minus}0.20 MeV, {theta}{sub {ital zx}}=91.31{degree}{plus_minus}0.18{degree}; {ital E}{sub {ital n}}=217.24{plus_minus}0.19 MeV, {theta}{sub {ital zx}}=87.64{degree}{plus_minus}0.18{degree}; and {ital E}{sub {ital n}}=261.00{plus_minus}0.16 MeV, {theta}{sub {ital zx}}=80.18{degree}{plus_minus}0.19{degree}. After correction for charge symmetry breaking effects, the energy where the {ital averaged} neutron-proton analyzing power crosses zero at {theta}{sub {ital zx}}=90{degree} is found to be {ital E}{sub {ital n}}=206.8{plus_minus}0.6 MeV. {copyright} {ital 1996 The American Physical Society.}

TRIUMF Experiment 369, a measurement of charge symmetry breaking in np elastic scattering at 350 MeV, has completed data taking. Scattering asymmetries were measured with a polarized (unpolarized) neutron beam incident on an unpolarized (polarized) frozen spin target. Coincident scattered neutrons and recoil protons were detected by a mirror symmetric detection system in the center‐of‐mass angle range from 50°–90°. A preliminary result for the difference of the zero‐crossing angles, where analyzing powers cross zero, is Δθcm =0.445°±0.054°(stat.)±0.051°(syst.) based on fits over the angle range 53.4°≤θcm≤86.9°. The difference of the analyzing powers ΔA≡An−Ap, where the subscripts denote polarized nucleons, was deduced with dA/dθcm=(−1.35±0.05)×10−2 deg−1 to be [60±7(stat.)±7(syst.)±2(syst.)] ×10−4.

TRIUMF experiment 369, a measurement of charge symmetry breaking in np elastic scattering at 350 MeV, has completed data taking. Scattering asymmetries were measured with a polarized (unpolarized) neutron beam incident on an unpolarized (polarized) frozen spin target. Coincident scattered neutrons and recoil protons were detected by a mirror symmetric detection system in the center of mass angle range from 50°–90°. A preliminary result for the difference of the zero‐crossing angles, where analyzing powers cross zero, is Δθcm=0.48°±0.08°(stat.)±0.08°(syst.) based on fits over the angle range 55.8°≤θcm≤85.4°. The difference of the analyzing powers ΔA≡An−Ap, where the subscripts denote polarized nucleons, was deduced with dA/dθcm=−1.47×10−2 deg−1 from phase shift analyses to be [71±12(stat.)±12(syst.)]×10−4. It is expected that when all data are analyzed a statistical accuracy of about 7×10−4 in ΔA will be achieved.

The TRIUMPF experiment 497 which will measure the (weak) parity violating component of the nucleon‐nucleon interaction with proton‐proton quasi‐elastic scattering at 223 MeV is described. The longitudinal analyzing power Az=(σ+−σ−)/(σ++σ−) where σ+ and σ− are the scattering cross sections for positive and negative beam helicity, respectively, with an expected precision of ±2×10−8. (AIP)

The zero point of the analyzing power for neutron‐proton scattering has been measured as a function of scattering angle for 4 incident neutron energies, 174.3, 202.4, 216.5, and 260.3 MeV. The accuracy is ±0.25°. (AIP)

A polarimeter capable of determining transverse component polarization profile of the 222 MeV proton beam both in horizontal (x) and vertical (y) directions with faster than 1 Hz scanning frequency has been developed and built as part of the preparations in the TRIUMF Experiment 497 measuring the flavour conserving hadronic weak interaction (parity violation measurement). The design features and test performance results are presented.

We measured the relative differential cross section and analyzing powers A SO, A NO and A LO for the reaction np→ppπ− at an incident neutron energy of 443 MeV. The geometry of our detector allowed us to sample almost all the available phase-space. We reconstructed the full kinematics of each event from the measured trajectories of at least two of the three final state particles. Cuts based on the vertex reconstruction and kinematic χ2 allowed us to remove most background, primarily nn→npπ− from the target walls and other materials. These cuts gave a signal-to-noise ratio of 22:1, but fewer than 3% of the total data survived the cuts. The resulting ~400,000 np→ppπ− were binned against p-p invariant mass and angles which are most suited to partial waves analysis. Comparisons are made to predictions of the model of Kloet and Lomon. These observables represent the first measurements of their kind at this energy and it is hoped that their determination will allow us to extract the role of isospin-0 amplitudes in the process of pion production.

From an exposure of the Fermilab 15-foot bubble chamber to the Tevatron quadrupole triplet neutrino beam, we have determined the ratio of neutral-current (NC) to charged-current (CC) interactions to be 0.288{plus minus}0.032 for events with visible hadron momentum above 10 GeV/{ital c}. The mean {nu}({bar {nu}}) event energy is 150 (110) GeV, which is higher than that for any previous beam. This result agrees with those from previous experiments at lower energies. The NC/CC ratio is derived for a combined sample of {nu} and {bar {nu}} events. A value of 0.274{plus minus}0.038 is obtained for the dominant {nu} component assuming {bar {nu}} NC/CC=0.39{plus minus}0.08. For events with visible hadron momentum above 25 GeV/{ital c}, where the neutral hadron contamination remaining in the NC sample is assumed to be negligible, the combined NC/CC is 0.323{plus minus}0.025 and the {ital K}{sup 0} production rates are 0.375{plus minus}0.064 per CC and 0.322{plus minus}0.073 per NC event. The corresponding {Lambda} rates are 0.161{plus minus}0.030 per CC and 0.113{plus minus}0.030 per NC event. The {ital K}{sup 0} and {Lambda} distributions of the fractional hadron energy variable {ital z} in NC events are consistent with those in CC events.

The validity of charge symmetry has long been of fundamental interest and much circumstantial evidence has accumulated over the years favoring charge symmetry breaking (CSB) on the order of a fraction of a percent. Although low energy nucleon-nucleon scattering studies have shown a slight inequality of the nn and pp scattering lengths[1], it has proved very difficult to remove experimental and theoretical uncertainties to isolate charge symmetry breaking interactions unequivocally. Evidence of CSB is present in π scattering from 3 H and 3 He and in π — d total and differential cross section measurements[2],[3],[4],[5]. The π — d results have been interpreted in terms of mass splittings in the Δ system. Differences in the binding energies of mirror nuclei (the Nolen-Schiffer effect) hint at the presence of charge symmetry breaking terms in the interaction but, again, the isolation and removal of electromagnetic (EM) effects has proved difficult[6],[7].

The department is the basic operating unit in academe. It is where faculty function and the unit with which students, alumni, and clientele groups identify. Characteristics and responsibilities of effective departmental administrative officers, as well as college administrators’ expectations of and working relationships with them, are discussed.

The discovery of the silvered leaf monkey, Presbytis cristata, as a suitable experimental host for the human filarial parasite, Wuchereria bancrofti, opened the door for major advances in our understanding of the disease caused by this parasite. To study the pathogenesis of bancroftian filariasis in this model, 15 adult P. cristata which had been experimentally infected with 250 infective third-stage larvae of the parasite were examined. After inoculation with larvae, the monkeys were maintained under study for periods of 2 to 3 years, at which time all had achieved patent infections. At necropsy, Wuchereria-induced macroscopic lesions were not detected in experimentally infected monkeys. Microscopic findings included nematodiasis, microfilariasis, lymphadenitis, lymphangiectasis, perilymphangitis, splenitis, orchitis, periorchitis, epididymitis and funiculitis. Sections of normal adult worms were most often found in lymphatic vessels near lymph nodes, or in the lymphatics of the male genital system. These worms caused microfiliariasis in some regional lymph nodes. Inflammatory responses to filariae were most prominent in proximity to degenerated and dead worms, whereas intact, normal appearing adult worms elicited only minimal cellular response.

The possibility of gingival fluid being a source of plaque fluoride has been investigated in dogs anaesthetised for veterinary examination and dental treatment. The radionuclide18F was injected intravenously and the tracer was detected in gingival fluid within 5 min of injection. The concentration of tracer in plaque was similar to that in plasma by 25 min, even in the absence of saliva, but gingival fluid and plasma had substantially the same concentration at all times. After 25 min the concentration in gingival fluid and plaque were also observed to be the same. The results suggest that gingival fluid is one source of plaque fluoride but calculation shows that it is unlikely to account for the whole.