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The 2017 edition of expert consensus onclassification and clinical strategy of constipation was released in March 2018. This artide makes a joint interpretation of it with the Guideline for surgical diagnosis and treatment of constipation (2017 edition). The similarities and differences between the two mainly include: (1) The concept of constipation is basically the same, the main difference is that the consensus puts forward the association between constipation and mental disorders. (2) For constipation in terms of etiology, examination methods and evaluation, the consensus does not mention the etiology, but the examination methods are completely consistent. The reference standard of mental and psychological assessment is added in the consensus. (3) For the diagnosis of constipation, the diagnostic criteria and classification of constipation are specified in the guideline, and only the classification of constipation is mentioned briefly, while the consensus further develops the three different degrees of constipation. (4) For the treatment of constipation, the basic principles are the same. In the description of the specific treatment plan, the guideline divides the treatment methods of constipation into two categories: non-surgical treatment and surgical treatment, and then focuses on the suitability and specific operation of surgical treatment, while the consensus focuses more on coping strategies and treatment options for different degrees of constipation, including how to deal with the unavoidable mental and psychological disorders in the diagnosis and treatment of constipation questions. It can be seen that the consensus is a supplement and improvement of the guideline for surgical diagnosis and treatment of constipation. The consensus provides more targeted and applicable clinical reference ideas for clinical practice from different perspectives, especially the better auxiliary clinical decision-making after the quantification of the classification standard of constipation.

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The methanol to hydrocarbon (MTH) process provides an efficient route for the conversion of carbon-based feedstocks into olefins, aromatics and gasoline. Still, there is room for improvements in product selectivity and catalytic stability. This task calls for a fundamental understanding of the formation, catalytic mechanism and degradation of active sites. The autocatalytic feature of the MTH process implies that hydrocarbons are active species on the one hand and deactivating species on the other hand. The steady-state performance of such species has been thoroughly studied and reviewed. However, the mechanism of formation of the initial hydrocarbon species (i.e.; the first C-C bond) and the evolution of active species into deactivating coke species have received less attention. Therefore, this review focuses on the significant progress recently achieved in these two stages by a combination of theoretical calculations, model studies, operando spectroscopy and catalytic tests.

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We investigate the quantum tunneling of Bose-Einstein condensates in optical lattices under gravity in the "Wannier-Stark localization" regime and "Landau-Zener tunneling" regime. Our results agree with experimental data [B. P. Anderson et al., Science 282, 1686 (1998); F. S. Cataliotti et al., Science 293, 843 (2001)]. We obtain the total decay rate which is valid over the entire range of temperatures, and show how it reduces to the appropriate results for the classical thermal activation at high temperatures, the thermally assisted tunneling at intermediate temperatures, and the pure quantum tunneling at low temperatures. We design an experimental protocol to observe this new phenomenon in further experiments.

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A study was carried out on the intrahepatic topography and histological structure of bile duct system and its relations to arterial and portal system in healthy fresh bodies. It was found that in 83%-85% of the cases, the bile duct, the arterial and portal system branch off at about the same level, a physiological stricture could be found at each bifurcation of the bile duct. Collagenic fibers and elastic fibers go transversely, longitudinally and obliquely within the bile duct wall at the level of its bifurcations giving the lumen limited room to expand, whereas fibers go only transversely and longitudinally at the trunk of all grades of the bile duct system. Basing on the observations, the authors discussed the hydrokinetics of the bile and its relations to cholelithiasis.

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