Conformational heterogeneity of molecules physisorbed on a gold surface at room temperature

A quantitative single-molecule tip-enhanced Raman spectroscopy (TERS) study at room temperature remained a challenge due to the rapid structural dynamics of molecules exposed to air. Here, we demonstrate the hyperspectral TERS imaging of single or a few brilliant cresyl blue (BCB) molecules at room temperature, along with quantitative spectral analyses. Robust chemical imaging is enabled by the freeze-frame approach using a thin Al2O3 capping layer, which suppresses spectral diffusions and inhibits chemical reactions and contamination in air. For the molecules resolved spatially in the TERS image, a clear Raman peak variation up to 7.5 cm(-1) is observed, which cannot be found in molecular ensembles. From density functional theory-based quantitative analyses of the varied TERS peaks, we reveal the conformational heterogeneity at the single-molecule level. This work provides a facile way to investigate the single-molecule properties in interacting media, expanding the scope of single-molecule vibrational spectroscopy studies. Tip-enhanced vibrational spectroscopy at room temperature is complicated by molecular conformational dynamics, photobleaching, contaminations, and chemical reactions in air. This study demonstrates that a sub-nm protective layer of Al2O3 provides robust conditions for probing single-molecule conformations

<b>Genome assembly, gene content, and plastic gene expression responses of the Brackishwater Clam (</b><b><i>Corbicula japonica</i></b><b>) from a dynamic estuarine environment</b> Item

Genome assembly, gene content, and plastic gene expression responses of the Brackishwater Clam (Corbicula japonica) from a dynamic estuarine environment</p

A Study on the Safety Evaluation of Escape Routes for Vulnerable Populations in Residential Facilities

The continued increase in human lifespans is accelerating the aging of the population in most countries. The increase in elderly care facilities corresponds to a relative increase in the number of people who are vulnerable in the context of evacuation. For example, an elderly care hospital is a representative facility for vulnerable populations as regards evacuation, as residents in such a hospital cannot evacuate themselves in the event of a fire. It is therefore necessary for such buildings to formulate detailed evacuation plans that consider the walking situations of their residents in the event of a disaster. In this study, the fire dynamics simulator (FDS) was used to calculate the available safety escape time (ASET)&mdash;which is the point at which evacuation is impossible from the ignition time of the fire&mdash;for inpatients in nursing hospitals. The required safety escape time (RSET), which is the time required to move to a safe place, was calculated by reflecting a patient&rsquo;s evacuation speed using Pathfinder. In addition, the evacuation route was simulated with three variables&mdash;stairs, elevators, and ramps&mdash;along with the movement pattern. The simulations of evacuation performance evaluation based on time analysis showed that there were differences in the number of fatalities depending on the choice of evacuation routes and movement patterns for each disabled group. Evacuation using ramps was confirmed to reduce fatalities from at least 48 to up to 60 people compared to evacuation using stairs or elevators. The usage of ramp evacuation in elderly care hospitals has proved to be superior to other evacuation routes in ensuring the safety of vulnerable persons during fire evacuation

Satellite-Based Aerosol Classification for Capital Cities in Asia Using a Random Forest Model

Aerosol types in Asian capital cities were classified using a random forest (RF) satellite-based aerosol classification model during 2018–2020 in an investigation of the contributions of aerosol types, with or without Aerosol Robotic Network (AERONET) observations. In this study, we used the recently developed RF aerosol classification model to detect and classify aerosols into four types: pure dust, dust-dominated aerosols, strongly absorbing aerosols, and non-absorbing aerosols. Aerosol optical and microphysical properties for each aerosol type detected by the RF model were found to be reasonably consistent with those for typical aerosol types. In Asian capital cities, pollution-sourced aerosols, especially non-absorbing aerosols, were found to predominate, although Asian cities also tend to be seasonally affected by natural dust aerosols, particularly in East Asia (March–May) and South Asia (March–August). No specific seasonal effects on aerosol type were detected in Southeast Asia, where there was a predominance of non-absorbing aerosols. The aerosol types detected by the RF model were compared with those identified by other aerosol classification models. This study indicates that the satellite-based RF model may be used as an alternative in the absence of AERONET sites or observations

Balanced optical flow refinement by bidirectional constraint

1

Identification and Phylogenetic Analysis of Chitin Synthase Genes from the Deep-Sea Polychaete <i>Branchipolynoe onnuriensis</i> Genome

Chitin, one of the most abundant biopolymers in nature, is a crucial material that provides sufficient rigidity to the exoskeleton. In addition, chitin is a valuable substance in both the medical and industrial fields. The synthesis of chitin is catalyzed by chitin synthase (CHS) enzymes. Although the chitin synthesis pathway is highly conserved from fungi to invertebrates, CHSs have mostly only been investigated in insects and crustaceans. Especially, little is known about annelids from hydrothermal vents. To understand chitin synthesis from the evolutionary view in a deep-sea environment, we first generated the whole-genome sequencing of the parasitic polychaete Branchipolynoe onnuriensis. We identified seven putative CHS genes (BonCHS1-BonCHS7) by domain searches and phylogenetic analyses. This study showed that most crustaceans have only a single copy or two gene copies, whereas at least two independent gene duplication events occur in B. onnuriensis. This is the first study of CHS obtained from a parasitic species inhabiting a hydrothermal vent and will provide insight into various organisms’ adaptation to the deep-sea hosts

Identification and Phylogenetic Analysis of Chitin Synthase Genes from the Deep-Sea Polychaete Branchipolynoe onnuriensis Genome

Chitin, one of the most abundant biopolymers in nature, is a crucial material that provides sufficient rigidity to the exoskeleton. In addition, chitin is a valuable substance in both the medical and industrial fields. The synthesis of chitin is catalyzed by chitin synthase (CHS) enzymes. Although the chitin synthesis pathway is highly conserved from fungi to invertebrates, CHSs have mostly only been investigated in insects and crustaceans. Especially, little is known about annelids from hydrothermal vents. To understand chitin synthesis from the evolutionary view in a deep-sea environment, we first generated the whole-genome sequencing of the parasitic polychaete Branchipolynoe onnuriensis. We identified seven putative CHS genes (BonCHS1-BonCHS7) by domain searches and phylogenetic analyses. This study showed that most crustaceans have only a single copy or two gene copies, whereas at least two independent gene duplication events occur in B. onnuriensis. This is the first study of CHS obtained from a parasitic species inhabiting a hydrothermal vent and will provide insight into various organisms&rsquo; adaptation to the deep-sea hosts

The complete mitochondrial genome of the sand dollar Astriclypeus mannii (Verrill, 1867) (Echinoidea: Astriclypeidae) in the subtidal sand flat in Jeju Island off the south coast of Korea

We sequenced the complete mitochondrial genome of sand dollar Astriclypeus mannii (Verrill 1867) (Echinoidea: Astriclypeidae) occurring in the subtidal sand flat in Jeju Island off the south coast of Korea. The mitochondrial genome was 15,744 bp in length and contained 13 protein-coding genes (PCGs), 22 transfer RNAs, two ribosomal RNAs, and 140 nucleotides representing the putative control region. We reconstructed the concatenated phylogenetic tree based on 13 PCGs of 18 echinoderms, including A. mannii. From the maximum likelihood clustering, A. mannii was grouped in the order Echinolampadacea. The complete mitochondrial sequence of A. mannii for the first time in this study provide valuable insight in understanding the evolution and phylogenetic analysis of echinoids (sea urchins)

Enhanced Durability and Catalytic Performance of Pt–SnO2/Multi‐Walled Carbon Nanotube with Shifted d‐Band Center for Proton‐Exchange Membrane Fuel Cells

Worldwide, significant efforts are made to identify energy sources that can help achieve carbon neutrality and promote sustainable development. The development of a catalyst that combines durability and high performance is essential for the commercialization of proton‐exchange membrane fuel cells (PEMFCs). In a fuel cell, carbon corrosion occurs during startup and shutdown due to improper local flooding caused by inadequate water management. In this study, a Pt‐based catalyst is designed with excellent durability and high activity. Introducing a metal oxide layer modified with Pt/multi‐walled carbon nanotubes reduces the direct contact between carbon and the fuel cell environment. This helps prevent carbon corrosion and inhibits the separation, aggregation, and growth of Pt nanoparticles. Moreover, the catalyst exhibits enhanced oxygen reduction activity due to the electronic effect of the metal oxide layer that is coated on it. In this study, by implementing a carbon erosion acceleration protocol, excellent catalytic properties during a load‐cycling experiment consisting of 5,000 cycles are reported. The practical application of the developed catalyst in PEMFCs offers an effective approach to developing Pt‐group metal catalysts with exceptional activity