bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential cross-species transmission of highly pathogenic avian influenza H5 subtype (HPAI H5) viruses to humans calls for the development of H5-specific and universal influenza vaccines
Authors: Huang Pan , Sun Lujia , Li Jinhao , Wu Qingyi , Rezaei Nima , Jiang Shibo , Pan Chungen
Published: June 2023

In recent years, highly pathogenic avian influenza H5 subtype (HPAI H5) viruses have been prevalent around the world in both avian and mammalian species, causing serious economic losses to farmers. HPAI H5 infections of zoonotic origin also pose a threat to human health. Upon evaluating the global distribution of HPAI H5 viruses from 2019 to 2022, we found that the dominant strain of HPAI H5 rapidly changed from H5N8 to H5N1. A comparison of HA sequences from human- and avian-derived HPAI H5 viruses indicated high homology within the same subtype of viruses. Moreover, amino acid residues 137A, 192I, and 193R in the receptor-binding domain of HA1 were the key mutation sites for human infection in the current HPAI H5 subtype viruses. The recent rapid transmission of H5N1 HPAI in minks may result in the further evolution of the virus in mammals, thereby causing cross-species transmission to humans in the near future. This potential cross-species transmission calls for the development of an H5-specific influenza vaccine, as well as a universal influenza vaccine able to provide protection against a broad range of influenza strains.
Do radiomics or diffusion-tensor images provide additional information to predict brain amyloid-beta positivity?
Authors: Jo Sungyang , Lee Hyunna , Kim Hyung-Ji , Suh Chong Hyun , Kim Sang Joon , Lee Yoojin , Roh Jee Hoon , Lee Jae-Hong
Published: June 2023

The aim of the present study was to predict amyloid-beta positivity using a conventional T1-weighted image, radiomics, and a diffusion-tensor image obtained by magnetic resonance imaging (MRI). We included 186 patients with mild cognitive impairment (MCI) who underwent Florbetaben positron emission tomography (PET), MRI (three-dimensional T1-weighted and diffusion-tensor images), and neuropsychological tests at the Asan Medical Center. We developed a stepwise machine learning algorithm using demographics, T1 MRI features (volume, cortical thickness and radiomics), and diffusion-tensor image to distinguish amyloid-beta positivity on Florbetaben PET. We compared the performance of each algorithm based on the MRI features used. The study population included 72 patients with MCI in the amyloid-beta-negative group and 114 patients with MCI in the amyloid-beta-positive group. The machine learning algorithm using T1 volume performed better than that using only clinical information (mean area under the curve [AUC]: 0.73 vs. 0.69, p < 0.001). The machine learning algorithm using T1 volume showed better performance than that using cortical thickness (mean AUC: 0.73 vs. 0.68, p < 0.001) or texture (mean AUC: 0.73 vs. 0.71, p = 0.002). The performance of the machine learning algorithm using fractional anisotropy in addition to T1 volume was not better than that using T1 volume alone (mean AUC: 0.73 vs. 0.73, p = 0.60). Among MRI features, T1 volume was the best predictor of amyloid PET positivity. Radiomics or diffusion-tensor images did not provide additional benefits.
Evaluation of inactivation of bovine coronavirus by low-level radiofrequency irradiation
Authors: Cantu Jody C. , Butterworth Joseph W. , Mylacraine Kevin S. , Ibey Bennett L. , Gamboa Bryan M. , Johnson Leland R. , Thomas Robert J. , Payne Jason A. , Roach William P. , Echchgadda Ibtissam
Published: June 2023

Inactivation of influenza A virus by radiofrequency (RF) energy exposure at levels near Institute of Electrical and Electronics Engineers (IEEE) safety thresholds has been reported. The authors hypothesized that this inactivation was through a structure-resonant energy transfer mechanism. If this hypothesis is confirmed, such a technology could be used to prevent transmission of virus in occupied public spaces where RF irradiation of surfaces could be performed at scale. The present study aims to both replicate and expand the previous work by investigating the neutralization of bovine coronavirus (BCoV), a surrogate of SARS-CoV-2, by RF radiation in 6–12 GHz range. Results showed an appreciable reduction in BCoV infectivity (up to 77%) due to RF exposure to certain frequencies, but failed to generate enough reduction to be considered clinically significant.
Multi-parental fungal mapping population study to detect genomic regions associated with Pyrenophora teres f. teres virulence
Authors: Dahanayaka Buddhika A. , Martin Anke
Published: June 2023

In recent years multi-parental mapping populations (MPPs) have been widely adopted in many crops to detect quantitative trait loci (QTLs) as this method can compensate for the limitations of QTL analyses using bi-parental mapping populations. Here we report the first multi-parental nested association mapping (MP-NAM) population study used to detect genomic regions associated with host-pathogenic interactions. MP-NAM QTL analyses were conducted on 399 Pyrenophora teres f. teres individuals using biallelic, cross-specific and parental QTL effect models. A bi-parental QTL mapping study was also conducted to compare the power of QTL detection between bi-parental and MP-NAM populations. Using MP-NAM with 399 individuals detected a maximum of eight QTLs with a single QTL effect model whilst only a maximum of five QTLs were detected with an individual bi-parental mapping population of 100 individuals. When reducing the number of isolates in the MP-NAM to 200 individuals the number of QTLs detected remained the same for the MP-NAM population. This study confirms that MPPs such as MP-NAM populations can be successfully used in detecting QTLs in haploid fungal pathogens and that the power of QTL detection with MPPs is greater than with bi-parental mapping populations.
Home range ecology of Indian rock pythons (Python molurus) in Sathyamangalam and Mudumalai Tiger Reserves, Tamil Nadu, Southern India
Authors: Vishnu C. S. , Marshall Benjamin Michael , Ramesh Chinnasamy , Thirumurugan Vedagiri , Talukdar Gautam , Das Abhijit
Published: June 2023

The Indian rock pythons (Python molurus) are classified as a near-threatened snake species by the International Union for the Conservation of Nature and Natural Resources (IUCN); they are native to the Indian subcontinent and have experienced population declines caused primarily by poaching and habitat loss. We hand-captured the 14 rock pythons from villages, agricultural lands, and core forests to examine the species' home ranges. We later released/translocated them in different kilometer ranges at the Tiger Reserves. From December 2018 to December 2020, we obtained 401 radio-telemetry locations, with an average tracking duration of (444 ± 212 days), and a mean of 29 ± SD 16 data points per individual. We quantified home ranges and measured morphometric and ecological factors (sex, body size, and location) associated with intraspecific differences in home range size. We analyzed the home ranges of rock pythons using Auto correlated Kernel Density Estimates (AKDE). AKDEs can account for the auto-correlated nature of animal movement data and mitigate against biases stemming from inconsistent tracking time lags. Home range size varied from 1.4 ha to 8.1 km2 and averaged 4.2 km2. Differences in home range sizes could not be connected to body mass. Initial indications suggest that rock python home ranges are larger than other pythons.
Many-body quantum muon effects and quadrupolar coupling in solids
Authors: Gomilšek Matjaž , Pratt Francis L. , Cottrell Stephen P. , Clark Stewart J. , Lancaster Tom
Published: June 2023

Strong quantum zero-point motion (ZPM) of light nuclei and other particles is a crucial aspect of many state-of-the-art quantum materials. However, it has only recently begun to be explored from an ab initio perspective, through several competing approximations. Here we develop a unified description of muon and light nucleus ZPM and establish the regimes of anharmonicity and positional quantum entanglement where different approximation schemes apply. Via density functional theory and path-integral molecular dynamics simulations we demonstrate that in solid nitrogen, α–N2, muon ZPM is both strongly anharmonic and many-body in character, with the muon forming an extended electric-dipole polaron around a central, quantum-entangled [N2–μ–N2]+ complex. By combining this quantitative description of quantum muon ZPM with precision muon quadrupolar level-crossing resonance experiments, we independently determine the static 14N nuclear quadrupolar coupling constant of pristine α–N2 to be –5.36(2) MHz, a significant improvement in accuracy over the previously-accepted value of –5.39(5) MHz, and a validation of our unified description of light-particle ZPM.
Phytate lithium as a multifunctional additive stabilizes LiCoO2 to 4.6 V
Authors: Zhang Fangchang , Qin Ning , Li Yingzhi , Guo Hao , Gan Qingmeng , Zeng Chun , Li Zhiqiang , Wang Zhenyu , Wang Ruo , Liu Guiyu , Gu Shuai , Huang He , Yang Zelin , Wang Jun , Deng Yonghong , Lu Zhouguang
Published: June 2023

Phytate lithium plays multifunctional roles by coordinating with Co, scavenging free radicals, and flame-retardants, stabilizing LiCoO2 to 4.6 V.
Durable modulation of Zn(002) plane depositionviareproducible zincophilic carbon quantum dots towards low N/P ratio zinc-ion batteries
Authors: Xu Zhu , Li Heng , Liu Yupeng , Wang Kexuan , Wang Huibo , Ge Mingzheng , Xie Junpeng , Li Jielei , Wen Zhaorui , Pan Hui , Qu Songnan , Liu Jilei , Zhang Yanyan , Tang Yuxin , Chen Shi
Published: June 2023

This work not only offers a feasible solution for developing actual high-energy density ZIBs but also provides in-depth insights on the working mechanism of CDs in regulating Zn deposition behaviors.
The relation of cosmic environment and morphology with the star formation and stellar populations of AGN and non-AGN galaxies
Authors: Mountrichas G. , Yang G. , Buat V. , Darvish B. , Boquien M. , Ni Q. , Burgarella D. , Ciesla L.
Published: June 2023

In this work, we study the relation of the cosmic environment and morphology with the star formation and stellar population of galaxies. Most importantly, we examine if this relation differs for systems with active and non-active supermassive black holes. For that purpose, we used 551 X-ray detected active galactic nuclei (AGNs) and 16 917 non-AGN galaxies in the COSMOS-Legacy survey for which surface-density field measurements are available. The sources lie at a redshift of 0.3 < z < 1.2, probe X-ray luminosities of 42 < log[LX,2−10 keV(erg s−1)] < 44, and have stellar masses of 10.5 < log [M*(M⊙)] < 11.5. Our results show that isolated AGNs (field) have lower star formation rates (SFRs) compared to non-AGNs at all LX spanned by our sample. However, in denser environments (filaments and clusters), moderate LX AGN (log[LX,2−10 keV(erg s−1)] > 43) and non-AGN galaxies have similar SFRs. We also examined the stellar populations and the morphology of the sources in different cosmic fields. For the same morphological type, we find that non-AGN galaxies tend to have older stellar populations and are less likely to have undergone a recent burst in denser environments compared to their field counterparts. The differences in the stellar populations concerning density field are mainly driven by quiescent systems. Moreover, low LX AGNs present negligible variations of their stellar populations in all cosmic environments, whereas moderate LX AGNs have, on average, younger stellar populations and are more likely to have undergone a recent burst in high-density fields. Finally, in the case of non-AGN galaxies, the fraction of bulge-dominated (BD) systems increases with the density field, while BD AGNs are scarce in denser environments. Our results are consistent with a scenario in which a common mechanism, such as mergers, triggers both the star-formation and the AGN activity.
Solar-like oscillations inγCephei A as seen through SONG and TESS
Authors: Knudstrup E. , Lund M. N. , Fredslund Andersen M. , Rørsted J. L. , Pérez Hernández F. , Grundahl F. , Pallé P. L. , Stello D. , White T. R. , Kjeldsen H. , Vrard M. , Winther M. L. , Handberg R. , Simón-Díaz S.
Published: June 2023

Context.Fundamental stellar parameters such as mass and radius are some of the most important building blocks in astronomy, both when it comes to understanding the star itself and when deriving the properties of any exoplanet(s) they may host. Asteroseismology of solar-like oscillations allows us to determine these parameters with high precision.

Aims.We investigate the solar-like oscillations of the red-giant-branch starγCep A, which harbours a giant planet on a wide orbit.

Methods.We did this by utilising both ground-based radial velocities from the SONG network and space-borne photometry from the NASA TESS mission.

Results.From the radial velocities and photometric observations, we created a combined power spectrum, which we used in an asteroseismic analysis to extract individual frequencies. We clearly identify several radial and quadrupole modes as well as multiple mixed, dipole modes. We used these frequencies along with spectroscopic and astrometric constraints to model the star, and we find a mass of 1.27−0.07+0.05M⊙, a radius of 4.74−0.08+0.07R⊙, and an age of 5.7−0.9+0.8Gyr. We then used the mass ofγCep A and our SONG radial velocities to derive masses forγCep B andγCep Ab of 0.328−0.012+0.009M⊙and 6.6−2.8+2.3 MJup, respectively.
Thermal alliesthesia under whole-body step-change transients
Authors: Vellei Marika , de Dear Richard , Le Dreau Jérôme , Nicolle Jérôme
Published: June 2023

A better understanding of the psycho-physiological mechanisms driving human thermal perception during dynamic conditions is important to improve physiological-based thermal comfort models. During thermal transients, the two phenomena of thermal overshoot and thermal alliesthesia concurrently affect thermal comfort. However, they have to date been analysed separately. In this paper, we report the results of an experiment exploring the subjective responses of 16 males and 48 females to four different whole-body warm and cool step-change transients at different times of day (morning/afternoon) and in distinct seasons (summer/autumn). We found that time of day and season both significantly affect the relationship between thermal comfort and thermal sensation. This relationship was then used to predict the thermal comfort overshoot which was compared to the actual comfort vote during the step-change transients. This allowed us to separate the contribution to thermal comfort due to thermal overshoot from that attributed to thermal alliesthesia. We could show that, during the step-change transients, positive alliesthesia increases the level of thermal comfort proportionally to the perceived corrective potential of the whole-body discomfort, and this effect gets stronger as we move away from thermal neutrality.
Spatiotemporal distribution prediction of coughing airflow at mouth based on machine learning—Part II: Boundary inference using neural network
Authors: Han Wenqi , Peng Yaqing , Wu Xunmei , Han Mengtao
Published: June 2023

In the post-epidemic era, the trajectory of pathogenic airflows and droplets generated by coughing have been widely studied. However, owing to the limitations of measurement methods, there is a lack of detailed data on their spatiotemporal distribution at the mouth during coughing, which are the basis of research and the critical boundary conditions for computational simulation. Previous experiments have determined the velocity distribution of coughing airflow in spaces located far from the mouth. This study aims to collect detailed data at the mouth for use as the Computational Fluid Dynamics (CFD) boundary conditions from the experimental data. In Part I of this study, the critical parameters that describe the boundary conditions at the mouth for CFD simulation were obtained. Based on these parameters, this part infers the detailed temporal and spatial distribution velocity data of the coughing airflow at the mouth using a neural network. We performed CFD simulation on the prediction results with V=10.76 and M=4, and got FAC2=0.56 compared with the experimental values. The results obtained provided a generic detailed boundary condition for coughing airflow at the mouth and appropriate machine-learning parameters. This study can provide more accurate boundary conditions for simulating the propagation of pathogenic airflow and a supplementary database for epidemic prevention research.
Investigation of the Relationship between Tension Level and Thermal Sensation. A Case Study of University Study Hall
Authors: Özbey Mehmet Furkan , Alkan Neşe , Turhan Cihan
Published: June 2023

The adaptive thermal comfort model steps forth against Fanger's Predicted Mean Vote/ Percentage of Dissatisfied model because of considering the psychological and behavioural adjustments in addition to environmental and personal parameters in mixed-mode and non-air-conditioned buildings. Among behavioural and psychological adjustments, human behaviour is more investigated than psychological adjustments in aspects of thermal sensation and comfort in the studies. To meet the deficit in the literature on how psychological adjustments affect thermal sensation, an experimental investigation was conducted to explore the effects of tension level on the Thermal Sensation Votes (TSV) of the students. Profile of Mood States (POMS) questionnaire was used to determine the tension level of the students. Experiments were conducted in a university study hall which is in the warm-summer Mediterranean climate (Csb) zone according to Köppen-Geiger Climate Classification. A total of 1159 students participated in the study, and the relation between the tension level and TSVs of the students were investigated for each gender. To test the associations between the nine quantitative subscales of tension level and the TSV, Pearson’s correlation coefficient was computed. Based on results, “anxious” were considerable for the TSVs of both genders where the p-values were <0,001 for male and 0,044 for female students. In addition, while “shaky” (p=0,001) and “uneasy” (p<0,001) were found significant for the TSVs of male, “nervous” (p=0,013) were discovered noteworthy for the TSVs of the female students.
Infection Risk Assessment via Agent Simulation with Seat-Choice Behavior
Authors: Matsubara Takumi , Kitajima Yoshiki , Nagano Hideaki , Yanagi U. , Kagi Naoki
Published: June 2023

The human behavior has much impact on the infectious desease spreading. The pathogen generation is not uniform for the residential area since the human have some preference on where to be. The purpose of the present study is to evaluate the impact of the human preference on the seat choice behavior on the pathogen concentration. The preference of the seat selections in a train was modelled and the agent simulation was performed in order to evaluate the non-uniformity of pathogen. The concentration was calculated with Wells-Riley model. The results of the agent simulation showed the preference of seat choice based on the experimental results in a train environment. The seats at the end were more selected than other seats. The concentration at the seats at the end kept increasing because the agent sat there by turns and that is why there was no recovery time. The double effect of the more seat selection and the less recovery time has much impact on the non-uniformity of the concentration.
Investigation of Ultrafine Particle Deposition in Human Airway to the 9th Generation of Bronchial Tubes Using Computational Fluid and Particle Dynamics
Authors: Khoa Nguyen Dang , Phuong Nguyen Lu , Ito Kazuhide
Published: June 2023

The behavior of airborne particles in the human respiratory system is closely related to local tissue dosimetry and its associated health risks. The inhalation of these particles is known to be the origin of lung diseases, such as lung cancer, chronic obstructive pulmonary disease, and cardiovascular disease. To compensate for the difficulty of experiments involving volunteers, in silico studies using numerical models have been adopted as promising alternatives. Therefore, this study applied the computational fluid and particle dynamics technique to investigate the deposition of ultrafine particles in the human respiratory tract from the nostrils to the ninth generation of bronchi. A computational model was created using computed tomography images. The airflow patterns were simulated under steady and incompressible conditions at breathing flow rates of 7.5 and 15 L/min, respectively. The discrete phase was simulated for ultrafine particles with aerodynamic diameters of 2–100 nm. Consequently, the validation work confirmed the simulation accuracy for particle sizes > 25 nm. In the lower respiratory system, the total deposition fraction decreased as the particle size increased. In addition, the eighth generation is a focal point of the deposited particles, elucidated by the local deposition fraction. The results of this study will benefit further studies involving health risk assessments and drug delivery.
Relationship Between Subjective Evaluation of School Environment and Learning Motivation
Authors: Abe Chisato , Hayashi Tatsuya
Published: June 2023

“Proactive, interactive, and authentic learning” has been emphasized in Japanese education, and the consideration of school facilities that can realize such learning has become an urgent issue. In this study, we focused on students’ learning motivation, extracted 12 elements from all school environments as factors that contribute to the improvement of learning motivation, and explored the relationship between the school environment and learning motivation. A questionnaire survey of two junior high schools was conducted to measure subjective evaluations of the school environment and learning motivation. And we performed the univariate analysis using correlation analysis and logistic regression analysis. The results showed correlations between the environmental elements of classroom design, creative space, and peace of mind, and learning motivation. In particular, the total score of school environment correlated more strongly with learning motivation than the other environmental factors. The results also suggested that the elements of the school environment may lead to higher learning motivation through 4 factors for improving learning motivation and other factors. It is necessary to clarify the relationship between school environment and learning motivation through more structural analysis in the future.
Evaluation on present situations of safety on thermal environment in residential houses in Japanese winter season using BEST-H program
Authors: Yoshida Shinji
Published: June 2023

In this paper, the present situations on the safety of thermal environment in residential houses in winter season were evaluated by using the BEST-H program, a computation tool for analysing the thermal load in residential houses. In this analysis, the climate conditions for each primary division area in Japan were imposed to the input conditions for the thermal load computations. We also evaluated the safety of thermal environment with the hazard rate for both the cardiac and the brain diseases from the combination between the computational results using the BEST-H program and the several statistical data. Through the investigations, the following two findings were obtained: (1) the proposed method was validated for the evaluation of the safety on the thermal environment in the residential houses in winter season by comparing the computational results with the statistical data from the Population Survey Report in Japan.: (2) More houses with suitable insulation performance should be established in the western area and northern part of the Kanto area in Japan. The near future direction of our study is to evaluate variable countermeasures, such as one-room insulation.
Decoding human perception for building indoor environmental comfort: Testing the Hue-Heat-Hypothesis via physiological and psychological response analysis
Authors: Pigliautile Ilaria , Rosati Antonella , Mansi Silvia Angela , Arnesano Marco , Pisello Anna Laura
Published: June 2023

The recent energy crisis limits humans’ adaptation capability to climate change in indoors, making access to active air conditioning prohibitive. Since lighting systems are less energy-consuming then conditioning systems, this work focuses on visual stimuli to affect occupant’s thermal perception in the framework of the multi-domain comfort theory. Despite the Hue-Heat-Hypothesis has already been explored, validation is still missing. The following hypotheses were outlined: (i) different coloured lights lead to changes in thermal perception that are stronger under thermally comfortable conditions; (ii) visual and thermal domains synergistically interact on the overall comfort perception; (iii) skin temperature can be used as a proxy for thermal comfort. 24 volunteers were exposed to 9 scenarios combining 3 types of coloured light (white, blue, and red) with 3 temperature levels (cool, neutral, and warm conditions). Perceptual responses were collected through questionnaires and skin temperature was measured through wearable. Results support the hypothesis that bluish lights lead to cooler sensation especially in a thermally neutral environment. Skin temperature, mainly affected by ambient temperature, was not significantly related to expressed thermal comfort, apparently in contrast with previous literature results, which may highlight an interfering role of coloured lights on investigated thermal perception as cross-modal effect.
Impacts of glazing system design factors upon dynamic indoor thermal comfort incorporating solar radiation effects
Authors: Fang Pei-Lun , Lu Yu-Jie , Chen Wei-An , Hwang Ruey-Lung
Published: June 2023

Solar radiation makes great influence on human perception of thermal balance and comfort. This study investigated the effect of glazing system design factors on thermal comfort in the presence of solar radiation and aims to clarify the relationship between glazing system performance and thermal comfort through simulations. Specifically, a cellular office unit with different window sizes, glazing types, and shading devices was set for simulating the thermal environment based on an integrated MRT algorithm that considered both longwave radiation from inner surfaces and shortwave solar radiation. The temporal and space thermal comfort were evaluated through long-term metrics including space Thermal Comfort Availability (sTCA) and temporal Thermal Comfort Usability (tTCU). Under the climatic conditions in Taiwan, it was found that SHGC makes greatest influence on sTCA/tTCU, followed by window size and overhang depth. Eventually, an additive model was chosen to construct the functional relationship between sTCA/tTCU and the main effects of three important parameters as well as their interactions. The simple and quick method we established is believed to be helpful to architects in the preliminary evaluation of the space dynamic thermal comfort of the design scheme in the early design stage.
Managing harmful floor emissions including 2-ethylhexanol by using an emissions barrier
Authors: Larsson Lennart , Mattsson Johan
Published: June 2023

The present communication describes the use of an emissions barrier to prevent spread of hydrolysis products from plastizisers in plastic mats and from the glue used to attach such mats onto a concrete slab. In particular, 2-ethylhexanol was focussed at. Elevated air concentrations of 2-ethylhexanol has been associated with a range of health symptoms such as e.g. cough, airways irritation, fatique, skin and mucous membrane irritation. Here we describe how such health problems can be avoided by using an emissions barrier.
Research on partially optimized air conditioning system in station space
Authors: Takagi Kenji , Miura Katsuhiro , Kaneko Hiroyuki , Kashiwa Takayuki , Takase Atsushi
Published: June 2023

There are expectations recently for improving comfort in railway stations. The need to mitigate hot environments in stations in summer is especially strong. The purpose of this study was to investigate the achievement of thermal comfort in summer in railway stations while conserving energy, not by cooling down the whole area but by utilizing localized air conditioning systems. A field study was first conducted in an underground station concourse, measuring the thermal environment, surveying equipment that dissipates heat, and examining occupant density. Under existing conditions, the highest daily interior air temperature was almost the same as that outside the station, while the lowest temperature was higher than that outside; air velocity inside was low. Study results led to the conclusion that a localized air conditioning system utilizing air movement is effective in improving comfort, and to the development of a localized air conditioning system effective for special module concourses in railway stations. A planning method for selecting effective locations for the system is proposed. An evaluation of the system using actual devices was conducted in a mock-up spaces. The CFD simulation in an actual station concourse showed improved thermal comfort using the developed system.
Development of an adaptive model for thermal comfort in the office buildings of Nagasaki City, Japan
Authors: Genjo Kahori , Oki Momoka , Nakanishi Haruna , Imagawa Hikaru , Uno Tomoko , Saito Teruyuki , Takata Hiroshi , Tsuzuki Kazuyo , Nakaya Takashi , Nishina Daisaku , Hasegawa Kenichi , Mori Taro , Rijal Hom B.
Published: June 2023

Thermal comfort in office buildings is instrumental in improving the productivity of employees while maintaining their health. The primary objectives of this research were to analyze the comfort temperature in Japanese office buildings and investigate its relationship with outdoor air temperature. Additionally, we examined the differences in comfort temperatures with respect to closed and opened windows to factor in the increase in the opening of windows during the COVID-19 pandemic when air-conditioning systems were operated. We investigated the environmental conditions of office buildings and the thermal comfort of the occupants through monthly visits to each office building over a year. Field data were collected from four office buildings located in Nagasaki City, with 1047 votes obtained from 143 participants. The survey indicated that the occupants were highly satisfied with the thermal environment in their offices. The correlation between indoor comfort temperature and outdoor temperature was high in the FR mode. Based on the analysis, we developed an adaptive model for office buildings in Nagasaki City and compared it with existing adaptive models used for buildings in other regions of Japan. The proposed model is useful for energy-saving designs that bring out human adaptive capacity.
Effect of an Air Cleaner Based on Age of Air Distribution Measurement Using the Dynamic Steady-State Concentration
Authors: Ri Hiko , Kurabuchi Takashi , Kim Jeongil , Takeuchi Jinya , Yoshino Hajime , Toriumi Yoshihiro , Taguchi Haruki , Furusawa Arisu
Published: June 2023

This study aims to determine the range of the effect of an air cleaner in indoor environments. The age of air is often used to evaluate the ventilation performance in indoor air environments, and step-down tracer gas methods are widely used in open-air systems in ventilation rooms. However, conventional experimental methods cannot be used to measure the age of air in air recirculation systems such as an air cleaner that do not have a ventilation system. Previous studies have shown that the dynamic steady-state concentration correlates with the equivalent steady-state concentration in the ventilation room of an open-air system. In this study, we investigated the possibility of determining the age of air by measuring the dynamic steady-state concentration generated in a real space. First, we used the tracer gas experimental technique based on the dynamic steady-state concentration to measure the age of air in a real space when an air cleaner was used. We then performed simulations to confirm the age of air distribution obtained from the tracer gas experiment using computational fluid dynamics (CFD) analysis. A comparison of the experimental and CFD analysis results showed that the effect of an air cleaner covered the entire room.
Influence of Indoor Environment Changes in Relaxation Space on Relaxation and Refreshment Effects of Occupants
Authors: So Natsumi , Yamanaka Toshio , Choi Narae , Takemura Akihisa , Kobayashi Tomohiro , Fujie Tomoki , Ikeda Kaoru
Published: June 2023

Since proper break between office work is helpful in decreasing work-related stress and fatigue, a break space in office is also an important place to create healthy and productive workplace environment. However, there are relatively few studies focused on the break space compared to ones focused on work space. In this study, experiments were carried out to investigate the influence of the break space’s indoor environment on occupants’ psychological and physiological responses. To examine whether change in indoor environment during break positively affect occupants’ responses and productivity, lighting, odor and air movement conditions were intentionally changed before the end of the break. As for the psychological response, there was a possibility that it would be affected when the lighting and air movement were changed. As for brain waves, effects were also observed when lighting and air movement were changed. In terms of productivity, performance was better when the environment was changed than when the environment was left unchanged during breaks. The need for breaks was indicated because the worst results were obtained when the work was done continuously without a break in the first place. The best results were obtained when the environment was changed to generate an odor.
A CFD approach to reduce the risk of Covid-19 airborne transmission in a typical office
Authors: Hu Yibing , Shen Jialei , Zhang Jianshun Jensen , Gao Zhi
Published: June 2023

The Covid-19 virus can spread rapidly in the air and cause the epidemic to rage around the world. This study takes a typical office as the research object and proposes four different partition settings to suppress the spread of the virus in the air based on displacement ventilation. And these strategies are verified by DPM model simulations of two daily situations of indexed person for coughing and talking. This study then employed a modified Wells-Riley model to evaluate the effectiveness of these strategies in mitigating the risk of viral infection. As expected, in the absence of a partition, a susceptible person at the other end of the seat greatly increased the risk of infection. Partitions can significantly reduce the risk of infection (100% → 20%), while partitions with a full-wrapped structure can reduce the risk of infection to less than 1%. For the instantaneous release scenario of coughing, the barrier can capture a large particle diameter (>50 μm) particles, and the smaller particle diameter can be discharged out of the room with the thermal plume. The strategies provided in this study can provide recommendations for indoor epidemic prevention and control in the context of the Covid-19 pandemic.
Adaptive thermal comfort for energy saving office building design- A literature review
Authors: Lamsal Prativa , Bajracharya Sushil Bahadur , Rijal Hom Bahadur
Published: June 2023

Office building thermal environment quality is essential since thermal comfort and worker productivity are closely related. As thermally comfortable condition is determined by the climate, geography, and surroundings, it is vital to have thermal comfort standards to guide the building designers to create a comfortable indoor thermal environment. The current paper reviews studies on adaptive approach of thermal comfort carried out in offices across the world. It has analyzed many research papers through Scopus. This study reveals that indoor thermal condition is impacted by outdoor climates and the impact is higher in naturally ventilated building. Building with natural ventilation has 17.6°C to 31.2°C rage of comfortable temperature. Adaptive comfort models have also been proposed to predict the comfortable indoor temperature in different modes. According to several studies, lowering the set point and using natural ventilation may result in considerable energy savings. The importance of developing climate specific thermal comfort guidelines in order to create energy efficient designs is also emphasized in this study, as present comfort standards may not be suitable for all climates.
Effects of air temperature and humidity on sleeping women by the ventilation and air-conditioner, Japan
Authors: Tsuzuki Kazuyo , Nabeshima Yuki , Kaku Junko , Shibayama Yoriko
Published: June 2023

The effect of ventilation system on the sleeping persons has not been well studied. This is because mechanical ventilation systems had not previously been widely used in residential buildings in Japan. However, 24-hour mechanical ventilation is now mandatory in highly airtight and insulated houses. This study compared the temperature and humidity in bedrooms using either regular mechanical ventilation or desiccant ventilation when the air conditioner was switched off by a timer. The experiments investigated the sleep quality, thermoregulatory responses, and thermal comfort of young woman participants during the sleeping period at night. The desiccant ventilation reduces the air temperature and humidity by 1 °C and 20% Rh, respectively. While the air conditioner was turned off, the women’s skin temperatures increased by about 0.5 °C, but did not increase awakenings, as a result, the sleep efficiency was maintained at 96%. Thermal and comfort sensations were obtained significantly on the cooler and more comfortable side with the desiccant ventilation system than without desiccant system.
Analysis of Impacts of Window Opening Behavior on Indoor Air Pollutants in Residential Dorms through Deep Neural Network
Authors: Pandey Pratik , Dong and Bing
Published: June 2023

People spend more than 90% of their time in buildings. The highly stochastic behavior of occupants can alter the pollutants concentration in an indoor space. Many studies have reiterated that window opening is one of the best methods to reduce indoor pollutant concentration. In this study, we analyzed the influence of window opening behavior on indoor pollution parameters (CO2 and TVOC) in 16 student dorms in Syracuse, NY. The duration of the study encompasses all major seasons of a whole year. We found that the window opening behavior of the living room is triggered by the increased concentration of indoor pollutants. The impact of the window opening on the dilution of the concentration of the indoor pollutants is analyzed using the air exchange rates. We found that the average infiltration air exchange rate is 0.32 h-1 and the average air exchange rate during the window opening is 2.20 h-1. The exchange rates are different in different homes; infiltration ACH range from 0.31 - 0.83 h-1, and window opening ACH range from 0.46 - 3.86 h-1. The mean indoor CO2 concentration for all homes ranges between 458 - 715 ppm, and the mean TVOC concentration is 268 - 1786 ppb. The average error in the loss rate calculated from the mass-balance model and the blower door test is 2.51%. We made a Deep Neural Network model predict the concentration of CO2 in the indoor space based on the window's state. The DNN model has an RMSE of 7 ppm and a MAPE of 6.66%. The DNN predicts that the exposure during decay events at the window opening is 80.31% lower than during closed state decay.
Exploring the effects of spectral light exposure on University students' sleep quality: A cross-sectional study
Authors: Khanie Mandana S. , Illum Trine , Hosseinpour Negin , Matsuo Kazuya , Fan Xiaojun , Wargocki Pawel
Published: June 2023

In developed nations, 2/3 of the population fail to obtain the recommended 7-9 hours of sleep, with large consequences for health and productivity. A potent stimulus in regulating sleep and wake balance is light received at a light-sensitive retinal protein called melanopsin, found in our retinal cells, otherwise known as intrinsically retinal ganglion cells (ipRGCs). Hence, to better understand the effects of bedroom indoor environmental quality IEQ on sleep, we set up a study to objectively explore the impact of spectral light exposure through non-visual pathways on the participants' sleep quality. For one week, University students measured IEQ in their bedrooms while monitoring their spectral light exposure during the day and sleep quality at night. The students were asked to keep the bedroom environment unchanged for the measurement period. Our preliminary results show trends between 7-day accumulative light exposure and length of deep sleep. This trend is not significant, and further in-depth analysis is needed. Among other limitations in the processed data, the diverse and mixed demographic of the sample was not considered. The students' living conditions (single vs. family, accommodation, etc.) varied in this initial analysis.
Changing the direction of the luminaire: A strategy to improve lighting energy efficiency in offices
Authors: Zhou Jiayi , Zeng Yunyi , Yu Juan , Lin Borong
Published: June 2023

Light environment’s non-visual effects influence people’s health and work efficiency. However, considering non-visual requirements in addition to traditional visual requirements may significantly increase lighting energy consumption. This study utilized simulation software to explore energy saving potential of changing the direction of the luminaire. A model of a single-person office with the luminaire attached to the ceiling right above the workstation was built in ECOTECT. Vertical eye-level illuminance and horizontal work-plane illuminance were calculated with luminaires of different luminous fluxes and elevation angles from downward vertical (0°-180° at an interval of 10° on both sides) using RADIANCE. Furthermore, six cases of different lighting requirements and light correlated color temperatures were considered. Based on the illuminance-versus-luminous flux coefficients obtained from simulation results, luminous fluxes were calculated to fulfill both visual and non-visual requirements under different elevation angles in all cases. It was found that compared to traditional lighting design with the luminaire facing vertically downwards, turning the luminaire at an elevation angle of 50° reduced the required luminous flux by up to 22.7%, which would benefit energy savings. Therefore, changing the direction of the luminaire has the potential to improve office lighting energy efficiency when considering both visual and non-visual requirements.
Study on particle filtration performance of high volume air purifier: Experimental results
Authors: Fan Yingying , Liu Junjie , Li Hanyu
Published: June 2023

With the spread of SARS-CoV-2 virus all over the world, the indoor air quality of commercial buildings has received intense attention. The evaluation of high-volume air purifiers (HAP, CADR≥800m3/h) is of unprecedented importance. According to the national standard GB/T 18801-2015, the purification performance of HAP and its three different replacement elements was tested by the environmental chamber method. The results show that the particulate matter purification of single effect filter is better than that of composite filter. The presence of particulate matter generated by activated carbon layer and bypass air flow leads to a difference of about 10% between the clean air delivery rate (CADR) value for the count and weight of composite filter. In the durability test, the CADR value decreases greatly when the smoke volume is 1000 pieces due to the increase of resistance and the electrostatic elimination effect of incense smoke. The CADR test standards of air purifiers in 5 countries were compared. Only Korea mentioned that when the air volume of the air purifier is greater than 960m3/h, 50m3 test chamber is used. However, due to the different sources of experimental dust and sampling methods, this standard does not conform to China's national conditions. The analysis results will provide reference for the formulation of relevant test methods and standards
Effects of the Corona Pandemic on Indoor Fine Dust in Urban Schools
Authors: Lee Jae Uk , Lee Tae Jung , Koo Junemo , Jo Young Min
Published: June 2023

Corona pandemic restricted industrial activity of the country, influenced social activities of people, and changed students' school programs. PM10 and PM2.5 measured in National Air Quality Monitoring Systems were reduced from 36.1 μg/m3 to 34.5 μg/m3, and from 20.3 μg/m3 to 18.5 μg/m3, respectively. In particular, obvious decrease of indoor PM2.5 with high dependency on outdoor air quality was estimated. As a result of precise field tests in 179 classrooms of 53 schools, indoor PM2.5 showed a low average, 23 μg/m3, and PM10 also was lower 33 μg/m3 than before and after the pandemic (51 μg/m3 and 59 μg/m3 respectively). Due to a variety of class work, limited attendance, air purifier operation and frequent window opening, it was not easy to drive a consistent impact of the Corona pandemic at the indoor PM level. Consequently, the indoor and outdoor airborne fine dust concentrations became more similar than normal conditions, and indoor emission amount of PM10 in particular decreased.
Study of the low moving efficiency of bioaerosol with insufficient air inflow and exhaust in the public toilets
Authors: Lee Jeffrey M.C. , Tham K.W. , Pan C.Y. , Tseng H.T.
Published: June 2023

Due to insufficient ventilation, public toilets have become incubators for cross-infection during the pandemic. WHO has proposed an approach to improve indoor ventilation, including ventilation in isolated spaces like toilets, by applying the 10L/s/person criteria, and keeping fans running for effective ventilation. However, less air inflow in many public toilets causes the insufficient ventilation. We have ever found many colony forming units (CFUs) staying surrounding floor and junctures, and the inside of a lid-less trash can in the toilet. If the minimal exhaust air is not equal to inlet air, the bioaerosol will stay in the toilets. Therefore, the speed of air inflow is suggested to be somewhat higher and reach 0.5m/s or more to facilitate ventilation in public toilets and reduce the risk of cross-infection.
Transfer and escape characteristics of outdoor pollutants into an indoor space sheltered by urban-like block arrays using large-eddy simulations
Authors: Fernandez Ken Bryan , Ikegaya Naoki , Ito Kazuhide
Published: June 2023

We conducted isothermal large-eddy simulations to generate the velocity and concentration distributions to investigate the air pollution transport from outside to inside of a space surrounded by urban-like block arrays. Contrary to previous study, we assumed that the pollution in the form of scalars are generated outdoors and not indoors which we placed at: 1) middle of window, 2) near window wall, 3) middle of street canyon at ground level, and 4) middle of street canyon at window level. Results showed that regardless of scalar source location, the scalars accumulated inside the indoor space which can be explained by the downdraft effect that are typically found in urban environments. The downdraft effect produced vortices outside and inside the indoor space. For scalars near window, indoor vortex drove the concentration to indoors. On the other hand, outdoor vortex transported the scalars located at street canyon to reach the window where they were eventually transported to indoors also due to indoor vortex. The average normalized indoor concentrations found in this study are 1.25 – 1.50, 1.00 – 1.75, 0.25 – 0.50, and 0.0 – 0.25 for scalars C1, C2, C3, and C4, respectively. Our study suggests that for natural ventilation studies of urban environments where air pollution is significant, outdoor effects should also be carefully considered.