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As one of the perennial vegetable varieties grown in the south of Yangtze River in China, Brassica chinensis L. can be produced and supplied to the market all year round and has high economic value. However, there is little direct literature on postharvest heat treatment of Brassica chinensis L. In this study, Peroxidase (POD) was extracted from Brassica chinensis L. leaves and its enzymatic characteristics such as optimal pH, optimal temperature, catalytic activation energy, Km and Vmax, thermal stability and thermal denaturation activation energy were discussed. The results showed that with o-phenylenediamine as the hydrogen donor substrate of POD and hydrogen peroxide as the peroxide substrate, the optimal pH was 6.8, the optimal reaction temperature was 40°C and the activation energy of the catalytic reaction was 35.34 kJ/mol for POD in Brassica chinensis L. leaves. As a dual substrate reaction, when o-phenylenediamine was used as the substrate, the Km value of POD was 1.143 mmoL/L and Vmax was 142.86 U. When hydrogen peroxide was used as the substrate, the Km value of POD was 2.778 mmoL/L and Vmax was 111.11 U. Thermal inactivation studies showed first-order inactivation kinetic characteristics and the Arrhenius plot yielded a straight line with a slope equivalent to the thermal denaturation activation energy of POD at 199.54 kJ/moL. The thermal inactivation rate of POD varied significantly between 70 and 80°C (the rate constant k ranged from -0.446 to -0.970), indicating that the thermal denaturation of POD may occur between 70 and 80°C. It is expected that the above data would be beneficial to the optimization of quality control parameters in postharvest heat treatment and cold-chain transportation of Brassica chinensis L.

As one of the perennial vegetable varieties grown in the south of Yangtze River in China, Brassica chinensis L. can be produced and supplied to the market all year round and has high economic value. However, there is little direct literature on postharvest heat treatment of Brassica chinensis L. In this study, Peroxidase (POD) was extracted from Brassica chinensis L. leaves and its enzymatic characteristics such as optimal pH, optimal temperature, catalytic activation energy, Km and Vmax, thermal stability and thermal denaturation activation energy were discussed. The results showed that with o-phenylenediamine as the hydrogen donor substrate of POD and hydrogen peroxide as the peroxide substrate, the optimal pH was 6.8, the optimal reaction temperature was 40°C and the activation energy of the catalytic reaction was 35.34 kJ/mol for POD in Brassica chinensis L. leaves. As a dual substrate reaction, when o-phenylenediamine was used as the substrate, the Km value of POD was 1.143 mmoL/L and Vmax was 142.86 U. When hydrogen peroxide was used as the substrate, the Km value of POD was 2.778 mmoL/L and Vmax was 111.11 U. Thermal inactivation studies showed first-order inactivation kinetic characteristics and the Arrhenius plot yielded a straight line with a slope equivalent to the thermal denaturation activation energy of POD at 199.54 kJ/moL. The thermal inactivation rate of POD varied significantly between 70 and 80°C (the rate constant k ranged from -0.446 to -0.970), indicating that the thermal denaturation of POD may occur between 70 and 80°C. It is expected that the above data would be beneficial to the optimization of quality control parameters in postharvest heat treatment and cold-chain transportation of Brassica chinensis L.

Insurance profits in non-life insurance markets display a large fluctuation that may make it hard for insurance companies to control their operating volatility. By taking into account asymmetries in dynamics of insurance profits, this paper provides empirical evidence of the visualised cycles in insurance markets and relevant underwriting strategies of insurance companies. The results hint at the possible existence of overconfidence in underwriting activities when the underwriting result turns bad. Compared with the whole insurance industry, insurance companies engage more speculative behaviour in underwriting activities on the general liability insurance. For regulation purposes, the government should maintain more disciplined underwriting policies of insurance companies in different insurance lines in order to avoid irrational pricing strategies and improve the economic efficiency of insurance supply.

Perfobond Leister Rib (PBR) is found to improve the bond strength in concrete-filled hollow section and the capacity of the steel plate to resist local buckling. An experimental investigation of 12 test specimens is firstly carried out on the behavior of concrete-filled square hollow section CFSHS) stub columns with PBR. To examine different mechanical behaviors of the columns utilized in bridge or building structure, different loading methods are investigated; e.g., loading through steel alone, loading through concrete alone and loading through the whole cross section. The failure mode, strain distribution, ultimate strength and the confinement of the concrete core offered by the steel tube are studied. The test results showed that CFSHS tubular columns with PBR are emulative of the conventional columns. PBR can make the steel tube and filled-in concrete work together, which results in the axial load shared by hollow steel section and filled-in concrete section regardless of loading through steel or concrete alone. The axial strain distribution model of steel tube section along the height for CFSHS with PBR is proposed.

Insurance profits in non-life insurance markets display a large fluctuation that may make it hard for insurance companies to control their operating volatility. By taking into account asymmetries in dynamics of insurance profits, this paper provides empirical evidence of the visualised cycles in insurance markets and relevant underwriting strategies of insurance companies. The results hint at the possible existence of overconfidence in underwriting activities when the underwriting result turns bad. Compared with the whole insurance industry, insurance companies engage more speculative behaviour in underwriting activities on the general liability insurance. For regulation purposes, the government should maintain more disciplined underwriting policies of insurance companies in different insurance lines in order to avoid irrational pricing strategies and improve the economic efficiency of insurance supply.

Non-life insurance prices may fluctuate due to economic and/or institutional factors; occasionally, the changes are cyclical. While the majority of previous studies relating to insurance price dynamics adopt data from developed economies, this paper uses data from China to provide new evidence. This study tests the long-term and short-term effects of real gross domestic product (GDP), interest rate and rate of stock market return on the prices of different lines of non-life insurance, i.e., property-liability insurance and personal accident insurance. The results indicate that the price dynamics of property-liability insurance are generally similar to those of developed countries, except for the effect of GDP, while price determination of personal accident insurance seems to be affected by a wider range of economic and institutional variables and has its own features. The price dynamics of non-life insurance in China have been identified as being connected to the country-specific economic and institutional environments.

U radu je primijenjen hi-kvadrat test i binarna logistička regresija u analizi faktora koji dovode do teških sudara na brdskim cestama na jugoistoku Kine i određivanju njihova utjecaja na stupanj težine sudara u svrhu poduzimanja odgovarajućih mjera za poboljšanje sigurnosti na cesti. Rezultati su pokazali da mlađi i stariji vozači, žene, vožnja vikendom i rano ujutro, doprinose težini sudara. Uz to, vjerojatnije je da će se teški sudari dogoditi u proljeće, ljeto i jesen, nego zimi. Važnost dobivenih rezultata je u tome što vozači mogu razumjeti specifične karakteristike sudara na brdskoj autocesti na jugoistoku Kine te se mogu poduzeti odgovarajuće mjere da se stupanj sigurnosti poveća. Stoga se u radu daju sugestije za povećanje sigurnosti; mlađe i starije vozače treba upozoriti postavljanjem raznih prometnih znakova ili propagandom; vozačicama se savjetuje da ne voze na nekim dijelovima te ceste; upozorenja bi trebalo postaviti o pažljivoj vožnji noću naročito između 0 i 5:59 ujutro., This paper adopted chi-square test and binary logistic regression to analyse factors about mountainous freeway crash severity level in the southeast of China and to determine the factor impact on crash severity level to make corresponding measures to improve road safety. Results of this paper indicated that younger and older drivers, female drivers, weekends and driving early in morning all make contribution to severe mountainous freeway crashes. Besides, it is more likely to occur in severe crash in spring, summer and autumn compared to that in winter. The importance of study results to audience is that road users can understand the specific characteristics of mountainous freeway crashes in southeast of China and corresponding measurements could be made to improve the safety level. Therefore, this paper proposed some suggestions to improve mountainous freeway safety: younger and older drivers should be told the driving weakness by means of variable message sign or propaganda; female drivers are not encouraged to drive in some special mountainous freeway sections; traffic designs about careful driving at night are supposed to be set especially between 0 am and 5:59 am.