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In this paper, we propose a freeze tweezer using the freezing force of a small volume of nucleotide ice to manipulate mini/micro objects in an aqueous state. Several prototypes of such a device based on the Joule-Thompson throttling effect have been fabricated and there have been preliminary demonstrations of their applicability in manipulating a wide variety of objects. By regulating the freezing conditions of the cooler, an ice ball can be formed between the tweezer tip and the object it contacts and then the object can be picked up. This freezing force is strong enough to manipulate objects with any shape, electric charge, light or heavy, biological or non-living, on the condition that the contact area can be frozen. Successful manipulation of a series of specific objects presented in this paper indicates that it would be much easier for the freeze tweezer to handle objects with smaller size. Therefore, further nanoscale freeze tweezers following the same idea as above can be put forward; this is expected to have exciting applications in micro/nano engineering field. Furthermore, theoretical analysis and experiments have been performed to quantify the response time of the freeze tweezer and the mechanical force generated on the tweezer tip. This study has also raised quite a few new fundamental issues related to the fabrication and practices of the freeze tweezer.

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While the study of personality differences is a traditional psychological approach in entrepreneurship research, economic research directs attention towards the entrepreneurial ecosystems in which entrepreneurial activity are embedded. We combine both approaches and quantify the interplay between the individual personality make-up of entrepreneurs and the local personality composition of ecosystems, with a special focus on person-city personality fit. Specifically, we analyse personality data from N = 26,405 Chinese residents across 42 major Chinese cities, including N = 1091 Chinese entrepreneurs. Multi-level polynomial regression and response surface plots revealed that: (a) individual-level conscientiousness had a positive effect and individual-level agreeableness and neuroticism had a negative effect on entrepreneurial success, (b) city-level conscientiousness had a positive, and city-level neuroticism had a negative effect on entrepreneurial success, and (c) additional person-city personality fit effects existed for agreeableness, conscientiousness and neuroticism. For example, entrepreneurs who are high in agreeableness and conduct their business in a city with a low agreeableness level show the lowest entrepreneurial success. In contrast, entrepreneurs who are low in agreeableness and conduct their business in a city with a high agreeableness level show relatively high entrepreneurial success. Implications for research and practice are discussed.

Effect of the nanomatrix structure on mechanical properties of natural rubber was investigated in relation to the strain‐induced crystallization. Structure of natural rubber was analyzed through Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction measurement and transmission electron microscopy. The nanomatrix of the non‐rubber components was found to be inevitably formed in natural rubber, in which natural rubber particles linking to fatty acids were dispersed in the nanomatrix of the proteins and phospholipids. The nanomatrix disappeared after deproteinization of natural rubber with urea. Tensile strength and modulus of natural rubber were reduced by removal of the fatty acids and the proteins, which resulted in disappearance of the nanomatrix structure. The effect of fatty acids on the crystallization of natural rubber in small particles as a dispersoid was proved by tensile test of blend of natural rubber and styrene butadiene rubber. Copyright © 2016 John Wiley & Sons, Ltd.

This paper is aimed at comprehensively investigating the dynamic low-frequency electrical impedance (DLFI) of biological materials during the processes of freezing, thawing and heating, and combinations of them. Electrical impedance detection (EID) was proposed as a means of rapidly evaluating the viability of biological materials subject to freezing or thermal injury (processes expected to be significant in the practices of cryobiology and hyperthermia). Using two experimental setups, the DLFI for selected biological materials (fresh pork and fish) under various freezing and heating conditions was systematically measured and analyzed. Preliminary results demonstrate that damage that occurs to a biological material due to freezing or heating could result in a significant deviation in its electric impedance value from that of undamaged biomaterials. Monitoring impedance change ratios under various freezing and heating conditions may offer an alternative strategy for assessing the amount of damage sustained by biomaterials subject to cryosurgery, cryopreservation and hyperthermia. Implementation of the present method in order to develop a new micro-analysis or biochip system is also suggested.