Heterogeneous popularity of metabolic reactions from evolution

The composition of cellular metabolism is different across species. Empirical data reveal that bacterial species contain similar numbers of metabolic reactions but that the cross-species popularity of reactions is so heterogenous that some reactions are found in all the species while others are in just few species, characterized by a power-law distribution with the exponent one. Introducing an evolutionary model concretizing the stochastic recruitment of chemical reactions into the metabolism of different species at different times and their inheritance to descendants, we demonstrate that the exponential growth of the number of species containing a reaction and the saturated recruitment rate of brand-new reactions lead to the empirically identified power-law popularity distribution. Furthermore, the structural characteristics of metabolic networks and the species' phylogeny in our simulations agree well with empirical observations.Comment: Main: 5 pages, 4 figures, Supplemental Material: 4 pages, 6 figure

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Amyotrophic lateral sclerosis (ALS) is a progressively paralytic neurodegenerative disease that can be caused by mutations in Cu/Zn-superoxide dismutase 1 (SOD1). Transgenic mice that overexpress mutant SOD1 develop paralysis and accumulate aggregates of mutant protein in the brainstem and spinal cord. Bee venom (BV), which is also known as apitoxin, is extracted from honeybees and is commonly used in oriental medicine for the treatment of chronic rheumatoid arthritis and osteoarthritis. The purpose of the present study was to determine whether BV affects misfolded protein aggregates such as alpha-synuclein, which is a known pathological marker in Parkinson disease, and ubiquitin-proteasomal activity in hSOD1G93A mutant mice. BV was bilaterally administered into a 98-day-old hSOD1G93A animal model. We found that BV-treated hSOD1G93A transgenic mice showed reduced detergent-insoluble polymerization and phosphorylation of α-synuclein. Furthermore, phosphorylated or nitrated α-synuclein was significantly reduced in the spinal cords and brainstems of BV-treated hSOD1G93A mice and reduced proteasomal activity was revealed in the brainstems of BV-treated symptomatic hSOD1G93A. From these findings, we suggest that BV treatment attenuates the dysfunction of the ubiquitin-proteasomal system in a symptomatic hSOD1G93A ALS model and may help to slow motor neuron loss caused by misfolded protein aggregates in ALS models

Correlation-enhanced viable core in metabolic networks

Cellular ingredient concentrations can be stabilized by adjusting generation and consumption rates through multiple pathways. To explore the portion of cellular metabolism equipped with multiple pathways, we categorize individual metabolic reactions and compounds as viable or inviable: A compound is viable if processed by two or more reactions, and a reaction is viable if all of its substrates and products are viable. Using this classification, we identify the maximal subnetwork of viable nodes, referred to as the {\it viable core}, in bipartite metabolic networks across thousands of species. The obtained viable cores are remarkably larger than those in degree-preserving randomized networks, while their broad degree distributions commonly enable the viable cores to shrink gradually as reaction nodes are deleted. We demonstrate that the positive degree-degree correlations of the empirical networks may underlie the enlarged viable cores compared to the randomized networks. By investigating the relation between degree and cross-species frequency of metabolic compounds and reactions, we elucidate the evolutionary origin of the correlations.Comment: 8 pages, 4 figure

An Analysis on Size Suitability of Protective Masks

Since a mask which is not suitable for a human face type has a low protection effect, it is necessary to design the shape of the mask reflecting the face shape of the human body in consideration of the size and shape of each part of the face. The masks analyzed in this study are classified into a yellow dust mask(sanitation mask) and a Fine dust protective mask sold in four countries of Korea, China, the US and England. The standard of Korea is KF(Korea Filter, particle blocking function), which is divided into KF80, KF94 and KF99, which are certified by Ministry of Food and Drug Safety. The standard of the US is N95 that is certified by the National Institute for Occupational Safety and Health (NIOSH). The result ofanalyzing the sizes of products is as follows. First, there was a significant difference among the products in the 3 horizontal length items of Nose-Tragion A, Lip-Tragion A, Menton-Tragion B and the 1 vertical length item of chin-menton length. The Nose-Tragion A was the U.S. 12.2cm \u3e England 10.8cm \u3e China 10.7cm \u3e Korea 9.6cm. The result of analyzing fine dust masks in the market showed that they mark the structures, forms and penetration ratio of fine dust, but there is no size standard for each size. Therefore, it is necessary to establish standards of each size for suitable pattern designs for face shapes in each country

Driving factors of carbon emissions from household energy combustion in China

Reducing carbon emissions resulting from household direct energy combustion while ensuring equal access to energy is essential for fair transition towards carbon neutrality. In this regard, understanding the driving factors of household direct carbon emissions and projecting future emission pathways are necessary for effective policy implementation. In this study, we applied the logarithmic mean Divisia index model to investigate changes in household direct carbon emissions from 2000 to 2021, and established six scenarios to assess the impacts of energy efficiency improvement and energy transition on carbon reduction. The results showed that the growing household expenditure continuously drives the increase in direct carbon emissions, while the decline in the energy demand per unit household expenditure and energy transition drives the decrease in carbon emissions. Replacing direct energy combustion with electricity is vital to reduce household direct emissions. This study highlights the importance of improving the energy efficiency and promoting the electrification of household energy consumption. Policy interventions should be implemented to facilitate behavioural changes, technology development, and low-carbon infrastructure construction

Examining Commuting Times and Jobs-housing Imbalance in Seoul: An Empirical Analysis of Urban Spatial Structure

Public transportation policy plays a significant role in facilitating ridership as well as travel modes, economic activities, and environmental aspects. Seoul has experienced rapid urbanization. Also, high density developments and uncontrolled land use gave rise to extensive urban sprawl in the Seoul Metropolitan Areas (SMA). Due to increased use of private vehicles, which created serious traffic congestion, the Seoul Metropolitan Government (SMG) has reformed public transportation policies-introduced bus transportation reform (BTR) in 2004 and reformed fare and ticketing structures in 2009. This research focuses on the relationships between socioeconomic characteristics and commuting patterns by applying smart card data that includes individual travel behaviors during commuting periods. Among regression results, average commuting times are significantly associated with the proportion of population with lower levels of education and the number of public transit stations. These results appear to support the idea that the lower educated people in each district tend to have longer commuting times. Also, the greater availability of public transit stations contributes to shorter commuting times. Finally, analyzing commuting times seems to be important for determining demographic movement as well as locational advantages in certain regions of Seoul based on public transportation policies

MnBa2(HPO4)2(H2PO4)2

Crystals of manganese(II) dibarium bis­(hydrogenphosphate) bis­(dihydrogenphosphate), MnBa2(HPO4)2(H2PO4)2, were obtained by hydro­thermal synthesis. The title compound is isotypic with its CdII and CaII analogues. The structure is built up of an infinite {[Mn(HPO4)2(H2PO4)2]4−}n chain running along [100], which consists of alternate MnO6 octa­hedra and [PO4] tetra­hedra, in which the centrosymmetric MnO6 octa­hedra share their four equatorial O-atom corners with tetra­hedral [PO3(OH)] groups and their two axial apices with tetra­hedral [PO2(OH)2] groups. These chains are held together by BaO9 coordination polyhedra, developing into a three-dimensional structure. The O—H⋯O hydrogen bonds additionally stabilize the structural set-up. Due to the ionic radius of Mn2+ being much smaller than those of Ca2+ and Cd2+, this may imply that their adopted structure type has a great tolerance for incorporating various ions and the exploitation of more diverse compounds in the future is encouraged

Melittin restores proteasome function in an animal model of ALS

Amyotrophic lateral sclerosis (ALS) is a paralyzing disorder characterized by the progressive degeneration and death of motor neurons and occurs both as a sporadic and familial disease. Mutant SOD1 (mtSOD1) in motor neurons induces vulnerability to the disease through protein misfolding, mitochondrial dysfunction, oxidative damage, cytoskeletal abnormalities, defective axonal transport- and growth factor signaling, excitotoxicity, and neuro-inflammation