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A pulse radiolysis study of the formation and decay of the triplet excited state of liquid pyridine has been performed using quenching techniques. The pyridine triplet excited state is observed with an absorption band at lambda = 310 nm and has a first-order decay with a lifetime of 72 ns. Stern-Volmer plots of the quenching of the pyridine triplet excited state with anthracene, naphthalene, and biphenyl give its yield to be 1.3 molecules/100 eV. This value is very similar to the previously determined yield of 1.25 molecules/100 eV for dipyridyl, the predominant condensed-phase product in the gamma-radiolysis of liquid pyridine. The rate coefficient for pyridine triplet excited-state scavenging by oxygen is estimated to be 6.6 x 10(9) M(-1) s(-1). Oxygen may also scavenge the electron precursor to the pyridine triplet excited state, whereas nitrous oxide is observed to have little effect. A pyridyl radical-pyridine (dimer) complex produced in the pulse radiolysis of neat liquid pyridine is detected at lambda = 390 nm and is consistent with iodine scavenging effects. Formation of the pyridiniumyl radical cation-pyridine charge-transfer complex is proposed to be insignificant in liquid pyridine.

SUMMARY: To develop a radical polyad~tion reaction of 2 -b e n z o y l o x y~n t~u o r o p #~n e [CFz=C(CF,)-OCOC&&] (BPFP) with tetrahydrofuran (THF), the reactions of bis(a-trifluoromethyl-@-difluorovinyl) terephthalate [CF2=C(CF3)OCOC&COOC(CF3)~F~J (BFP) with THF and of BPFP with 1,4-dioxane were investigated as model reactions to form 1 : 1 and 1 : 2 addition products of BFP with THE This evidenced that THF is monofunctional, and dioxane i s bifunctional since the 1 : 1 and 2: 1 addition products of BPEP with dioxane were formed. The polyaddition reaction of BFP with dioxane turned out to produce a white powdery substance which was found to possess a mole ratio of BFP units to dioxane units in the polymers of 1 : 1. The highest molecular weight obtained was M, = 9.9 x lo3. Int~ductionFluorinated vinyl monomers have unusual and interesting reactivities compared to hydrocarbon analogues. Numerous fluorinated vinyl monomers are hardly polymerized with radical initiators whereas the t e t r~u o r~t h y l e n e polymer is readily produced under free radical conditions. Trifluorovinyl and a-h flu or om ethyl vinyl compounds have scarcely been polymerized with radical and anionic initiators although hydrocarbon analogues are easily polymerized under conventional polymerization conditions". Though the electron density of vinyl groups should be decreased by the e~e c t r o n -w~~~~a w i n g inductive effect of fluorine or fluoromethyl groups, the polymerization of 2-benzoyloxypentafluoropropene (BPFP) was difficult under anionic conditions. During the investigation of the radical polymerization reactivity of BPFP, the radical addition reaction of BPFT with THF was found to produce a 1 : 1 adduct of the vinyl groups with THF in high yields in the presence of benzoyl peroxide (BPO) at 60°C in THF as a solvent2). The postulated mechanism is shown in Scheme 1. The benzoyloxy radical prepared from BPO abstracts the hydrogen at the 2-position of THE The addition reaction of the THF radical with BPFP takes place to form the radical at the aposition of BPFP w~i c~ abstracts a hydrogen from another THF molecule. The reaction proceeds via this

SUMMARY A microfluidic system using electrochemical biosensor for continuous lactic acid (LA) monitoring at the skin's surface was fabricated and tested. The system consists of a micro flow‐cell for sampling LA at the skin's surface and a microfluidic LA biosensor based on a redox reaction of osmium wired horseradish peroxidase. Our system measures excreted LA by dissolving whole secretion in phosphate buffered saline (PBS), which was supplied into the microchannel as carrier flow. The measurement system was utilized in the real‐time monitoring of LA secretion during stationary bike exercises. Exercise intensities were regulated by heart rates (HRs) and the sampling device was attached on the right upper arm of the volunteer. During the exercise, PBS was circulated into the measurement system. As a result, change of LA levels correlated with the volunteer's physiological status was confirmed. Secretion of LA was estimated to be 4.50 μg/cm2/min when the intensity of exercise was high (HR: 160 bpm) and the signal decreased to the initial level after the exercise. This indicates that our system is suitable for not only the assessment of exercise intensity, but also useful in evaluation of metabolic activity.

The radiation chemical yields of the products derived from the triplet excited state produced in the radiolysis of liquid benzene with gamma-rays, 10 MeV 4He ions, and 10 MeV 12C ions have been determined. Iodine scavenging techniques have been used to examine the formation and role of radicals, especially the H atom and phenyl radical. For all irradiation types examined here, the increase in hydrogen iodide yields with increasing iodine concentration matches the increase in iodobenzene yields. This agreement suggests that the benzene triplet excited state is the common precursor for the H atom and the phenyl radical. Pulse radiolysis studies in liquid benzene have determined the rate coefficients for the reactions of phenyl radicals with iodine and with the solvent benzene to be 9.3 x 10(9) M(-1) s(-1) and 3.1 x 10(5) M(-1) s(-1), respectively. Direct measurements of polymer formation, which refers to trimers (C18) and higher order compounds (>C18), in liquid benzene radiolysis using gamma-rays, 4He ions, and 12C ions at relatively high doses have been performed using gel permeation chromatography. The yields of trimers increase from gamma-rays to 12C ions due to the increased importance of intratrack radical-radical reactions that can be scavenged by the radical scavenging reactions of iodine. On the other hand, the >C18 product yields decrease from gamma-rays to 12C ions. The structure of the polymer consists of a partly saturated ring as determined by infrared and gas chromatography/mass spectrometry studies. A schematic representation for the radiolytic decomposition of the benzene triplet excited state is presented.

This study aimed to perform a comparative analysis of postoperative results between lumbar degenerative spondylolisthesis (LDS) treated with oblique lateral interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) from the Chiba spine surgery registry database. Sixty-five patients who underwent single-level OLIF (O group) for LDS with ≥ 3 years’ follow-up were retrospectively reviewed. The control group comprised 78 patients who underwent single-level TLIF (T group). The analyzed variables included global alignment, radiological parameters of fused segments, asymptomatic and symptomatic ASD incidence, clinical outcomes at 3 years postoperatively using the Japanese Orthopedic Association Back Pain Evaluation Questionnaire data, visual analogue scale scores for low back pain, lower extremity pain, and lower extremity numbness. There was no significant change in global alignment between the two groups. The rate of improvement in anterior intervertebral disc height was not significantly different between the groups at 1-month postoperatively. However, at the final evaluation, the anterior intervertebral disc height and incidence of asymptomatic ASD were significantly higher in the O group. There was no significant difference in symptomatic ASD, reoperation cases, or clinical results between groups. Thus, single-level OLIF can maintain the corrected disc height, but as it has no effect on global alignment, its benefit is limited.

ZEP520A (1:1 copolymer of α-chloromethacrylate and α-methylstyrene, ZEON) is a main-chain scission-type positive-tone resist used for electron beam (EB) lithography and is known for its high sensitivity and high resolution. In this study, ZEP520A was irradiated using a 100 kV EB, and the decomposition mechanisms were analyzed by gel permeation chromatography, Fourier transform IR spectroscopy, NMR spectroscopy, and pulse radiolysis. Chlorines were confirmed to easily dissociate as Cl- ions (dissociative electron attachment, DEA) and ZEP520A underwent β-scission. Multiple channels could be considered for the main-chain scission, including DEA and the charge transfer complex between phenyl radical cations and Cl- ions.