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In this paper, uniformly unconditionally stable first and second order finite difference schemes are developed for kinetic transport equations in the diffusive scaling. We first derive an approximate evolution equation for the macroscopic density, from the formal solution of the distribution function, which is then discretized by following characteristics for the transport part with a backward finite difference semi-Lagrangian approach, while the diffusive part is discretized implicitly. After the macroscopic density is available, the distribution function can be efficiently solved even with a fully implicit time discretization, since all discrete velocities are decoupled, resulting in a low-dimensional linear system from spatial discretizations at each discrete velocity. Both first and second order discretizations in space and in time are considered. The resulting schemes can be shown to be asymptotic preserving (AP) in the diffusive limit. Uniformly unconditional stabilities are verified from a Fourier analysis based on eigenvalues of corresponding amplification matrices. Numerical experiments, including high dimensional problems, have demonstrated the corresponding orders of accuracy both in space and in time, uniform stability, AP property, and good performances of our proposed approach.

In popular culture, the stereotypically iconized “geek” can be identified in different media narratives from mainstream television to magazines. Drawing upon insights from sociolinguistics and business communication studies, this paper attempts to identify the discursive constructs of “being geek” in Chinese digital business communication. By collecting the discourse data of online customer reviews from amazon.cn and analyzing the data based on the framework of Critical Discourse Analysis, the study investigates how linguistic mechanisms operate in the shaping of geek culture and the construction of “being geek” in the participatory communication of business. The results revealed lexical variables and generic intertextuality are prominent in the discourse construction of “being geek”, to create a stimulus for a promotional culture in business communication.

Last year, the $\Xi(1620)$ state that is cataloged in the Particle Data Group (PDG) with only one star is reported again in the $\Xi^{-}\pi^{+}$ final state by the Belle Collaboration. Its properties not only the spectroscopy but also the decay width cannot be simply explained in the context of conventional constituent quark models. This intrigues an active discussion on the structure of this resonance. In this work, we study the radiative decays of the newly observed $\Xi(1620)$ assuming that it is a meson-baryon molecular state of $\Lambda\bar{K}$ and $\Sigma\bar{K}$ with spin-parity $J^P=1/2^{-}$ in our previous work. The partial decay widths of the $\Lambda\bar{K}-\Sigma\bar{K}$ molecular state into $\Xi\gamma$ and $\Xi\pi\gamma$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $\Xi(1620)^0\to\gamma\Xi$ and $\Xi(1620)^0\to\gamma\Xi\pi$ are evaluated to be about $118.76-174.21$ KeV and $58.19-68.75$ eV, respectively, which may be accessible for the LHCb. If the $\Xi(1620)$ is $\Lambda\bar{K}-\Sigma\bar{K}$ molecule, the radiative transition strength $\Xi(1620)^0\to\gamma\bar{K}\Lambda$ is quite small and the decay width is of the order of 0.01 eV. Future experimental measurements of these processes can be useful to test the molecule interpretations of the $\Xi(1620)$.

Last year, the $��(1620)$ state that is cataloged in the Particle Data Group (PDG) with only one star is reported again in the $��^{-}��^{+}$ final state by the Belle Collaboration. Its properties not only the spectroscopy but also the decay width cannot be simply explained in the context of conventional constituent quark models. This intrigues an active discussion on the structure of this resonance. In this work, we study the radiative decays of the newly observed $��(1620)$ assuming that it is a meson-baryon molecular state of $��\bar{K}$ and $��\bar{K}$ with spin-parity $J^P=1/2^{-}$ in our previous work. The partial decay widths of the $��\bar{K}-��\bar{K}$ molecular state into $����$ and $������$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $��(1620)^0\to����$ and $��(1620)^0\to������$ are evaluated to be about $118.76-174.21$ KeV and $58.19-68.75$ eV, respectively, which may be accessible for the LHCb. If the $��(1620)$ is $��\bar{K}-��\bar{K}$ molecule, the radiative transition strength $��(1620)^0\to��\bar{K}��$ is quite small and the decay width is of the order of 0.01 eV. Future experimental measurements of these processes can be useful to test the molecule interpretations of the $��(1620)$.

Very recently, three new structures $$\Xi _c(2923)^0$$ Ξ c ( 2923 ) 0 , $$\Xi _c(2938)^0$$ Ξ c ( 2938 ) 0 , and $$\Xi _c(2964)^0$$ Ξ c ( 2964 ) 0 at the invariant mass spectrum of $$\Lambda _c^{+}K^{-}$$ Λ c + K - observed by the LHCb Collaboration trigger a hot discussion about their inner structure. In this work, we study the strong decay mode of the newly observed $$\Xi ^0_c$$ Ξ c 0 assuming that the $$\Xi ^0_c$$ Ξ c 0 is a $$\bar{D}\Lambda -\bar{D}\Sigma $$ D ¯ Λ - D ¯ Σ molecular state. With the possible quantum numbers $$J^p=1/2^{\pm }$$ J p = 1 / 2 ± and $$3/2^{\pm }$$ 3 / 2 ± , the partial decay widths of the $$\bar{D}\Lambda -\bar{D}\Sigma $$ D ¯ Λ - D ¯ Σ molecular state into the $$\Lambda _c^{+}K^{-}$$ Λ c + K - , $$\Sigma _c^{+}K^{-}$$ Σ c + K - ,and $$\Xi _c^{+}\pi ^{-}$$ Ξ c + π - final states through hadronic loop are calculated with the help of the effective Lagrangians. By comparison with the LHCb observation, the current results of total decay width support the $$\Xi _c(2923)^0$$ Ξ c ( 2923 ) 0 as $$\bar{D}\Lambda -\bar{D}\Sigma $$ D ¯ Λ - D ¯ Σ molecule while the decay width of the $$\Xi _c(2938)^0$$ Ξ c ( 2938 ) 0 and $$\Xi _c(2964)^0$$ Ξ c ( 2964 ) 0 can not be well reproduced in the molecular state picture. In addition, the calculated partial decay widths with S wave $$\bar{D}\Lambda -\bar{D}\Sigma $$ D ¯ Λ - D ¯ Σ molecular state picture indicate that allowed decay mode, $$\Xi _c^{+}\pi ^{-}$$ Ξ c + π - , may have the biggest branching ratio for the $$\Xi _c(2923)^0$$ Ξ c ( 2923 ) 0 . The experimental measurements for this strong decay process could be a crucial test for the molecule interpretation of the $$\Xi _c(2923)^0$$ Ξ c ( 2923 ) 0 .

The $\Xi_b(6227)$ baryon with the quantum number $J^P=1/2^{-}$ is considered as a molecular state composed of a $\Sigma_b$ baryon and $\bar{K}$ meson. The partial decay widths of the $\Sigma_b\bar{K}$ molecular state into $\Xi_b\gamma$ and $\Xi_b^{'}\gamma$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $\Xi_b(6227)\to\gamma\Xi_b$ and $\Xi_b(6227)\to\gamma\Xi^{'}_b$ are evaluated to be about 1.50-1.02 KeV and 17.56-24.91 KeV, respectively, which may be accessible for the LHCb. Based on our results we argue that an experimental determination of the radiative decay width of $\Xi_b(6227)$ is important for the understanding of its intrinsic properties.

The $��_b(6227)$ baryon with the quantum number $J^P=1/2^{-}$ is considered as a molecular state composed of a $��_b$ baryon and $\bar{K}$ meson. The partial decay widths of the $��_b\bar{K}$ molecular state into $��_b��$ and $��_b^{'}��$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $��_b(6227)\to����_b$ and $��_b(6227)\to����^{'}_b$ are evaluated to be about 1.50-1.02 KeV and 17.56-24.91 KeV, respectively, which may be accessible for the LHCb. Based on our results we argue that an experimental determination of the radiative decay width of $��_b(6227)$ is important for the understanding of its intrinsic properties.

Very recently, three new structures $��_c(2923)^0$, $��(2938)^0$, and $��(2964)^0$ at the invariant mass spectrum of $��_c^{+}K^{-}$ observed by the LHCb Collaboration triggers a hot discussion about their inner structure. In this work, we study the strong decay mode of the newly observed $��_c$ assuming that the $��_c$ is a $\bar{D}��-\bar{D}��$ molecular state. With the possible quantum numbers $J^p=1/2^{\pm}$ and $3/2^{\pm}$, the partial decay widths of the $\bar{D}��-\bar{D}��$ molecular state into the $��_c^{+}K^{-}$, $��_c^{+}K^{-}$,and $��_c^{+}��^{-}$ final states through hadronic loop are calculated with the help of the effective Lagrangians. By comparison with the LHCb observation, the current results of total decay width support the $��(2923)^0$ as $\bar{D}��-\bar{D}��$ molecule while the decay width of the $��_c(2938)^0$ and $��(2964)^0$ can not be well reproduced in the molecular state picture. In addition, the calculated partial decay widths with $S$ wave $\bar{D}��-\bar{D}��$ molecular state picture indicate that allowed decay modes, $��_c^{+}��^{-}$, may have the biggest branching ratios for the $��_c(2923)$. The experimental measurements for this strong decay process could be a crucial test for the molecule interpretation of the $��_c(2923)$., arXiv admin note: text overlap with arXiv:1002.0218 by other authors

We investigate the possibility of studying the charmed-strange mesons Ds0(2317) and Ds1(2460) by kaon-induced reactions on a proton target in an effective Lagrangian approach. The production process is described by the t-channel D0 and D*0 exchanges, respectively. Our theoretical approach is based on the chiral unitary theory where the Ds0(2317) and Ds1(2460) resonances are dynamically generated. Within the coupling constants of the Ds0(2317) to KD and Ds1(2460) to KD* channels obtained from chiral unitary theory, the total and differential cross sections of the K−p→ΛcDs0(2317) and K−p→ΛcDs1(2460) are evaluated. The K¯p initial state interaction mediated by Pomeron and Reggeon exchanges, which reduces the production cross sections of the Ds0(2317) and Ds1(2460), is also included. If measured in future experiments, the predicted total cross sections and specific features of the angular distributions can be used to test the (molecular) nature of the Ds0(2317) and Ds1(2460).

We investigate the possibility to study the charmed-strange mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ by kaon-induced reactions on a proton target in an effective Lagrangian approach. The production process is described by the $t$-channel $D^{0}$ and $D^{*0}$ exchanges, respectively. Our theoretical approach is based on the chiral unitary theory where the $D_{s0}(2317)$ and $D_{s1}(2460)$ resonances are dynamically generated. Within the coupling constants of the $D_{s0}(2317)$ to $KD$ and $D_{s1}(2460)$ to $KD^{*}$ channels obtained from the chiral unitary theory, the total and differential cross sections of the $K^{-}p\to{}\Lambda_cD_{s0}(2317)$ and $K^{-}p\to{}\Lambda_cD_{s1}(2460)$ are evaluated. The $\bar{K}p$ initial state interaction mediated by Pomeron and Reggeon exchanges is also included, which reduces the production cross sections of the $D_{s0}(2317)$ and $D_{s1}(2460)$. If measured in future experiments, the predicted total cross sections and specific features of the angular distributions can be used to test the (molecular) nature of the $D_{s0}(2317)$ and $D_{s1}(2460)$.

Huangnihe Nature Reserve is located in the northwest of Dunhua City,Yanbian Korean Autonomous Prefecture,Jilin Province.As a provincial level nature reserve,it was built to protect the north temperate mountain forest ecosystems and a variety of rare and endangered wild animals and plants.According to the population and distribution of roe deer(Capreolus capreolus) in Huangnihe Nature Reserve,line transect method was used in the region which roe deer move frequently,i.e.,sample points was selected randomly on the forest map.And then 47 line transects was set along with the vertical direction of the contour.Span is above 1 500 m,length is 3—5 km of the line transect which covered the major vegetation types of protected areas. Because of heavy snow in the high altitudes regions,most of line transects were below 900 m above sea level,only one transect was above 900 m,the highest point of the transect was 943 m,the snow was 86 cm thick.Roe deer lying track was set as the center for a 2 m × 2 m and a 10 m × 10 m quadrats when it was found during the field investigation,and the quadrat center was located with GPS.At the same time,a 2 m × 2 m and 10 m × 10 m quadrats was set every 1000 m of walking as control during the field investigation.If there is a roe deer lying track,then control quadrats statistics will be give up,just for lying track quadrats statistics. Seventy two quadrats used by roe deer and 109 control quadrats were measured during 47 line transect surveys with 179.2 km total length and,the effects of 15 ecological factors,namely elevation,slope direction,gradient,slope location,canopy,thickets coverage,hiding level,food abundance,distance far from human disturbance,diameter at breast height,forest type,conifer,snow depth,fallen tree and bare rock,on winter bed-site selection by roe deer were evaluated in this research totally.Comparing used quadrats with control quadrats through Baileys Confidence Interval Discriminate combining with two-sample Mann-Whitney rank test,the results indicated that significant differences were observed in selection of elevation,slope direction,slope location,canopy,thickets coverage,hiding level,food abundance,forest type,conifer,snow depth and bare rock by roe deer.Roe deer preferred the mixed broadleaf-coniferous forest habitats located in sunny middle slope,average elevation of 591m,lower snow depth,adequate food resources,thickets coverage,canopy density and hiding conditions,especially preferred conifers in mixed forest for rest while avoided habitats with shady slope,typical coniferous forest and bare rocks.Half sunny slope,broad-leaved forest,gradient,distance far from human disturbance and diameter at breast height as well as fallen tree were selected by roe deer randomly.The Binary Logistic Regression demonstrated that food abundance,conifer,snow depth,bare rock and elevation were the dominant factors leading important roles during the process of winter bed-site selection by roe deer,and forest type,slope direction and hiding level were the secondary factors.A Binary Logistic Model could be constructed by these 7 factors as follow: z= 32.628+11.675× slope direction(1)+9.741× slope direction(2)-5.486× forest type(1)-7.933× forest type(2)-7.496× bare rock(1)-9.906× conifer(1)-0.043 ×elevation+0.170×hiding level +0.220×food abundance-0.429×snow depth.The selection probability was that: P(z)= ez/1+ez.The model could predict correctly with 96.1% of overall.