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1. Reactivity of gold and copper acetylide with a secondary borane

   https://doi.org/10.1039/D5CC06957B  

   Thornton, Ragene A; French, Kirk; Shuford, Kevin; Martin, Caleb D (January 2026, Chemical Communications)

   Bis(1-methyl-ortho-carboranyl)borane reacts with PPh₃Au acetylide to give an η²-1-borataallene Au complex while the Cu acetylide furnishes a CuPPh₃⁺alkynylborate complex with a hydride bridging boron to copper. 

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2. Characterizing and understanding the photovoltage in n-Si/Au light-addressable electrochemical sensors

   https://doi.org/10.1039/d4an00768a  

   Hussain, Armeen; Mancini, Kayla; Khatib, Yousef; O'Neil, Glen D (July 2024, The Analyst)

   The photovoltage (V_oc) of n-Si/Au photoelectrodes varies with the solution potential (E⁰) whenE⁰falls between the valence and conduction band edges of the semiconductor but is constant whenE⁰is more positive than the valence band edge. 

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3. Search for the double-charmonium state with ηcJ/ψ at Belle

   https://doi.org/10.1007/JHEP08(2023)121  

   Yin, J H; Li, Y B; Won, E; Adachi, I; Aihara, H; Al_Said, S; Asner, D M; Aushev, T; Ayad, R; Babu, V; et al (August 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> We measure the cross section ofe⁺e⁻→η_cJ/ψat the Υ(nS)(n= 1–5) on-resonance and 10.52 GeV off-resonance energy points using the full data sample collected by the Belle detector with an integrated luminosity of 955 fb⁻¹. We also search for double charmonium production ine⁺e⁻→η_cJ/ψvia initial state radiation near theη_cJ/ψthreshold. No evident signal of the double charmonium state is found, but evidence for thee⁺e⁻→ η_cJ/ψprocess is found with a statistical significance greater than 3.3σnear theη_cJ/ψthreshold. The average cross section near the threshold is measured and upper limits of cross sections are set for other regions. 

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4. Determination of Outer Radiation Belt MeV Electron Energization Rates and Delayed Response Times to Solar Wind Driving During Geomagnetic Storms

   https://doi.org/10.1029/2023JA032115  

   Srinivas, P; Spencer, E (July 2024, Journal of Geophysical Research: Space Physics)

   Abstract Radiation Belt Storm Probes (RBSP) data show that seed electrons generated by sub‐storm injections play a role in amplifying chorus waves in the magnetosphere. The wave‐particle interaction leads to rapid heating and acceleration of electrons from 10's of keV to 10's of MeV energies. In this work, we examined the changes in the radiation belt during geomagnetic storm events by studying the RBSP REPT, solar wind, AL, SML, and Dst data in conjunction with the WINDMI model of the magnetosphere. The field‐aligned current output from the model is integrated to generate a proxy E index for various energy bands. These E indices track electron energization from 40 KeV to 20 MeV in the radiation belts. The indices are compared to RBSP data and GOES data. Our proxy indices correspond well to the energization data for electron energy bands between 1.8 and 7.7 MeV. Each E index has a unique empirical loss rate term (τ_L), an empirical time delay term (τ_D), and a gain value, that are fit to the observations. These empirical parameters were adjusted to examine the delay and charging rates associated with different energy bands. We observed that theτ_Landτ_Dvalues are clustered for each energy band.τ_Landτ_Dconsistently increase going from 1.8 to 7.7 MeV in electron energy fluxE_eand the dropout interval increases with increasing energy level. The average trend of Δτ_D/ΔE_ewas 4.1 hr/MeV and the average trend of Δτ_L/ΔE_ewas 2.82 hr/MeV. 

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5. Molecular epidemiology and pathogenomics of extended-spectrum beta-lactamase producing- Escherichia coli and - Klebsiella pneumoniae isolates from bulk tank milk in Tennessee, USA

   https://doi.org/10.3389/fmicb.2023.1283165  

   Gelalcha, Benti D; Mohammed, Ruwaa I; Gelgie, Aga E; Kerro_Dego, Oudessa (November 2023, Frontiers in Microbiology)

   IntroductionThe rise in extended-spectrum beta-lactamase (ESBL)-producingEnterobacteriaceaein dairy cattle farms poses a risk to human health as they can spread to humans through the food chain, including raw milk. This study was designed to determine the status, antimicrobial resistance, and pathogenic potential of ESBL-producing -E. coliand -Klebsiellaspp. isolates from bulk tank milk (BTM). MethodsThirty-three BTM samples were collected from 17 dairy farms and screened for ESBL-E. coliand -Klebsiellaspp. on CHROMagar ESBL plates. All isolates were confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and subjected to antimicrobial susceptibility testing and whole genome sequencing (WGS). ResultsTen presumptive ESBL-producing bacteria, eightE. coli, and twoK. pneumoniaewere isolated. The prevalence of ESBL-E. coliand -K. pneumoniaein BTM was 21.2% and 6.1%, respectively. ESBL-E. coliwere detected in 41.2% of the study farms. Seven of the ESBL-E. coliisolates were multidrug resistant (MDR). The two ESBL-producingK. pneumoniaeisolates were resistant to ceftriaxone. Seven ESBL-E. colistrains carry thebla_CTX-Mgene, and five of them co-harboredbla_TEM-1. ESBL-E. colico-harboredbla_CTX-Mwith other resistance genes, includingqnrB19,tet(A),aadA1,aph(3’’)-Ib,aph(6)-Id),floR,sul2, and chromosomal mutations (gyrA, gyrB, parC, parE, and pmrB). MostE. coliresistance genes were associated with mobile genetic elements, mainly plasmids. Six sequence types (STs) ofE. coliwere detected. All ESBL-E. coliwere predicted to be pathogenic to humans. Four STs (three ST10 and ST69) were high-risk clones ofE. coli. Up to 40 virulence markers were detected in allE. coliisolates. One of theK. pneumoniaewas ST867; the other was novel strain.K. pneumoniaeisolates carried three types of beta-lactamase genes (bla_CTX-M,bla_TEM-1andbla_SHV). The novelK. pneumoniaeST also carried a novel IncFII(K) plasmid ST. ConclusionDetection of high-risk clones of MDR ESBL-E. coliand ESBL-K. pneumoniaein BTM indicates that raw milk could be a reservoir of potentially zoonotic ESBL-E. coliand -K. pneumoniae. 

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