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The deposition of ultrafine aerosols with a size range of 3–20 nm in a needle charger has been studied numerically by simulating the flow field and the particle trajectory. The calculation model explored the particle deposition in the needle charger without applied voltage for various particle diameters, flow rates, entrance radial positions and deposition axial distances. It is first quantitatively proposed that most of the particles are attached to the outer electrode wall instead of the needle electrode wall for different flow rates and particle diameters. It is found that the numerical results of the particle deposition of the needle charger are consistent with previous experimental data. Moreover, the results demonstrate that reducing the flow rate increases the particle deposition of the needle charger. The numerical models explain and quantify the particle deposition and its attachment position for the needle charger without applied voltage.

This work focuses on the concentration and health effects of volatile organic compounds (VOCs) at an intercity bus terminal in Taipei City, Taiwan. In this study, 36 VOCs were detected in the bus terminal, including 19 hazardous air pollutants. The measurement results indicate that ethanol, acetone, toluene, and methyl tert-butyl ether (MTBE) were the main VOCs dominating this bus terminal. Moreover, the average concentration of benzene, toluene, ethylbenzene, and xylene (BTEX) compounds was 106.0 μg/m3 inside the bus terminal, contributing to approximately 70% of the hazardous air pollutants. The measurement results suggest that traffic emissions, especially from diesel buses, were the major pollution sources in the bus terminal. The cancer risk for 1,3-butadiene, benzene, ethylbenzene, and naphthalene exceeded the suggested value by the U.S. EPA. In addition, the individual chronic hazard quotient of benzene was higher than the recommended level. The findings of this work imply that bus terminal workers face a potential health risk, which is a matter of concern.

Highway vehicle emissions can result in adverse health problems to nearby residents and workers, especially during traffic congestion. In response, the policy to implement electronic toll collection (ETC) has helped alleviate traffic congestion, as compared to manual toll collection (MTC) and has led to reduced air pollution and improved public health. However, the effect of ETC in reducing particulate matter polluting the air is not well understood, especially in the ultrafine particle (UFP) range (particle diameter100 nm). To the best of our knowledge, this is the first study to investigate how ETC affects the traffic pattern and air quality, especially UFP and PM

Proximity labeling (PL) and chemical cross-linking (XL) mass spectrometry are two powerful methods to dissect protein-protein interactions (PPIs) in cells. Although PL typically captures neighboring proteins within a range of 10-20 nm of a single bait protein, chemical XL defines direct protein-protein contacts within 1 nm in a systemic manner. Here, we develop a new method, named PL/XL-MS, to harness the advantages of both PL and XL. PL/XL-MS can enrich a subcellular compartment by PL and simultaneously identify PPIs of multiple proteins from XL data. We applied PL/XL-MS to dissect the human nuclear envelope interactome. PL/XL-MS successfully enriched the nuclear envelope proteins and identified most known inner nuclear membrane proteins. By searching the cross-linked peptides, we successfully observed 109 literature-curated PPIs of 14 nuclear envelope proteins. Based on the homoprotein XL data, we experimentally characterized a nuclear matrix protein, Matrin-3, and observed its preferential localization near the nuclear envelope. PL/XL-MS is a simple and general method for studying protein networks in a subproteome of interest.

Green recycled building materials (GRBMs) have potential to reduce carbon footprint but with insufficient emission information. The increasing application of GRBMs may affect human health due to potential primary and/or secondary emissions. This study center on the assessment of carbonyls emissions and ozone removal on Green Recycled Building Materials under ozone exposure circumstances. Tested materials include gypsum board (GB), waterproof gypsum board (WGB), fiber cement board (FCB), and calcium silicate board (CSB). Among all the observed carbonyls, methacrolein and formaldehyde were the only two that could be found on all four recycled building materials. All carbonyls compounds had relatively high emission factors at the beginning of the experiment and decreased to a relatively lower level one month later. Carbonyls emissions were about 33.3%、27.0%、59.2% and 7.0% of their original values for WGB, FCB, CSB, and GB, respectively. The ozone removal efficiencies at the beginning and one month later were 63.26±6.11% and 61.59±5.46% on CSB, 55.74±4.94% and 47.16±7.97% on FCB, 54.59±6.50% and 34.93±6.77% on GB, and 53.63±8.40% and 23.49±6.63% on WGB, respectively. CSB seems to be a healthier recycled building material compared with WGB, GB and FCB in terms of low carbonyls emissions and high ozone removal efficiency.

This paper presents an inline transition between microstrip line and rectangular waveguide using a ridge structure. The simulation shows an insertion loss less than 3.6 dB and a return loss better than 10 dB from 285 to 315 GHz.

Air quality inside metro systems is a critical issue for commuters and metro employees because of the considerable time they spend traveling or working in such systems. This study measured the PM10, PM2.5, particle number (PN), and CO2 levels and particle mass size distributions inside operating trains to reveal the factors influencing the concentrations and size distributions of particulate matter (PM) inside metro train carriages traveling in different environments. The measurement results demonstrated that the CO2 level was associated with ridership and that the PM levels and particle mass size distributions were highly affected by the immediate surroundings of the train, such as whether it was journeying through underground tunnels or on ground-level tracks as well as its direction of travel. Furthermore, the particle mass size distributions inside the metro train carriages exhibited a clear triple-mode pattern, whereas those for the ground-level and underground routes differed considerably due to different particle sources.

Nonequilibrium hidden states, both transient and long-lived, provide a unique window into thermally inaccessible regimes of strong coupling between microscopic degrees of freedom in quantum materials. Understanding the physical origin of these states is of both fundamental and practical significance, allowing the exploration of far-from-equilibrium thermodynamics and the development of optoelectronic devices with on-demand photoresponses. However, mapping the ultrafast formation of a long-lived hidden phase remains a long-standing challenge in physics since the initial state of the system is not recovered rapidly and conventional pump-probe methods are thus not applicable. Here, using a suite of state-of-the-art single-shot spectroscopy techniques, we present a direct ultrafast visualization of the photoinduced phase transition to both transient and long-lived hidden states in an electronic crystal, 1T-TaS2. Capturing the dynamics of this complex phase transformation in a single-shot fashion demonstrates a commonality in microscopic pathways, driven by the collapse of charge order, that the system undergoes to enter the hidden state and provides unambiguous spectral fingerprints that distinguish such state from thermally accessible phases. We present a theory of fluctuation-dominated process that explains both the dynamics and the nature of the metastable state. Our results settle the debate around the origin of this elusive metastable state and pave the way for the discovery of new quantum phases of matter.

Cancer cells have dramatically increased demands for energy as well as biosynthetic precursors to fuel their restless growth. Enhanced glutaminolysis is a hallmark of cancer metabolism which fulfills these needs. Two glutamine transporters, SLC1A5 and SLC38A2, have been previously reported to promote glutaminolysis in cancer with controversial perspectives. In this study, we harnessed the proximity labeling reaction to map the protein interactome using mass spectrometry-based proteomics and discovered a potential protein-protein interaction between SLC1A5 and SLC38A2. The SLC1A5/SLC38A2 interaction was further confirmed by bimolecular fluorescence complementation assay. We further investigated the metabolic influence of SLC1A5 and SLC38A2 overexpression in human cells, respectively, and found that only SLC38A2, but not SLC1A5, resulted in a cancer-like metabolic profile, where the intracellular concentrations of essential amino acids and lactate were significantly increased as quantified by nuclear magnetic resonance spectroscopy. Finally, we analyzed the 5-year survival rates in a large pan-cancer cohort and found that the SLC1A5hi /SLC38A2lo group did not relate to a poor survival rate, whereas the SLC1A5lo /SLC38A2hi group significantly aggravated the lethality. Intriguingly, the SLC1A5hi /SLC38A2hi group resulted in an even worse prognosis, suggesting a cooperative effect between SLC1A5 and SCL38A2. Our data suggest that SLC38A2 plays a dominant role in reprogramming the cancer-like metabolism and promoting the cancer progression, whereas SLC1A5 may augment this effect when co-overexpressed with SLC38A2. We propose a model to explain the relationship between SLC1A5, SLC38A2 and SCL7A5, and discuss their impact on glutaminolysis and mTOR signaling.

Environmental friendly building materials (BMs) get more attention due to their potential to reduce carbon and air pollutant emissions. However, recycled building materials (RBMs) have no required standard of volatile organic compounds (VOCs) emissions. This study was mainly about the assessment of benzene, toluene, ethylbenzene, and xylene (BTEX), as well as carbonyls emissions from recycled building materials, including gypsum board (GB), calcium silicate board (CSB), fiber cement board (FCB), class I built wall tile (WT), and waterproof gypsum board (WGB). The highest initial and final levels of BTEX were observed on CSB, followed by GB and FCB, and no detectable BTEX were observed on WT and WGB. Benzene was with the highest level among all identified BTEX. Emissions of carbonyls were observed on all materials. The highest initial and final levels of carbonyls were observed on GB, followed by FCB and CSB, while the lowest ones were detected on WT and WGB. The final (96-h) steady-state emissions of BTEX from GB and CSB were 9 and 37 times those from conventional pairs and 27 and 41 times those from low-VOC pairs. Similarly, the final steady-state emissions of carbonyls from GB and CSB were 4.8 and 1.3 times those from conventional pairs and 16 and 2.5 times those from low-VOC pairs. The requirement of evaluation standard for VOC emissions from RBMs is highly recommended to protect consumers. Graphical abstract.

The temperature-dependent recombination of caged-contact pairs following triiodide photolysis is investigated via ultrafast single-shot pump-probe spectroscopy. We find that the fraction of contact pairs formed increases at low temperature while the decays obey an Arrhenius relation.

Biomass burning episodes are critical particulate matter (PM) issues in Taiwan. The occurrence patterns of biomass burning events through long-term PM monitoring are worth further exploration. This study monitored PM10, PM2.5, and black carbon (BC) over one year in central Taiwan. The source apportionment of BC was examined using light absorption techniques and divided into fossil fuel combustion (BCf) and biomass burning (BCb). The monitoring results showed that the annual average PM10, PM2.5, and BC mass concentrations were 45.4 μg/m3, 19.8 μg/m3, and 0.79 μg/m3, respectively, while the annual average ratio of BC/PM2.5 was 0.044. Furthermore, BCf was remarkably higher than BCb, accounting for 89% of the total BC mass. However, it was noticed that biomass burning smoke impacted the air quality by enhancing PM10, PM2.5, and BCb over monitoring location. There were 14.4% of hourly PM10 events (≥125 μg/m3) and 10.0% of hourly PM2.5 events (≥35 μg/m3) resulting from biomass burning episodes at this monitoring site in one-year observation. The hourly average PM10 and PM2.5 concentrations during these biomass burning episodes were 2.1 and 2.3 times higher than the annual average PM10 and PM2.5 concentrations. During severe biomass burning episodes, high levels of human carcinogens, such as 1, 3-butadiene, benzene, and isoprene were also observed. The results demonstrate that air quality is severely degraded during biomass burning episodes. Therefore, further research is required to understand the effects of biomass burning events on the residents' acute and chronic health conditions.

In this study, indoor PM concentrations and size distributions were measured at different time periods to identify the sources of indoor PM in an office building. The measurement results indicate that indoor PM concentration was affected by outdoor air quality conditions, building ventilation system operations, and indoor activities. The results demonstrated that the indoor PM 10 concentration was significantly affected by the outdoor air quality conditions when the ventilation system was turned on. However, the outdoor and indoor PM 10 concentrations were less correlated when the ventilation system was turned off. Moreover, fine PM was the major component of the indoor PM in the air supply device. Additionally, the indoor particle mass size distributions exhibited a triple-mode pattern on working days. The dominant mode was at approximately 0.33 μm, and the other two modes were at 2–4 μm and 12–14 μm. Specifically, an extremely coarse mode at 12–14 μm could be observed during working hours, demonstrating that these coarse particles in the indoor environment were caused by indoor activities during working hours. Moreover, the indoor particle mass size distributions on the holidays exhibited a stable double-mode pattern, suggesting that the coarse particles in the indoor air completely vanished due to sedimentation because of less indoor activities on the holidays.

MicroRNAs (miRNAs) are small non-coding RNAs (typically consisting of 18–25 nucleotides) that negatively control expression of target genes at the post-transcriptional level. Owing to the biological significance of miRNAs, miRTarBase was developed to provide comprehensive information on experimentally validated miRNA–target interactions (MTIs). To date, the database has accumulated >13,404 validated MTIs from 11,021 articles from manual curations. In this update, a text-mining system was incorporated to enhance the recognition of MTI-related articles by adopting a scoring system. In addition, a variety of biological databases were integrated to provide information on the regulatory network of miRNAs and its expression in blood. Not only targets of miRNAs but also regulators of miRNAs are provided to users for investigating the up- and downstream regulations of miRNAs. Moreover, the number of MTIs with high-throughput experimental evidence increased remarkably (validated by CLIP-seq technology). In conclusion, these improvements promote the miRTarBase as one of the most comprehensively annotated and experimentally validated miRNA–target interaction databases. The updated version of miRTarBase is now available at http://miRTarBase.cuhk.edu.cn/.

Transition metal oxides possess complex free energy surfaces with competing degrees of freedom. Photoexcitation allows shaping of such rich energy landscapes. In epitaxially strained $\mathrm{La_{0.67}Ca_{0.33}MnO_3}$, optical excitation with a sub-100 fs pulse above $2\ \mathrm{mJ/cm^2}$ leads to a persistent metallic phase below 100 K. Using single-shot optical and terahertz spectroscopy, we show that this phase transition is a multi-step process. We conclude that the phase transition is driven by partial charge order melting, followed by growth of the persistent metallic phase on longer timescales. A time-dependent Ginzburg-Landau model can describe the fast dynamics of the reflectivity, followed by longer timescale in-growth of the metallic phase., 5 pages plus 7 pages supplement, 4 figures plus 2 figures supplement

The Yanshui Beehive Firework Festival is a traditional folk activity in Southern Taiwan held during the Lantern Festival, and it is the third largest folk celebration in the world. During this festival, more than 200 firecracker towers with hundreds of thousands of firecrackers are ignited, posing a risk to public health because of an abrupt increase in particulate matter concentrations within a short period. In this study, real-time variations of PM2.5 (particles with an aerodynamic diameter less than or equal to 2.5 µm), black carbon (BC), and particle number concentrations were monitored before and during the firework display to understand the effect of the firework display on the short-term air quality. The hourly average concentrations of PM2.5, BC, total particle number, and ultrafine particle number during the firework display (episode period) were 146.9 µg m–3, 2639 ng m–3, 3.37 × 104 # cm–3, and 1.18 × 104 # cm–3, respectively. These values were 6.9, 2.3, 5.9, and 3.7 times greater than those during the same period on reference days (nonepisode period), respectively. The measured ultraviolet BC (UVBC) and BC concentrations indicated that aerosols were bound with ultraviolet-absorbing organic compounds, which were abundant, during the episode period. BC aerosols during the episode originated from vehicular traffic and firecracker burning, and the absorption Angstrom exponent value was 1.4. The particle number size distribution during the episode period showed a major accumulation mode and a minor Aitken mode of 180 and 63 nm, respectively. This particle number size distribution pattern was considerably different from that in the nonepisode period. During the episode period, particle coagulation played a crucial role in removing particles in the nucleation and Aitken modes in the ambient air at high particle number concentrations.

Multi-cell spacing constraints arise due to aggressive scaling and manufacturing issues. For example, we can incorporate multi-cell spacing constraints due to pin accessibility problem in sub-10nm nodes. This work studies detailed placement considering multi-cell spacing constraints. A naive approach is to model each multi-cell spacing constraint as a set of 2-cell spacing constraints, but the resulting total cell displacement would be much larger than necessary. Thus, we aim to tackle this problem and propose a practical multi-cell method by first analyzing the initial layout to determine which cell pair in each multi-cell spacing constraint is the easiest to break apart. Secondly, we apply a single-row dynamic programming (SRDP)-based method one row at a time, called Intra-Row Move (IRM) to resolve a majority of violations while minimizing the total cell displacement or wirelength increase. With cell virtualization and movable region computation techniques, our IRM can be easily extended to handle mixed cell-height designs with only a slight modification of the cost computation in the SRDP method. Finally, we apply an integer linear programming-based method called Global Move (GM) to resolve the remaining violations. Experimental results indicate that our multi-cell method is much better than a 2-cell method both in solution quality and runtime.

Polycrystalline tellurium becomes amorphous after irradiation with strong femtosecond pulses. The amorphization is sensitive to the initial temperature but not very sensitive to the temporal profile of the optical excitation. Above the amorphization threshold, single-shot transient reflectivity traces show clear coherent phonon oscillations within 1 ps. These results suggest that amorphization is due to thermal melting rather than nonthermal melting or switching for pump fluences up to the ablation threshold.

Excursions far from their equilibrium structures can bring crystalline solids through collective transformations including transitions into new phases that may be transient or long-lived. The direct spectroscopic observation of far-from-equilibrium rearrangements provides fundamental mechanistic insight into chemical and structural transformations and a potential route to practical applications, including ultrafast optical control over material structure and properties. However, in many cases, photoinduced transitions are irreversible or only slowly reversible, or the light fluence required exceeds material damage thresholds. This requirement precludes conventional ultrafast spectroscopy, in which optical excitation and probe pulses irradiate the sample many times, each measurement providing information about the sample response at just one probe delay time following excitation, with each measurement at a high repetition rate and with the sample fully recovering its initial state in between measurements. Using a single-shot, real-time measurement method, we are able to observe the photoinduced phase transition from the semimetallic, low-symmetry phase of crystalline bismuth into a high-symmetry phase whose existence at high electronic excitation densities is predicted based on earlier measurements at moderate excitation densities below the damage threshold. Our observations indicate that coherent lattice vibrational motion launched upon photoexcitation with an incident fluence above 10 mJ/cm[superscript 2] in bulk bismuth brings the lattice structure directly into the high-symmetry configuration for several picoseconds, after which carrier relaxation and diffusion restore the equilibrium lattice configuration. Subject Areas: Condensed Matter Physics, Materials Science, Physical Chemistry, United States. Office of Naval Research (Grant N00014-12-1- 0530), United States. Office of Naval Research (Grant N00014-16-1-2090), National Science Foundation (U.S.) (Grant CHE-1111557)

This work presents the reduction of reflection noise in signal trace routing through metal planes with a via stub in a thick multilayered PCB using high-impedance arc traces. The loading effect for signal trace routing through metal planes with a via stub is typically capacitive. Therefore, the high-impedance arc trace can be used to compensate for via impedance. The reduction can be observed in not only the frequency domain ( $S_{11}$ , returned loss) but also the time domain (TDR waveform). The inserted loss $(S_{21})$ with high-impedance arc traces is compared to that without.

We have constructed a noncollinear optical parametric amplifier with two signal beams amplified in the same nonlinear crystal. This dual-beam design is more energy-efficient than operating two amplifiers in parallel. The cross-talk between two beams has been characterized and discussed. We have also added a second amplification stage to enhance the output of one of the arms, which is then frequency-doubled for ultraviolet generation. This single device provides two tunable sources for ultrafast spectroscopy in the ultraviolet and visible region.

We enhance an optical flow cytometer with a photon-number statistics measurement. Our technique allows for an absolute measurement of biomarker concentration and proves sensitivity to a single biomarker (a colloidal quantum dot).

Building materials (BMs) are major contributors to indoor emission sources of volatile organic compounds (VOCs). In this study, 8 kinds of BMs (including conventional and green) for ceiling, cabinetry, and flooring commonly used indoors were tested in a 216 L chamber. Primary emissions of carbonyls (C 1 to C 8 aldehydes and ketones) at 48 h were 75–673 μg m −2 h −1 from conventional BMs, and 62–151 μg m −2 h −1 from green BMs. Primary emissions of BTEX at 48 h were 59–264 μg m −2 h −1 from conventional BMs, and 37–56 μg m −2 h −1 from green BMs. Ozone initiated molar yields of carbonyls were 0.10–2.36 from conventional BMs, and 0.13–0.86 from green BMs. Secondary emissions of carbonyls were 7–150 μg m −2 h −1 from conventional BMs, and 4–73 μg m −2 h −1 from green BMs. Green BMs had lower emissions than conventional analogs, especially for wooden flooring and gypsum board. BMs with mineral content are the most promising materials in this study, given moderately high ozone deposition velocity but generating the least byproducts. Secondary emissions determined in this study demonstrate that moderate indoor ozone concentrations may lead to increased concentrations of carbonyls, especially formaldehyde and acetaldehyde that potentially increase adverse chronic health effects.

Methylglyoxal (MG) has been found to cause inflammation and insulin resistance in vitro and in vivo in recent studies. Resveratrol has been proposed as an effective treatment that helps lower the risk of developing complications of diabetes. To study the significance of glycosylation-related stress on the pathology of diabetes, the effects of resveratrol were examined in a mouse model of diabetes induced by MG. Resveratrol was given via oral gavage in MG-treated mice, and diabetes-related tests and markers were assessed using biochemical and immunohistochemical analyses. Treatment with resveratrol markedly improved blood glucose level from the oral glucose tolerance test and promoted nuclear factor erythroid 2-related factor-2 (Nrf2) phosphorylation (p &lt, 0.05) in the pancreas of MG-treated mice. However, these effects were abolished by retinoic acid, Nrf2 inhibitor, in resveratrol and retinoic acid-treated and MG-induced mice. These findings support that resveratrol may be useful in the treatment of type-2 diabetes by protecting against pancreatic cell dysfunction.

In modern medical technology, there is not only a need for effective surgery operation; reducing mistake during the administration of surgery cannot be ignored. A wireless multiple-lenses panoramic endoscopic system is introduced in this paper. We will outlook the whole system and review several key design technologies. In the software design, there are several programs are developed to assist doctors, including image-stitching, scalpel-tracking, lesions-identification functions. A combination of CPU and GPU heterogeneous computing platform is utilized for surgical image-processing functions. In hardware system design, a dual-voltage dual-core low-power motion estimation chip is adopted to reduce power consumption by 20% ~ 30% in different clock frequency. The whole system integration and animal in-vivo experiment are accomplished.

We have conducted degenerate pump-pump-probe experiments on semimetal bismuth with femtosecond time resolution, varying both pump-probe and interpump time delays. The observed phonon dynamics, including the amplitude, damping, frequency, and phase, can be modeled by the interference of two chirped damped oscillators. No lattice anharmonicity along the trigonal axis is observed. We also find evidence of phonon-mediated relaxation of the energy density at the sample surface.

To promote smart campus, National Chiao Tung University is deploying several location-based IoT applications based on wireless communications technologies including LoRa and NB-IoT. The applications are indoor/outdoor environment conditions monitoring (such as PM2.5, temperature, and humidity), emergency buttons, and so on. This paper uses PM2.5 measurement application as an example to present the performance of LoRa when it is used on campus. We investigated the LoRa transmission performance from LoRa end-devices to the LoRa gateway. We show how packet losses were affected by the distance between the end-device and the gateway, the transmit power, the payload length, the antenna angle, the time of day, and the weather conditions. The pattern of LoRa packet losses were also measured and we found that in our long-term PM2.5 monitoring application, more than 99\% of LoRa packet losses occurred with three or less consecutive packet losses.