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This paper measures the level and growth of total factor productivity (TFP) of public hospitals in Victoria, Australia, using an index number approach. We further examine the persistence of productivity over time, and the extent to which productivity varies with hospital characteristics such as hospital size. Hospital administrative data from Victoria from 2007–08 to 2011–12 are used. We find substantial variation in TFP across hospitals: large hospitals perform significantly better than small hospitals, both in TFP level and growth. Productivity level is highly persistent over time, but not productivity growth.

Microbial induced calcium carbonate precipitation (MICP) is widely common in nature, which belongs to biomineralization, and has been explored carefully in recent decades. The research studied the main factors including temperature, initial pH value and Ca2+ concentration on bacterial growth and carbonic anhydrase activity by Bacillus mucilaginosus producing extracellular carbonic anhydrase, and revealed the biomineralization process of MICP by Ca2+ concentration and calcification rate in alkali environment. Meanwhile, microbial healing agent containing spores and calcium nitrate was prepared for the early age concrete cracks. The self-healing efficiency was assessed by crack closure rate, water permeability repair rate, healing depth and so on. Moreover, the precipitations generated at the crack mouth of specimens were analyzed by scanning electron microscope (SEM) equipped with an energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). After 28 d healing time of dry-wet cycles, compared with reference, the crack closure rate with the crack width up to 0.339 mm could reach 95.62%, the water permeability repair rate was 87.54%. In addition, the precipitations generated were most at the crack surface, with the increase of the crack depth, the precipitations gradually decreased. XRD analysis showed that the precipitations at the crack mouth were calcite CaCO3. Meanwhile, the self-healing mechanism of mortar cracks was discussed in detail. What’s more, the CA produced by the bacteria could accelerate the hydration of CO2 in the air, and the mineralization reaction efficiency was also high. In particular, there is no other pollution in the whole mineralization process, and the self-healing system is environmentally friendly, which provides a novel idea and method for the application of microbial self-healing concrete.

The study investigated the modification mechanism of modified ground calcium carbonate (GCC) mineral powder using in asphalt concrete. Two types of Titanate coupling agents, namely, K38S (TCA-K38S) and 201 (TCA-201), as well as sodium stearate coupling agent, were adopted to prepare modified GCC. The optimized preparation process was obtained through the orthogonal test. Two kinds of modified GCC were preferably selected to prepare asphalt concrete according to modification mechanism characterization, their performance was analyzed and evaluated at macro and micro levels. The study results show that, the optimal scheme of sodium stearate modified GCC is modification temperature of 80°C, modification time of 50 min, modifying agent dosage of 2.0%. The crystal structure of GCC remains unchanged after modification, with the original lattice structure being maintained. TCA-201 and sodium stearate exhibit better coating properties than that of TCA-K38S. The contact angles of TCA-201 and sodium stearate modified GCC are larger than that of TCA-K38S modified GCC. The in-service performance of AC-13C asphalt concrete modified with sodium stearate is found to be superior to that of TCA-201 modified AC-13C asphalt concrete. Compared with the unmodified AC-13C asphalt concrete, the Marshall modulus, residual stability, freeze-thaw splitting strength ratio, and maximum flexural tensile strain of sodium stearate modified AC-13C asphalt concrete are increased by 54.55%, 2.73%, 10.47%, and 26.41% respectively. This paper provides theoretical guidance for the application of GCC mineral powder in asphalt concrete.