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A significant increase in treatment pace and scale is needed to restore dry western US forest resilience owing to increasingly frequent and severe wildfire and drought. We propose a pyrosilviculture approach to directly increase large-scale fire use and modify current thinning treatments to optimize future fire incorporation. Recommendations include leveraging wildfire’s “treatment” in areas burned at low and moderate severity with subsequent pyrosilviculture management, identifying managed wildfire zones, and facilitating and financing prescribed fire with “anchor,” “ecosystem asset,” and “revenue” focused thinning treatments. Pyrosilviculture would also expand prescribed-burn and managed-wildfire objectives to include reducing stand density, increasing forest heterogeneity, and selecting for tree species and phenotypes better adapted to changing climate and disturbance regimes. The potential benefits and limitations of this approach are discussed. Fire is inevitable in dry western US forests and pyrosilviculture focuses on proactively shifting more of that fire into managed large-scale burns needed to restore ecosystem resilience.

The recent availability of reliable and relatively low-cost GaN based semi-conductor laser diode sources emitting at 404 nm has opened many new areas for fluorescence based measurements. This article characterizes the fluorescence behavior of commercial liquid-phase gasoline samples using such excitation sources. Comparison is drawn with the emission when excited using broad-band sources at shorter wavelengths (340 nm). Here, 404 nm is shown to selectively excite the larger CxHypolycyclic aromatic hydrocarbons (PAH) commonly found as minor constituents of gasoline, mainly for (x, y) ≥ (14, 10). Both Stokes and anti-Stokes shifted emission was observed in all the gasoline tested and in some PAH samples. The fluorescence is usually superimposed on Raman scattered laser light, arising from vibrations within the basic benzene structures. The fluorescence features of the gasoline samples tested were found to be broadly similar, but, because of its distinctive spectroscopic features, the fluorescence arising from benzo(a)pyrene was found to be one of the main variants. More generally, principal component analysis of the spectra was able to highlight differences between both the sample provenance and the fuel variety.

We report an All-Opto-Electronic tomography system that is sensitive to hydrocarbon vapour distribution, or liquid spray distribution, with temporal resolution of over 3000 frames per second. A tomography system comprising 32 channels has been built and tested. For chemical sensitivity to saturated hydrocarbons, we exploit the principle of Near Infra-Red (NIR) absorption at 1700 nm relative to a reference wavelength, using laser diode sources whose technology is based on that of the communications industry. Images are obtained from a laboratory set-up incorporating both gaseous injection and a liquid Gasoline Direct Injection (GDI) system. The performance of a prototype system on a running GDI engine is reported. The difficulty in performing concentration measurements of the gaseous fuel within the liquid spray region is shown, and means to improve this performance are discussed. However, it has been found possible to image the liquid spray cone using attenuation of the reference beam. These images correlate well with other techniques [1].

Despite concern over high pregnancy rates and levels of risk for sexually transmittedinfections, adolescent fertility rates in the Dominican Republic have not changed substantially since the early 1980's, and actually increased during the early to mid 1990s. The present study was undertaken to assess the factors contributing to the recent rise in fertility among Dominican adolescents. The findings suggest that although contraceptive use among adolescents and young adults has increased, this has been more than offset by ominous trends on other determinants of fertility. Among these are declines in mean age at first sex and first marriage/union without a commensurate decline in mean age at first contraceptive use, and stubbornly high discontinuation rates for oral contraceptives andcondoms. There is also some evidence that rates of induced abortion among adolescents may have increased, without which adolescent fertility rates would have been even higher. Demand for children among Dominican adolescents remains strong, suggesting that efforts to reduce the current high prevalence of risky sexual behaviors need to influence social norms in order to be successful.

Six cases with a clinical corticobasal syndrome (progressive asymmetric apraxia and parkinsonism unresponsive to levodopa) and tau pathology were selected from 97 brain donors with parkinsonism. Postmortem volumetric measures of regional brain atrophy (compared with age/sex‐matched controls) were correlated with clinical features and the degree of underlying cortical and subcortical histopathology. At death, no significant asymmetry of pathology was detected. All cases had prominent bilateral atrophy of the precentral gyrus (reduced by 22–54%) with other cortical regions variably affected. Subcortical atrophy was less severe and variable. Two cases demonstrated widespread atrophy of basal ganglia structures (44–60% atrophy of the internal globus pallidus) and substantial subcortical pathology consistent with a diagnosis of progressive supranuclear palsy (PSP). The remaining four cases had typical pathology of corticobasal degeneration. In all cases, neuronal loss and gliosis corresponded with subcortical atrophy, while the density of cortical swollen neurons correlated with cortical volume loss. Atrophy of the internal globus pallidus was associated with postural instability, while widespread basal ganglia histopathology was found in cases with gaze palsy. This study confirms the involvement of the precentral gyrus in the corticobasal syndrome and highlights the variable underlying pathology in these patients. © 2001 Movement Disorder Society

The spatial distribution of chemical species can be a critical determinant of the performance of chemical reactors. One such reactor is the combustion chamber of the Internal Combustion engine. This paper presents a design for the measurement of hydrocarbon concentration distribution within a running engine using near infra-red absorption tomography. The fundamentals of the technique, and design parameters for the equipment are discussed. By utilising micro-optic components, a minimally invasive system is feasible and by utilising advanced laser/photodetector combinations, good temporal performance is anticipated.

This article presents research findings on the question of whether the monetization of non-emergency food aid has adversely influenced national family planning program efforts in Honduras. Women receiving food aid in the form of cash coupons are compared in the study with women receiving food rations and a third group of women with similar characteristics who were not food aid recipients on three types of outcomes: recent fertility, fertility preferences, and contraceptive use. The health facilities where study subjects received health/family planning services and food aid benefits were also compared to assess possible adverse cross-program effects on family planning service delivery. A ‘sample selection’ model was used in the analysis to control for unobserved differences between comparison groups. No compelling evidence for adverse demand- or supply-side effects of monetized food aid on family planning efforts was observed. The most striking study finding was the extremely high level of unmet need for family planning.

The fraction of the total available energy carried by photons and the fraction carried by neutral particles of all types ine+e- multihadron final states have been measured at three centre-of-mass energies between 12 and 35 GeV. These fractions are approximately 27% and 37% with no strong dependence on centre-of-mass energy and the event topology. The neutrino energy fraction is estimated to be less than 10% at the 95% confidence level.

Measurements are reported of inclusivef2(1270) andf0(975) production in ?p, p±p andK±p collisions at photon beam energies of 65 to 175 GeV and hadron beam energies of 80 and 140 GeV. Thef2 andf0 mesons were found at masses of 1.250 GeV and 0.961 GeV respectively. Inclusivef2 production at lowxF was found to have a similarpT dependence for each beam type, whereas an additional pion-exchange contribution was found for production by pions at highxF. Cross sections are compared with those for ?0 production and give no indication of a non-q component in eitherf-meson state.

Photo- and hadroproduction data in the beam energy range 65–175 GeV have been studied with a view to isolating higher-twist processes in photoproduction from other point-like and hadron-like contributions. With selection of charged tracks havingpT>2 GeV/c and 0.28F<0.84 indications of a higher twist contribution have been found at a level that is consistent with QCD expectations.

The charged particle asymmetry, (n+-n-)/(n++n-), in inclusive photoproduction of charged particles on protons has been studied as a function ofxF andpT in the rangesxF>0 and 0T<2 GeV/c and for photon energies in the range 65?<175 GeV. The asymmetry is found to be positive and decreasing withE?. Asymmetries of p's and K's in the final state have been obtained separately. Data from a carbon target show a significantly lower asymmetry. These results have been compared with a parton, recombination model which provides a qualitative explanation for the asymmetry and itsxF andE? dependences. The model also gives a qualitative understanding of the lower asymmetry seen with the nuclear target.

Abstract: Energy-flow distributions for charged hadrons from interactions of photons, pions and kaons on hydrogen are presented as functions of Σp T2 in the event plane. Data cover the range 0.0<Σp T in2 <10.0(GeV/c)2 and 0.0 F <1.0 for beam momenta from 65 to 170 GeV/c. The comparisons between photon-and hadron-induced data show an excess of events with larger Σp T in2 for the photon-induced data. Using the hadron-induced data to parameterise the hadronic behaviour of the photon, the differences between cross sections are used to measure the contribution of the point-like photon interactions. Quantitative calculations of the point-like photon interactions using the Lund Monte-Carlo program LUCIFER, based on QCD, are in agreement with the data.

A search has been made for the chargino, the supersymmetric partner of theW± (or the partner of the charged Higgs bosons), ine+e- annihilation at PETRA using the JADE detector. The chargino decay modes investigated are and (with subsequent gluino decay ). No evidence for such events has been observed. The 95% C.L. lower limit for the chargino mass is typically 22.5 GeV, depending only slightly on the masses of other supersymmetric particles. If the chargino is stable, the lower mass limit is 21.1 GeV (95% C.L.).

The production of collinear muon pairs has been studied using the JADE detector at thee+e− storage ring at PETRA. Results for the total cross section and the angular distribution were obtained at centre of mass (cm) energies ranging from 12 to 46 GeV. The data correspond to an integrated luminosity offLdt>90 pb−1, of which 71.2 pb−1 were taken at =34.4 GeV and 17 pb−1 at =42.4 GeV. The results are compared to electroweak theories, in particular the “Standard Model”.

The mean charged multiplicity as well as its distribution has been measured as a function of c.m. energy in the reactione+e-?hadrons. Fragmentation models are compared with the data. After applying radiative corrections the mean charged multiplicity is measured to be 8.4±0.3±0.6 at 12 GeV, 13.1±0.3±0.6 at 30 GeV and 13.6±0.3±0.6 at 35 GeV. The ratio of mean charged multiplicity to the dispersion (ch>/Dch) is almost constant in the energy range studied, indicating KNO scaling of the charged multiplicity. The inclusive differential cross sections(ds/dxp) shows scaling violation in the highxp region (xp>0.15). The absolute value of the scaling violation is consistent with the result of 2nd order QCD calculations. The production of neutral kaons has been investigated by identifying the decayKS0?p+p-. The production probability for a strange quark relative to that of au ord quark in the fragmentation, ?s, has been determined to be 0.27±0.03±0.05 averaged over c.m. energies from 12 to 35 GeV. Momentum spectra for neutral kaons are presented and are compared with model predictions.

Measurements are reported of inclusive production of η-mesons in the beam fragmentation region in γp, πp andKp collisions. Results include a small but significant departure from VMD, and a pronounced rise in theη/π0 ratio with increasingpT.

The inclusive production of ρ0 mesons was measured in γp andh±p collisions at beam energies of 65 GeV≦Eγ≦175 GeV andEh=80, 140 GeV, respectively, whereh is π orK. Cross sections were determined for all beams and energies as functions ofxF (−0.1≦xF≦1.0),pT (0≦pT≦3.5 GeV/c) and the polar decay angle of the ρ0 by fitting the ρ0 signal in π+π- mass distributions. The ρ0 line shape is found to be distorted from a pure Breit-Wigner distribution throughout most of thexF−pT plane for both photon and hadron beams and a simple explanation is suggested. Throughout the paper emphasis is put on the comparison of photon and hadron beam data. The comparison of cross sections of γp andhp data provides a measure of the Vector Meson Dominance factor throughout thexF−pT range of the ρ0. The ρ0 production at lowpT can be described for both photon and hadron beams by a triple regge model at largexF. Similarly central production is well described by the quark-antiquark fusion model. At largepT there is an excess of ρ0 photoproduction which is consistent with the expected onset of pointlike photon interactions.

Inclusive production of ϕ,K*0, and mesons has been measured in γp, π±p andK± p collisions at beam energies of 65 GeVγ<175 GeV andEπ/K =80 and 140 GeV. Cross sections have been determined over the range 0F<1.0 and 0T<1.8 GeV/c. Emphasis is put on the comparison of cross sections for different projectiles as a function ofxF so as to study the effects of common quarks between the beam particle and the detected ϕ,K*0 or . The data are compared with a parton fusion model. Many features of the data are well explained. In detail the strange quark appears to carry a large fraction of the kaon momentum and the contribution of the valence quarks from the proton is small.

Drug use may be either prescribed or proscribed depending on the drug and/or the nature of procurement. Marijuana and other drugs of those not in power are proscribed. Although males smoke and sell marijuana somewhat more than females there was no strong association between any of the background variables and drug use variables, supporting the position that drug use has become a positive value within the student culture. The data showed that involvement in the selling of marijuana and other drugs is related to the illegal aspects of procurement and distribution of marijuana, a network which can only be broken by legalization.An investigation of patterns of drug use among undergraduates at a New England university shows that marijuana use has become a normal part of student life even among men and women, athletes, and good students. Furthermore, frequent use of marijuana is strongly associated with selling of marijuana, use of other illicit drugs and selling of those drugs, consistent with the hypothesis that the need to go through illegal channels to obtain marijuana leads to a progressive involvement with the drug subculture.

The location and number of brain stem serotonin-synthesizing neurons were analyzed in 11 patients with Alzheimer's disease (AD) and 5 agematched controls using immunohistochemical techniques. In addition, the number of neuritic plaques and neurofibrillary tangles in the cortex and brain stem raphe was evaluated, as was the number of Nissl-stained raphe neurons. AD patients could be classified into two groups based on their raphe pathology; patients with such pathology (AD+) and those without (AD-). The number of large raphe neurons correlated significantly with the number of serotonin-synthesizing neurons in control material, indicating that all large neurons were serotonergic. This relationship was not apparent in AD+ patients, in whom the number of serotonin-synthesizing neurons correlated with the number of neurofibrillary tangles in the raphe of these patients. This indicates that in AD+ patients the serotonin-synthesizing neurons were selectively affected. There was no correlation between raphe and cortical pathology or raphe pathology and patient sex, age, mini-mental score or depression score, even when such scores were weighted for the interval between testing and death. There was a trend for the raphe pathology to correlate with the age of onset and duration of dementia and the Blessed dementia score in AD+ patients. Most AD+ patients with severe raphe lesions had clinical dementia only, while AD- patients had additional clinical features. The raphe lesions were more dramatic in AD+ patients with a rapid progression of symptoms.

Patients with Type 1 diabetes mellitus have an increased risk of ischaemic heart disease (IHD). When diabetes is complicated by nephropathy this risk is further increased and asymptomatic IHD is common. New techniques for non‐invasive cardiac evaluation are now available and one of these, Dobutamine Stress Echocardiography (DSE), was studied in subjects with Type 1 DM and nephropathy who had no evidence of IHD. DSE was performed on 18 subjects (13 male, 5 female; mean age 37.8 ± 3.4 years), diabetes duration 23.7 ± 1.2 years and nephropathy diagnosed for 10.9 ± 1.3 years. There were 7 (38 %) positive scans—suggesting asymptomatic IHD; 16.7 % of subjects studied had a significant arrhythmia. Coronary angiography was performed in 6 of the 7 subjects with positive DSEs and was positive in only 2. These results suggest that DSE has a high rate of false positive results in Type 1 DM patients suffering from nephropathy and may limit its usefulness in these subjects. © 1998 John Wiley & Sons, Ltd.

Objective: The objective of this study was to correlate histologic changes in hibernating myocardium with dobutamine stress echocardiography (DSE). Methods: Patients (n = 8) with anterior regional wall motion abnormalities in the seven echocardiographic segments representing the territory supplied by a significantly stenosed left anterior descending coronary artery had preoperative DSE performed (yielding 56 segments for analysis). Two transmural biopsy specimens were taken from the anterior wall of the left ventricle during coronary artery bypass grafting. Results: Morphometric histologic analysis of biopsy specimens showed significantly less fibrosis in segments demonstrating inotropic reserve (p < 0.05) and significantly less fibrosis in segments demonstrating improvement in wall motion on echocardiography 3 months after revascularization (p < 0.05). DSE had a sensitivity of 100% and a specificity of 62% for detection of hibernating myocardial segments. Percent fibrosis was inversely correlated with percent nucleated cells (r = 0.66, p < 0.01) and directly correlated with cytoplasmic clearance (r = 0.76, p < 0.01). Conclusion: Inotropic response during DSE correlates with histologic evidence of hibernating myocardium. (Am Heart J 1998;135:952-59.)

ObjectivesTo compare HLA distribution in familial and non-familial dilated cardiomyopathy, because a serum marker that could identify families at risk of developing dilated cardiomyopathy should be of use in screening for the disease.Patients100 patients with dilated cardiomyopathy.Methods200 first degree relatives from 56 of the proband families were screened for dilated cardiomyopathy by echocardiography. The HLA profile of the patients with dilated cardiomyopathy, as well as of the familial and non-familial subgroups, was compared with that of 9000 normal controls.ResultsThe familial prevalence of dilated cardiomyopathy in this patient group was "definite" in 14 of 56 (25%) and "possible" in 25 of 56 (45%). The HLA-DR4 frequency in the 100 patients with dilated cardiomyopathy was similar to that in the 9000 controls (39% v 32%). However, the DR4 subtype was significantly more common in the 25 probands with a familial tendency to dilated cardiomyopathy than in the 31 probands with non-familial dilated cardiomyopathy (68% v 32%; P &lt; 0·05).ConclusionsThe present finding supports an HLA linked predisposition to familial dilated cardiomyopathy. The HLA type DR4 was significantly more common in familial than in non-familial cases. The DR4 halotype was associated with two thirds of the families at risk for dilated cardiomyopathy.

We have studied the distribution of particles within and between jets of 3-jet final states produced in the reactione+e-?hadrons at c.m. energies of 22 GeV and 29–36.4 GeV. The lowest energy jet shows distributions of transverse momenta, particle flow, and energy flow which differ significantly from those of the other two jets and from jets of 2-jet events atEcm=14 GeV. First order QCD calculations with subsequent fragmentation of quarks and gluons into hadrons indicate that the lowest energy jet has the largest probability of originating from a gluon. To reproduce the observed differences in an independent parton fragmentation model, the secondary quarks of a gluon jet have to have higher transverse momenta and lower parallel momenta than those of a quark jet. The particle densities between the jets as well as the correlation of transverse and longitudinal momenta of the particles within the jets favour models with fragmentation along the colour axes.

Measurements are reported of inclusive production of π0-mesons in the beam fragmentation region in γp, πp andKp collisions. Results include the ratio of π0 production inKp and πp collisions, showing reduced production from fragmentation of theK-meson, and the ratio of π0 production in photon and hadron collisions which shows agreement with modified Vector Meson Dominance at lowPT, and departures at higherPT signalling the onset of direct photon reactions. The pattern of departure from Feynman scaling at highPT points to a contribution of hard parton-parton collisions in both γp and πp collisions.

A search has been made for new particles with chargeQ=2/3, 1, 4/3, 5/3 produced ine+e−-reactions at PETRA. The energy range wasEcm=27–35 GeV. No such particles were found. Upper limits for the cross-section depending on the assumed mass and production spectrum are given. ForQ=2/3 quarks with mass less than 12 GeV/c2, upper limits (90% C.L.) are obtained both for inclusive and exclusive production. For the lifetime of theB-meson (mB=5GeV/c2) an upper limit τ≦2×10−9s is obtained.

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy, , the 1 δ limits 0.122 ϑw<0.38 are obtained for the weak mixing angle. The higher order (α3) QED processese+e−→e+e−γ ande+e−→γγγ are also studied and are found to agree with the α3 QED predictions. A search for excited electrons is carried out by investigating the (e±γ) invariant mass distribution in the reactione+e−→e+e−γ.

Single charged-particle inclusive cross sections for photon, pion and kaon beams on hydrogen at the CERN-SPS are presented as functions ofpTandxF. Data cover the range 0.01.6 GeV/c for the photon-induced data. Using the hadron-induced data to estimate the hadronic behaviour of the photon, the difference distributions and ratios of cross sections are a measure of the contribution of the point-like photon interactions. The data are compared with QCD calculations and show broadly similar features.

We have determined the lifetime ofB-hadrons produced ine+e- annihilation into multihadronic final states, by measuring the impact parameter of the track with respect to the centre of the interaction region. Two different analyses of the data were performed and gave compatible results. The lifetime is tB=1.8-0.4+0.5±0.4 ps.

Energy-energy-correlations (EEC) have been measured with the JADE detector at c.m. energies of 14 GeV, 22 GeV and in the region 29 GeVcm<36 GeV. Corrected results are presented of EEC and their asymmetry, which can be directly compared to theoretical predictions. At 〈Ecm〉=34 GeV a comparison with second order QCD predictions yields good agreement for the string model fragmentation resulting in a value of the strong coupling constant αs=0.165±0.01 (stat.). The independent fragmentation models, which yield values of αs between 0.10 and 0.15 depending on the treatment of energy and momentum conservation and of the gluon splitting, do not provide a satisfactory description of the data over the full angular range.

We observe production of a Ξ*(2370) in the reactions K−p→[YK¯π]K, [YK¯π]Kπ and [ΩK] (K or Kπ) at 8.25 GeV/cin a high statistics bubble chamber experiment. The mass and width are determined to be 2373 ± 8 MeV and 80 ± 25 MeV, respectively. The I= 1/2 assignment is strongly favoured.

1. Distribution and excretion of radiophosphorus labelled hexafluophosphate ion has been investigated in the rat. 2. The concentration of PF6in whole blood and plasma reached a maximum at 15 minutes, fell precipitously, and none was found 18 hours after its injection. 3. Evidence is presented that PF6is not hydrolyzed by the rat. 4. Injected PF6is rapidly and quantitatively excreted in the urine.