Extremely large magnetoresistance (XMR) was recently discovered in many non-magnetic materials, while its underlying mechanism remains poorly understood due to the complex electronic structure of these materials. Here, we report an investigation of the α-phase WP2, a topologically trivial semimetal with monoclinic crystal structure (C2/m), which contrasts to the recently discovered robust type-II Weyl semimetal phase in β-WP2. We found that α-WP2 exhibits almost all the characteristics of XMR materials: the near-quadratic field dependence of MR, a field-induced up-turn in resistivity following by a plateau at low temperature, which can be understood by the compensation effect, and high mobility of carriers confirmed by our Hall effect measurements. It was also found that the normalized MRs under different magnetic fields has the same temperature dependence in α-WP2, the Kohler scaling law can describe the MR data in a wide temperature range, and there is no obvious change in the anisotropic parameter γ value with temperature. The resistance polar diagram has a peanut shape when field is rotated in ac plane, which can be understood by the anisotropy of Fermi surface. These results indicate that both field-induced-gap and temperature-induced Lifshitz transition are not the origin of up-turn in resistivity in the α-WP2 semimetal. Our findings establish α-WP2 as a new reference material for exploring the XMR phenomena.

Active non-volatile taste components, including free amino acids, the flavor of the 5'-nucleotides, lactic acid, succinic acid and 4 kinds of inorganic ions (chloride, sodium, potassium, phosphate ions) of the viscera and the adductor muscles of oysters (Ostrea rivularis) were analyzed. Additionally, a contrast experiment was conducted to highlight the difference in tastes between adductor muscle extracts and viscera extracts. Taste activity values (TAVs) and equivalent umami concentration (EUC) were calculated for samples of the two tissues. Our results showed that the total amount of free amino acid in the adductor muscle was about 5 times as that in the viscera; and the TAVs of five free amino acids in the muscle exceeded 1, while TAVs of all amino acids found in the viscera were below 1. Additionally, the EUC of the adductor muscle was about 35 times as that of the viscera. The TAVs of succinic acid were above 1 in both tissues. Cl − contents in the muscle and the viscera were approximately equal, but the contents of the other three inorganic ions we tested were different. Furthermore, the results of sensory tests showed that the adductor muscle was preferred to the viscera. In conclusion, the taste of the adductor muscle was found to be far more intense and preferable to that of the viscera.Keywords: oyster, non-volatile taste components, viscera, adductor muscle, umami, TAV *To whom correspondence should be addressed. E-mail: chaohuaz@sohu.com IntroductionSeafood condiments are frequently used in our daily life to enhance the flavor of our food. Several studies have successfully identified the active flavor compounds in seafood (Spurvey and Shahidi, 1998;Fuke and Konosu, 1991;Ninomiya, 2002). Generally speaking, flavor compounds include volatile compounds and nonvolatile components, and the latter consists of water-soluble and low-molecularweight components. The nonvolatile components of flavor compounds are considered to be the source of flavor and are classified into nitrogenous (free amino acids, nucleotides, organic bases and related compounds) and non-nitrogenous compounds (sugars, organic acids and inorganic compounds) with the exception of vitamins, minerals and pigments (Konosu and Yamaguchi, 1982). However, taste is not only related to the concentration of such compounds, but also influenced by their detection thresholds. That is why taste activity value (TAV) is widely used in evaluating the taste impact of the individual taste active compound in the food system. TAV is the ratio of concentration of an individual compound divided by its corresponding taste identification threshold. If the TAV value is above 1, the individual compound is considered to be active in food taste (Rotzoll et al., 2006; charbert and Hofmann, 2005;Schlichtherle and Grosch, 1998). Moreover, Mau (2005) introduced an alternative metric called Equivalent Umami Concentration (EUC) that is based on the concentration of nonvolatile components. EUC is the concentration of MSG equivalenting to the umami intensity given by the mi...

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Continuous glucose monitoring (CGM) can miniinvasively track blood glucose fluctuation and reduce the risk of hyperglycemia and hypoglycemia, and this is is in great demand for diabetes management. However, cost-effective manufacture of CGM systems with continuously improved convenience and performance is still the persistent goal. Herein, we developed a smartphonecontrolled and microneedle (MN)-based wearable CGM system for long-term glucose monitoring. The CGM system modified with a sandwich-type enzyme immobilization strategy can satisfy the clinical requirement of interstitial fluid (ISF) glucose monitoring for 14 days with a mean absolute relative difference of 10.2% and a cost of less than $15, which correlated well with the commercial glucometer and FDA-approved CGM system FreeStyle Libre (Abbott Inc., Illinois, USA). The self-developed CGM system is demonstrated to accurately monitor glucose fluctuations and provide abundant clinical information. It is better to find the cause of individual blood glucose changes and beneficial for the guide of precise glucose control. On the whole, the intelligently wearable CGM system may provide an alternative solution for home-care diabetes management.

We performed calculations of the electronic band structure and the Fermi surface, measured the longitudinal resistivity ρxx (T,H), Hall resistivity ρxy (T,H), and magnetic susceptibility as a function of temperature at various magnetic fields for VAs2 with a monoclinic crystal structure. The band structure calculations show that VAs2 is a nodal-line semimetal when spin-orbit coupling is ignored. The emergence of a minimum at around 11 K in ρxx (T) measured at H = 0 demonstrates that some additional magnetic impurities (V4+, S = 1/2) exist in VAs2 single crystals, inducing Kondo scattering, evidenced by both the fitting of ρxx (T) data and the susceptibility measurements. It is found that a large positive magnetoresistance (MR) reaching 649% at 10 K and 9 T, its nearly quadratic field dependence, and a field-induced up-turn behavior of ρxx (T) also emerge in VAs2, although MR is not so large due to the existence of additional scattering compared with other topological nontrivial/trivial semimetals. The observed properties are attributed to a perfect charge-carrier compensation, which is evidenced by both the calculations relying on the Fermi surface and the Hall resistivity measurements. These results indicate that the compounds containing V (3d 3 4s 2) element can be as a platform for studying the influence of magnetic impurities to the topological properties.