bluuebunny/crossref_metadata_2025 huggingface dataset:
Minimal Embedding Dimensions of Rectangle k-Visibility Graphs
Authors: Slettnes Espen
Published: January 2021

Bar visibility graphs were adopted in the 1980s as a model to represent traces, e.g., on circuit boards and in VLSI chip designs. Two generalizations of bar visibility graphs, rectangle visibility graphs and bar $k$-visibility graphs, were subsequently introduced.

Here, we combine bar $k$- and rectangle visibility graphs to form rectangle $k$-visibility graphs (R$k$VGs), and further generalize these to higher dimensions. A graph is a $d$-dimensional R$k$VG if and only if it can be represented with vertices as disjoint axis-aligned hyperrectangles in $d$-space, such that there is an axis-parallel line of sight between two hyperrectangles that intersects at most $k$ other hyperrectangles if and only if there is an edge between the two corresponding vertices.

For any graph $G$ and a fixed $k$, we prove that given enough spatial dimensions, $G$ has a rectangle $k$-visibility representation, and thus we define the minimal embedding dimension (MED) with $k$-visibility of $G$ to be the smallest $d$ such that $G$ is a $d$-dimensional R$k$VG. We study the properties of MEDs and find upper bounds on the MEDs of various types of graphs. In particular, we find that the $k$-visibility MED of the complete graph on $m$ vertices $K_m$ is at most $\lceil{m/(2(k+1))}\rceil,$ of complete $r$-partite graphs is at most $r+1,$ and of the $m^{\rm th}$ hypercube graph $Q_m$ is at most $\lceil{2m/3}\rceil$ in general, and at most $\lfloor{\sqrt{m}\,}\rceil$ for $k=0,~ m \ne 2.$
Database “Echelon Lists of Kaliningradskaya Oblast Immigrants (1946-1947)”: Architecture, Sources, Data Introduction and the First Results
Authors: Baranova Elena , Maslov Vitalii , Lopatin Mikhail
Published: January 2021

This article considers some aspects related to a database covering migrants from the Russian Federation and the Belorussian Republic to Kaliningradskaya Oblast. The topicality of the study is the poor knowledge bulk related to statistics of such a large-scale migration process initiated by the Soviet Union in the middle of the 20th century which played an important role in the new region formation. It is the first time when an information resource is created that contains data from a large complex of nominative records made along the way with the mass resettlement of new residents of the region by means of train echelons. Besides the description of the source, the most typical types of its documents (echelon lists, acts on arrival and consolidated lists) are considered in detail. The authors discuss the principles to build the database and substantiate the choice in favor of the source-oriented approach. The describe the conceptual structure of the database with reference to some specific features of its logical model and the organization of the graphical user interface. The article describes how a large group of students added limited access data to the database. A preliminary analysis of the database information shows that in 1946 about 2/5 of the arriving people were unable to work (primarily due to their age). The same share, however among the heads of families, was characteristic of single people without a spouse. The absolute majority of household heads were men.
GIS “Spatial Mobility of the Szlachta under Peter the First” in a Prosopographic Study
Authors: Zakharov Andrei Viktorovich , Frolov Alexey
Published: January 2021

The article discusses possibilities of geochronological tracking technology for studying the spatial mobility of social groups in Russia in the past. The GIS proposed is necessary to visualize and analyze spatial data in a prosopographic research of about 400 szlachta representatives in Peter’s Epoch. Spatial mobility is understood as the intensity of person's translocation through settlements and his ability to respond to external challenges by moving. The archival materials of the Senate inspection of the szlachta (1721-1723) served the basis for the study and the resource formation. Particular attention is paid to the design of software research tools – the PostgreSQL database and the web GIS based on the latter. It is the first time when geochronological tracking as a geoinformatics method was used to prosopographically study the Russian nobility. The methods of historical source spatial data representation and visualization are implemented in the form of a geodatabase that is publicly available. Two program modules (the GIS among them) grant a wide range of Internet users an access to historical sources text data as well as synchronically visualized data on the szlachta service under Peter the first.  The authors conclude that it is promising to create a special web interface which provides users with flexible text and geodata filtering and analysis. The web project created can be used both for research in the field of social history, historical geography, genealogy and for educational purposes in such courses as “historical computer science” and “digital humanities”.
Urban Economy of Orlovskaya and Tambovskaya Guberniyas in the Late 18th-Early 19th Centuries (General Land Survey Data)
Authors: Chernenko Dmitrii Anatol'evich
Published: January 2021

The article poses a problem of a multi-style character of the urban economy in Russia in the late 18th - early 19th centuries and its reflection in the General Land Survey taken in European Russia at that period. These are the Economic Comments to the General Land Survey which recorded the main parameters of the urban economy within the framework of the unified description program that provide for comparing its agrarian, commercial and industrial components. The study uses the materials of the Economic Comments on 26 cities of two Black Earth Region Guberniyas of Russia – Orlovskaya and Tambovskaya ones. The specificity of the region is determined by its relatively late development and the formation of the urban network within the framework of large defensive projects of the Moscow state. Statistical analysis and GIS-mapping of the Comments data allowed one to come to the following conclusions. This region is commonly characterized by the formation of large agricultural complexes with large (more than 5 thousand desyatins) areas of arable and hay fields surrounding the cities during the General Land Survey. This circumstance significantly increased the area of the city within the framework of the "general urban boundary", but to a much lesser extent influenced the total size of its population. The industry of the cities of the region consisted almost exclusively of small "plants" while big manufacturing production was at its early stage of development and was not dependent on the processes of concentration of small enterprises in individual cities. The function of the cities of the region as centers of trade was much more pronounced. Fairs and/ or weekly auctions were held in most of them. The results of the Economic Comments statistics correlation analysis allow one to assume that further development of the Black Earth Region cities was mainly related to commercial and industrial branches of their economy.
Virtual Reality Technologies and Universal 3D Reconstruction Interface Development
Authors: Mironenko Maxim , Chertopolokhov Viktor , Belousova Margarita
Published: January 2021

The article summarizes the results of a two-year study of the issues related to the virtual reality and augmented reality technologies use to virtually reconstruct Moscow Bely Gorod in the 16th-18th centuries. The authors describe mathematical methods, software and hardware which grant access to the historical reconstruction of historical urban landscapes. An important feature of the reconstruction is the source verification module which was used to construct three-dimensional models of the landscape, buildings and the general scenery. The article names the basic principles which the verification module and its interface are based on and considers some optimum problems solved when constructing the interface. The project uses a hybrid motion tracking system as a combination of optical and inertial data. The archival sources used in the reconstruction process are presented in the virtual environment by means of a 3D graphical user interface for the virtual reality. The information displayed is generated from the database of historical sources which includes information about the urban development and individual buildings of Bely Gorod, their parts, location, purpose, owners and construction date. The database contains both text and graphic historical sources. The results obtained also include new algorithms, software and hardware systems as well as the experiment results. 
Diverse viral proteases activate the NLRP1 inflammasome
Authors: Tsu Brian V , Beierschmitt Christopher , Ryan Andrew P , Agarwal Rimjhim , Mitchell Patrick S , Daugherty Matthew D
Published: January 2021

The NLRP1 inflammasome is a multiprotein complex that is a potent activator of inflammation. Mouse NLRP1B can be activated through proteolytic cleavage by the bacterial Lethal Toxin (LeTx) protease, resulting in degradation of the N-terminal domains of NLRP1B and liberation of the bioactive C-terminal domain, which includes the caspase activation and recruitment domain (CARD). However, natural pathogen-derived effectors that can activate human NLRP1 have remained unknown. Here, we use an evolutionary model to identify several proteases from diverse picornaviruses that cleave human NLRP1 within a rapidly evolving region of the protein, leading to host-specific and virus-specific activation of the NLRP1 inflammasome. Our work demonstrates that NLRP1 acts as a 'tripwire' to recognize the enzymatic function of a wide range of viral proteases and suggests that host mimicry of viral polyprotein cleavage sites can be an evolutionary strategy to activate a robust inflammatory immune response.
Strategies for recovery of imbalanced full-scale biogas reactor feeding with palm oil mill effluent
Authors: Wongfaed Nantharat , Kongjan Prawit , Suksong Wantanasak , Prasertsan Poonsuk , O-Thong Sompong
Published: January 2021

Background

Full-scale biogas production from palm oil mill effluent (POME) was inhibited by low pH and highly volatile fatty acid (VFA) accumulation. Three strategies were investigated for recovering the anaerobic digestion (AD) imbalance on biogas production, namely the dilution method (tap water vs. biogas effluent), pH adjustment method (NaOH, NaHCO3, Ca(OH)2, oil palm ash), and bioaugmentation (active methane-producing sludge) method. The highly economical and feasible method was selected and validated in a full-scale application.

Results

The inhibited sludge from a full-scale biogas reactor could be recovered within 30–36 days by employing various strategies. Dilution of the inhibited sludge with biogas effluent at a ratio of 8:2, pH adjustment with 0.14% w/v NaOH, and 8.0% w/v oil palm ash were considered to be more economically feasible than other strategies tested (dilution with tap water, or pH adjustment with 0.50% w/v Ca(OH)2, or 1.25% NaHCO3 and bioaugmentation) with a recovery time of 30–36 days. The recovered biogas reactor exhibited a 35–83% higher methane yield than self-recovery, with a significantly increased hydrolysis constant (kH) and specific methanogenic activity (SMA). The population of Clostridium sp., Bacillus sp., and Methanosarcina sp. increased in the recovered sludge. The imbalanced full-scale hybrid cover lagoon reactor was recovered within 15 days by dilution with biogas effluent at a ratio of 8:2 and a better result than the lab-scale test (36 days).

Conclusion

Dilution of the inhibited sludge with biogas effluent could recover the imbalance of the full-scale POME-biogas reactor with economically feasible and high biogas production performance.
Biochemical Studies on edible oysters Crassostrea madrasensis and Saccostrea cucullata.
Authors: Paul Packiam , Stella Chelladurai , Siva J
Published: January 2021

In general, changes in biochemical components are closely linked to the state of sexual maturity of the mollusks and to energy supply, either directly from ingested food or from previously stored reserves. Carbohydrates are considered to be the main energy source in adult marine bivalves and are important for gamete formation and maintenance of adult condition during periods of nutritive stress or in winter. Many studies have related changes in the biochemical composition of bivalves with the reproductive cycle mostly in the natural environment. Energy storage and biochemical cycle are closely related to reproductive activity in marine bivalves. The present study indicates that major biochemical constituents in oyster Crassostrea madrasensis and Saccostrea cucullate are significantly influenced by environment condition such as quantity of food availability, temperature and salinity. The high contents of lipids, proteins, carbohydrates, and water content values, during summer are indicating this season as the best for harvesting this particular oyster species and the statistical analysis of the biochemical composition of the tissue sample of the oyster revealed positive correlation in both species of oyster Crassostrea madrasensis and Saccostrea cucullata. The strong Positive Correlation were observed in between the two stations and the highest value of protein, carbohydrate and lipids were observed in Crassostrea madrasensis rock and creek when it compare to Saccostrea cucullata.Keywords: Protein, Carbohydrate, Lipid , Crassostrea madrasensis, Saccostrea cucullata, oysters