Bottom Attenuation Coefficient Inversion Based on the Modal Phase Difference Between Pressure and Vertical Velocity from a Single Vector Sensor

An inversion scheme based on time-warping is presented for estimating the attenuation coefficient of a sediment bottom using a single vector sensor, restricted to shallow water and using low-frequency impulsive sources. The attenuation information is extracted from the modal phase difference between pressure and vertical velocity. The method is derived from Pekeris waveguide theoretical equations and the eigen values are obtained using the normal mode model Kraken. Some changes are made to the time-warping process to mitigate the inherent interference between adjacent modes, which improves the phase extraction capabilities. Results are presented for a two-layer, homogeneous environment using the RAM propagation model for depth-dependent sound speed profile simulations. This version of RAM was updated to provide radial and vertical velocities. For additional generality, the technique is evaluated in the presence of white noise.

Microbial communities network structure across strong environmental gradients: How do they compare to macroorganisms?

The way strong environmental gradients shape multispecific assemblages has allowed us to examine a suite of ecological and evolutionary hypotheses about structure, regulation, and community responses to fluctuating environments. But whether the highly diverse co-occurring, free-living microorganisms are shaped in similar ways as macroscopic organisms, across the same gradients, has yet to be addressed in most ecosystems. The everything is everywhere hypothesis suggests they are not, at least not to the same extent. Here we characterize the structure of intertidal microbial biofilm communities and compare the intensity of zonation at the species-level, changes in taxonomic diversity and composition at the community level, and network attributes, with those observed in co-occurring macroalgae and invertebrates. At the level of species and OTUs, for dominant macro and microorganisms respectively, microbes showed less variability across the tidal gradient than macroorganisms. At the community-level, however, microbes and macro-organisms showed similarly strong patterns of tidal zonation, with major changes in composition and relative abundances across tides. Moreover, the proportion of environmental specialists in different tidal zones was remarkably similar in micro and macroscopic communities, and taxonomic richness and diversity followed similar trends, with lower values in the high intertidal zone. Network analyses showed similar connectivity and transitivity, despite the large differences in absolute richness between the groups. A high proportion of positive co-occurrences within all tidal zones and mostly negative links between the high and low tidal zones were observed among habitat specialist taxa of micro-and macro-organisms. Thus, our results provide partial support to the idea that microbes are less affected by environmental variability than macroscopic counterparts. At the species-level, the most common microbe species exhibit less variation across tides than most common macroscopic organisms, suggesting the former perceive a more homogeneous environment and/or are more resistant to the associated stress. At the community-level, most indicators of community and network structure across the gradient are similar between microbes and macro-organisms, suggesting that despite orders of magnitude differences in richness and size, these two systems respond to stress gradients, giving rise to zonation patterns.

Leaf Nutrient Relations of Cycads in a Common Garden

Background and Aims Research required to clarify leaf nutrient relations of cycad species has been inadequate. Common garden studies are useful for determining the influence of genetics on leaf traits because of the homogeneous environment among experimental units. To date, there have been no common garden studies which included all ten genera of cycads. The full phylogenetic breadth has, therefore, not been included in this important area of study. Methods We examined macronutrient and micronutrient content of leaves from one representative species from each of the ten cycad genera at Nong Nooch Tropical Botanical Garden in Thailand. Nitrogen content was determined by dry combustion, and the remaining nutrients were quantified by spectrometry. Results The least variable elements were nitrogen and phosphorus, and the most variable elements were boron and sodium. Nutrient content based on leaflet area was more variable than based on leaflet mass, reflecting species differences in specific leaf area. There were no universal macronutrient or micronutrient signals indicating clear phylogenetic distinctions. Implications for Conservation: Active management of threatened cycad taxa requires research to develop the knowledge to enable evidence-based decisions. This common garden study inclusive of all 10 cycad genera creates a foundation to determine leaf nutrient sufficiency ranges to inform management decisions.

Analysis on a diffusive SEI epidemic model with/without immigration of infected hosts

<p style='text-indent:20px;'>In this paper, we study a reaction-diffusion SEI epidemic model with/without immigration of infected hosts. Our results show that if there is no immigration for the infected (exposed) individuals, the model admits a threshold behaviour in terms of the basic reproduction number, and if the system includes the immigration, the disease always persists. In each case, we explore the global attractivity of the equilibrium via Lyapunov functions in the case of spatially homogeneous environment, and investigate the asymptotic behavior of the endemic equilibrium (when it exists) with respect to the small migration rate of the susceptible, exposed or infected population in the case of spatially heterogeneous environment. Our results suggest that the strategy of controlling the migration rate of population can not eradicate the disease, and the disease transmission risk will be underestimated if the immigration of infected hosts is ignored.</p>

Project team acquiring based on digital footprint

Project management issues are closely related to a team acquiring. Traditionally considered factors are the level of experience, interest level, personal qualification, availability, and knowledge - do not take into account the interaction of team members. In this regard, the increased conflictogenic situation may complicates communication in the project and reduces its effectiveness. The proposed methodology analyzes the digital footprint of candidates who are the potential project team members in an intracorporate messenger. The analyzed elements are words nominating emotions, words describing emotions and emotive means (emoji, punctuation marks, Caps Lock symbols). Based on the analysis of the digital footprint, the diagnostics of the expected and avoidable characteristics of team members is carried out, a homogeneous environment is formed based on the median indicators. Selected project team members must correspond to discovered indicators or have minimal deviations. This technique can also be adapted for recruiting members into an already established team. Diagnostics must be done in a similar way, the group-specific characteristic must be identified, and suitable candidates should not deviate from the median value by more than 1 point. Thus, there is no model of an “ideal” team, since it is formed in the format of an ideal combination of existing members.

Political Theology of International Law: Methodological Facets and Borders

The article investigates the possibility of applying political theology as a specific methodological approach to international law. As the key theses of political theology were originally formulated by C. Schmitt in the context of national law acting in a homogeneous environment, political theology discourse in the modern philosophy of international law is mainly related to the universalist projects of global law based on an analogy with national law. The first of such strategies, the expansionist strategy, presupposes the construction of global order by the world hegemon. The second, the cosmopolitan strategy, assumes that international law can be built on the basis of an ongoing process of discussion of the global order foundations by the widest possible range of actors. Both of these strategies charm “eternal peace” and are nourished by a common messianic spirit and, therefore, are utopian. However, Schmitt’s international law legacy offers an atypical non-universalist and anti-messianic view on international law as a heterogeneous global legal order based on spatial concepts. Despite the fact that the application of political theology to this kind of order is difficult, it shall not be excluded for several reasons. The pluralistic structure of the heterogeneous order can be seen as a katechon that holds back the end of history. Finally, the political theology of international law can be applied to analyze the historical transformations of the international legal order.