Near-Infrared Kinetic Spectroscopy of the HO_2 and C_2H_5O_2 Self-Reactions and Cross Reactions

The self-reactions and cross reactions of the peroxy radicals HO_2 and C_2H_5O_2 and HO_2 were monitored using simultaneous independent spectroscopic probes to observe each radical species. Wavelength modulation (WM) near-infrared (NIR) spectroscopy was used to detect HO_2, and UV absorption monitored HO_2 and C_2H_5O_2. The temperature dependences of these reactions were investigated over a range of interest to tropospheric chemistry, 221−296 K. The Arrhenius expression determined for the cross reaction, k_2(T) = (6.01^(+1.95)_(−1.47)) × 10^(−13) exp((638 ± 73)/T) cm^3 molecules^(−1) s^(−1) is in agreement with other work from the literature. The measurements of the HO_2 self-reaction agreed with previous work from this lab and were not further refined.(1) The C_2H_5O_2 self-reaction is complicated by secondary production of HO_2. This experiment performed the first direct measurement of the self-reaction rate constant, as well as the branching fraction to the radical channel, in part by measurement of the secondary HO_2. The Arrhenius expression for the self-reaction rate constant is k_3(T) = (1.29^(+0.34)_(−0.27)) × 10^(−13)exp((−23 ± 61)/T) cm^3 molecules^(−1) s^(−1), and the branching fraction value is α = 0.28 ± 0.06, independent of temperature. These values are in disagreement with previous measurements based on end product studies of the branching fraction. The results suggest that better characterization of the products from RO_2 self-reactions are required

Designing tools to predict and mitigate impacts on water quality following the Australian 2019/2020 wildfires: Insights from Sydney's largest water supply catchment

The 2019/20 Australian bushfires (or wildfires) burned the largest forested area in Australia's recorded history, with major socio‐economic and environmental consequences. Among the largest fires was the 280,000 ha Green Wattle Creek Fire which burned large forested areas of the Warragamba catchment. This protected catchment provides critical ecosystem services for Lake Burragorang, one of Australia's largest urban supply reservoirs delivering ~85 % of the water used in Greater Sydney. WaterNSW is the utility responsible for managing water quality in Lake Burragorang. Its postfire risk assessment, carried out in collaboration with researchers in Australia, the UK and USA, involved i) identifying pyrogenic contaminants in ash and soil; ii) quantifying ash loads and contaminant concentrations across the burned area; and iii) estimating the probability and quantity of soil, ash and associated contaminants entrainment for different rainfall scenarios. The work included refining the capabilities of the new WEPPcloud‐WATAR‐AU model (Water Erosion Prediction Project cloud‐Wildfire Ash Transport And Risk‐Australia) for predicting sediment, ash and contaminants transport, aided by outcomes from previous collaborative post‐fire research in the catchment. Approximately two weeks after the Green Wattle Creek Fire was contained, an extreme rainfall event (~276 mm in 72 h), caused extensive ash and sediment delivery into the reservoir. The risk assessment informed on‐ground monitoring and operational mitigation measures (deployment of debris‐catching booms and adjustment of the water supply system configuration), ensuring the continuity of safe water supply to Sydney. WEPPcloud‐WATAR‐AU outputs can prioritize recovery interventions for managing water quality risks by quantifying contaminants on the hillslopes, anticipating water contamination risk, and identifying areas with high susceptibility to ash and sediment transport. This collaborative interaction among scientists and water managers, aimed also at refining model capabilities and outputs to meet managers’ needs, exemplifies the successful outcomes that can be achieved at the interface of industry and science

Measurement of B(Ds+ -->ell+ nu) and the Decay Constant fDs From 600/pb of e+e- Annihilation Data Near 4170 MeV

We examine e+e- --> Ds^-D_s^{*+} and Ds^{*-}Ds^{+} interactions at 4170 MeV using the CLEO-c detector in order to measure the decay constant fDs with good precision. Previously our measurements were substantially higher than the most precise lattice based QCD calculation of (241 +/- 3) MeV. Here we use the D_s^+ --> ell^+ nu channel, where the ell^+ designates either a mu^+ or a tau^+, when the tau^+ --> pi^+ anti-nu. Analyzing both modes independently, we determine B(D_s^+ --> mu^+ nu)= 0.565 +/- 0.045 +/- 0.017)%, and B(D_s^+ --> mu^+ nu)= (6.42 +/- 0.81 +/- 0.18)%. We also analyze them simultaneously to find an effective value of B^{eff}(D_s^+ --> mu^+ nu)= (0.591 +/- 0.037 +/- 0.018)% and fDs=(263.3 +/- 8.2 +/- 3.9) MeV. Combining with the CLEO-c value determined independently using D_s^+ --> tau^+ nu, tau^+ --> e^+ nu anti-nu decays, we extract fDs=(259.5 +/- 6.6 +/- 3.1) MeV. Combining with our previous determination of B(D^+ --> mu^+ nu), we extract the ratio fDs/fD+=1.26 +/- 0.06 +/- 0.02. No evidence is found for a CP asymmetry between Gamma(D_s^+ --> mu^+\nu) and \Gamma(D_s^- --> mu^- nu); specifically the fractional difference in rates is measured to be (4.8 +/- 6.1)%. Finally, we find B(D_s^+ --> e^+ nu) < 1.2x10^{-4} at 90% confidence level.Comment: 26 pages, 16 figure

Achieving sustainable construction within Private Finance Initiative (PFI) road projects in the UK

The construction industry is facing the challenge of increasing demands of its sustainability performance. The construction and maintenance of the built environment has substantial impact on the sustainability of the environment. Whist, public sector clients are increasingly asking for a sustainable approach in their specification and procurement decisions, sustainability is still seen as a novel concept within the construction industry in many parts of the world without a settled definition. The premise of this study is that the interaction between road projects realized by the private finance initiative and their delivery in the UK improve sustainability. The paper, based on case study research, explains the sustainability implementation in a PFI road project and demonstrates that the PFI mechanism facilitates sustainable implementation to a far greater extent than is achievable using traditional procurement methods

Pilot Study to Evaluate the Association Between the Length of the Luteal Phase and Estrous Activity Detected by Automated Activity Monitoring in Dairy Cows

The ability of automated activity monitoring (AAM) systems to detect estrus is influenced by multiple variables. The luteal phase (LP) preceding estrus has been shown to be important for hormones release, and behavior during estrus in ruminants, but its impact on activity as measured by AAM systems has not been studied. The objective of this study was to investigate the impact of the length of the preceding LP on the intensity and duration of estrus as measured by AAM, and on the expression of estrogen receptor alpha (ERα) in the endometrium. A total of 60 cows between 46 and 53 days in milk were assigned to either a normal or a short length LP. Length of the LP was insured by the use of hormonal synchronization programs. Cows in both treatments were matched on parity, milk production, body condition score (BCS), and lameness score (assessed at enrolment). Expression of ERα receptors in the endometrium were evaluated by nuclear staining by immunohistochemistry of biopsies. Estrus was defined as the day on which the AAM system detected estrus. Cows that were not synchronized by the protocol or that were not detected in estrus by the AAM systems were excluded, which left 21 and 11 cows for analyses in the normal and short length LP, respectively. Peak activity index of estrus, duration of estrus, and expression of ERα were outcomes for multivariable linear regression models. Cows with short length LP tended to have lower peak activity at estrus, but there was no significant effect of treatment when BCS was accounted for. Cows with BCS ≤ 2.5 had less intense and shorter estrus than cows with BCS ≥ 2.75. There was no association between the length of the LP and the expression of ERα in the endometrium

Higher-order multipole amplitudes in charmonium radiative transitions

Using 24 million $\psi' \equiv \psi(2S)$ decays in CLEO-c, we have searched for higher multipole admixtures in electric-dipole-dominated radiative transitions in charmonia. We find good agreement between our data and theoretical predictions for magnetic quadrupole (M2) amplitudes in the transitions $\psi' \to \gamma \chi_{c1,2}$ and $\chi_{c1,2} \to \gamma J/\psi$, in striking contrast to some previous measurements. Let $b_2^J$ and $a_2^J$ denote the normalized M2 amplitudes in the respective aforementioned decays, where the superscript $J$ refers to the angular momentum of the $\chi_{cJ}$. By performing unbinned maximum likelihood fits to full five-parameter angular distributions, we determine the ratios $a_2^{J=1}/a_2^{J=2} = 0.67^{+0.19}_{-0.13}$ and $a_2^{J=1}/b_2^{J=1} = -2.27^{+0.57}_{-0.99}$, where the theoretical predictions are independent of the charmed quark magnetic moment and are $a_2^{J=1}/a_2^{J=2} = 0.676 \pm 0.071$ and $a_2^{J=1}/b_2^{J=1} = -2.27 \pm 0.16$.Comment: 32 pages, 7 figures, acceptance updat

Search for D0 to p e- and D0 to pbar e+

Using data recorded by CLEO-c detector at CESR, we search for simultaneous baryon and lepton number violating decays of the D^0 meson, specifically, D^0 --> p-bar e^+, D^0-bar --> p-bar e^+, D^0 --> p e^- and D^0-bar --> p e^-. We set the following branching fraction upper limits: D^0 --> p-bar e^+ (D^0-bar --> p-bar e^+) p e^- (D^0-bar --> p e^-) < 1.2 * 10^{-5}, both at 90% confidence level.Comment: 10 pages, available through http://www.lns.cornell.edu/public/CLNS/, submitted to PRD. Comments: changed abstract, added reference for section 1, vertical axis in Fig.5 changed (starts from 1.5 rather than 2.0), fixed typo

Dalitz Plot Analysis of Ds to K+K-pi+

We perform a Dalitz plot analysis of the decay Ds to K+K-pi+ with the CLEO-c data set of 586/pb of e+e- collisions accumulated at sqrt(s) = 4.17 GeV. This corresponds to about 0.57 million D_s+D_s(*)- pairs from which we select 14400 candidates with a background of roughly 15%. In contrast to previous measurements we find good agreement with our data only by including an additional f_0(1370)pi+ contribution. We measure the magnitude, phase, and fit fraction of K*(892) K+, phi(1020)pi+, K0*(1430)K+, f_0(980)pi+, f_0(1710)pi+, and f_0(1370)pi+ contributions and limit the possible contributions of other KK and Kpi resonances that could appear in this decay.Comment: 21 Pages,available through http://www.lns.cornell.edu/public/CLNS/, submitted to PR

Charmonium decays to gamma pi0, gamma eta, and gamma eta'

Using data acquired with the CLEO-c detector at the CESR e+e- collider, we measure branching fractions for J/psi, psi(2S), and psi(3770) decays to gamma pi0, gamma eta, and gamma eta'. Defining R_n = B[ psi(nS)-->gamma eta ]/B[ psi(nS)-->gamma eta' ], we obtain R_1 = (21.1 +- 0.9)% and, unexpectedly, an order of magnitude smaller limit, R_2 < 1.8% at 90% C.L. We also use J/psi-->gamma eta' events to determine branching fractions of improved precision for the five most copious eta' decay modes.Comment: 14 pages, available through http://www.lns.cornell.edu/public/CLNS/, published in Physical Review