Using Mechanochemistry to Activate Commodity Plastics as Initiators for Radical Chain Reactions of Small Organic Molecules.

Radical initiators such as azo compounds and organic peroxides have been widely used to facilitate numerous transformations of free radicals, which enable the efficient synthesis of structurally complex molecules, natural products, polymers, and functional materials. However, these high-energy reagents are potentially explosive and thus often require special precautions or delicate operating conditions. We postulated that a more convenient and safer alternative for radical chain initiation could be developed by mechanical activation of thermodynamically stable covalent bonds. Here, we show that commodity plastics such as polyethylene and poly(vinyl acetate) are capable of acting as efficient initiators for radical chain reactions under solvent-free mechanochemical conditions. In this approach, polymeric mechanoradicals, which are generated by homolytic cleavage of the polymer chains in response to the applied mechanical energy provided by ball milling, react with tris(trimethylsilyl)silane to initiate radical chain dehalogenation of organic halides. Preliminary calculations support our proposed force-induced radical chain mechanism.

Sensitive Detection of Nitrite and Nitrate in Seawater by 222 nm UV-Irradiated Photochemical Conversion to Peroxynitrite and Ion Chromatography-Luminol Chemiluminescence System.

Sensitive detection methods for nitrite (NO2-) and nitrate (NO3-) ions are essential to understand the nitrogen cycle and for environmental protection and public health. Herein, we report a detection method that combines ion-chromatographic separation of NO2- and NO3-, on-line photochemical conversion of these ions to peroxynitrite (ONOO-) by irradiation with a 222 nm excimer lamp, and chemiluminescence from the reaction between luminol and ONOO-. The detection limits for NO2- and NO3- were 0.01 and 0.03 µM, respectively, with linear ranges of 0.010-2.0 and 0.10-3.0 µM, respectively, at an injection volume of 1 µL. The results obtained by the proposed method for seawater analysis corresponded with those of a reference method (AutoAnalyzer based on the Griess reaction). As luminol chemiluminescence can measure ONOO- at picomolar concentrations, our method is expected to be able to detect NO2- and NO3- at picomolar concentrations owing to the high conversion ratio to ONOO- (>60%), assuming that contamination and background chemiluminescence issues can be resolved. This method has the potential to emerge as an innovative technology for NO2- and NO3- detection in various samples.

Responsiveness of beef cattle (Bos taurus) to human approach, novelty, social isolation, restraint and trade-offs between feeding and social companionship.

This study investigated responsiveness of beef cattle to various environmental stimuli by subjecting 15-16 Japanese Black cows to five tests repeated twice. Within individual behavioral measures, cows were moderately (repeatability = 0.54-0.70) or highly (repeatability = 0.74-0.89) consistent in flight distance during grazing and resting in the human approach tests, maximum distance from the group pen and the number of total and different feed tub visits in the feeding-sociability trade-off test, and unwillingness to enter the restraint, movement under restraint and flight speed after release from restraint in the social isolation and restraint test. By contrast, cows were not consistent in the latency to make the first contact and the number of contacts with novel object(s) in the novelty test (repeatability = 0.24-0.39). Across behavioral measures in different tests, cows showed no consistency (P ≥ 0.05) in any combinations of measures from the two human approach tests, the trade-off test and the social isolation and restraint test. In conclusion, human approach (particularly during resting), feeding-sociability trade-off and social isolation and restraint situations can be used for evaluating personality in Japanese Black cows, while the value of the novelty test needs to be reexamined.

A molecular epidemiological survey of Babesia, Hepatozoon, Ehrlichia and Anaplasma infections of dogs in Japan.

Tick-borne diseases are often encountered in canine clinical practice. In the present study, a molecular epidemiological survey of dogs in Japan was conducted to understand the prevalence and geographical distribution of Babesia spp., Hepatozoon spp., Ehrlichia spp. and Anaplasma spp. Pathogen-derived DNA in blood samples obtained from 722 dogs with a history of exposure to ticks and/or fleas was examined by PCR. The prevalence of Babesia gibsoni, Babesia odocoilei-like species, Hepatozoon canis and Ehrlichia spp./Anaplasma spp. was 2.4% (16/722), 0.1% (1/722), 2.5% (18/722) and 1.5% (11/722), respectively. While B. gibsoni and Ehrlichia spp./Anaplasma spp. were detected in the western part of Japan, H. canis was detected in Tohoku area in addition to western and central parts of Japan.