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Introduction: The Japan Lung Cancer Society (JLCS) and the Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma (JLCS-JSCC system). Prior to the proposal, the Papanicolaou Society of Cytopathology (PSC) had proposed a revised reporting system (PSC system), which comprises the “neoplastic, benign neoplasm, and low-grade carcinoma” category (N-B-LG category), in addition to the 4 categories of the JLCS-JSCC system. This study aimed to evaluate the interobserver agreement of the JLCS-JSCC system with an additional dataset with more benign lesions in comparison with the PSC system. Methods: We analyzed 167 cytological samples, which included 17 benign lesions, obtained from the respiratory system. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the JLCS-JSCC system and PSC system. Results: The interobserver agreement was moderate in the JLCS-JSCC (k = 0.499) and PSC (k = 0.485) systems. Of the 167 samples, 17 samples were benign lesions: 7 pulmonary hamartomas, 5 sclerosing pneumocytomas, 2 squamous papillomas, one solitary fibrous tumor, one meningioma, and one lymphocytic proliferation. There were diverse sample types as follows: 11 touch smears, 3 brushing smears, 2 aspirations, and one sputum sample. Fourteen samples (82.3%) were categorized into “negative” or “atypical” by more than half of the observers in the JLCS-JSCC system. Conversely, 3 samples were categorized as “suspicious” or “malignant” by more than half of the observers in the JLCS-JSCC system. On the other hand, 11 samples (64.7%) were categorized into the N-B-LG category by more than half of the observers in the PSC system. Conclusions: The concordance rate in the JLCS-JSCC system was slightly higher than that in the PSC system; however, the interobserver agreement was moderate in both the JLCS-JSCC and PSC systems. These results indicate that both the JLCS-JSCC and PSC systems are clinically useful. Therefore, both systems are expected to have clinical applications. It may be important to integrate the 2 systems and construct a universal system that can be used more widely in clinical practice.

The National Aeronautics Space Administration Task Load Index (NASA-TLX) is the most frequently used mental workload assessment method. This article reviews 26 papers which report mental workload evaluation in health care staff, categorizing them into laparoscopic surgery, anesthesia, ICU, electronic record, patient controlled analgesia, emergency, display and others. Although indices other than NASA-TLX were also used in these papers, this review describes the results of NASA-TLX only.

Introduction: The classification of lung carcinoma is based on small biopsies and/or cytology in 80% of patients with non-small cell carcinoma. However, there is no widely accepted classification system for respiratory cytology. The Japan Lung Cancer Society (JLCS) and Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma with the following categories: (1) “negative for malignancy,” (2) “atypical cells,” (3) “suspicious for malignancy,” and (4) “malignancy.” Objective: The aim of this work was to perform an interobserver reproducibility study to confirm the utility of the four-tiered reporting system on respiratory cytological samples. Methods: We analyzed 90 cytological samples obtained with bronchoscopy. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the three-, four-, and five-tiered reporting systems. Results: The interobserver agreement was fair in the three- (κ = 0.50), four- (κ = 0.45), and five-tiered (κ = 0.45) reporting systems. However, the four-tiered reporting system provided more precise information than the three-tiered reporting system in patient management. The risk of malignancy in the four-tiered reporting system was also stratified well: 19.3% for “negative for malignancy,” 45.6% for “atypical cells,” 74.7% for “suspicious for malignancy,” and 88.1% for “malignancy.” Conclusions: The reporting system proposed by the JLCS and JSCC was designed to enhance the communication between clinicians and pathologists and among different institutions. It is simple and applicable to cytological diagnosis of any respiratory diseases. We propose establishing an international classification for respiratory cytology, harmonizing the reporting systems proposed by different countries.

Background According to the WHO classification for lung cancer, adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) have a better prognosis than invasive adenocarcinoma (IAD). However, detecting the foci of invasion in lung adenocarcinomas radiologically remains difficult. The present study examined whether or not differences in the cytological characteristics between IAD and AIS or MIA (noninvasive or minimally invasive adenocarcinomas [NMIAD]) plays a role in the differential diagnosis. Methods Seventy surgical resection specimens of primary lung adenocarcinoma with preoperative cytology, in which several parameters were evaluated and assessed. Results The histopathological diagnoses of surgical resection specimens were AIS in 8, MIA in 31, IAD in 31 including lepidic adenocarcinoma in 9, and papillary adenocarcinoma in 22. NMIAD had a 100% 5-year recurrence-free survival (RFS), while IAD had an 82.8% 5-year RFS. The numbers of tumor cells (at ×10 magnification in 10 fields) were 60.3 ± 40.5 in IAD and 39.8 ± 28.7 in NMIAD (P = 0.0017). A univariate analysis of cytological parameters revealed significant differences in large tumor cell clusters, three-dimensional (3D) tumor cell clusters, and irregular nuclear contours between the two groups. The frequency of irregular nuclear contours continued to be significantly different according to a multivariate analysis. Conclusion Large or 3D tumor cell clusters and irregular nuclear contours may be important cytological factors for distinguishing IAD from NMIAD, with the latter being potentially more important for distinguishing between the two groups.

In this study, we investigated relationship between task characteristics such as sensory intake and cardiovascular responses. Nineteen male participants were asked to perform a mental arithmetic task (MA) and a computerized mirror tracing (MT) task for five minutes each. In the MA task, participants were instructed to respond within five seconds by pressing the left or right mouse button. Therefore, this task includes a high time pressure (temporal restriction). In the MT task, participants were required to trace a zigzag pathway displayed on a PC screen by using a mouse. The horizontal and vertical control elements of the mouse were exchanged with each other. This task contains a sensory intake characteristic which induces parasympathetic dominance resulting in bradycardia. ECG and arterial blood pressure were continuously recorded during the two task blocks and before (PRE) and after (POST) resting periods of five minutes each. Heart rate variability indexes such as low frequency (LF) component, high frequency (HF) component and LF/HF ratio were derived. In the results, heart rate (HR) was considerably larger in the MA compared to PRE. On the contrary, the HR change was small in the MT, suggesting that the physiological response in MT is a pattern 2 type which is typically induced by a sensory intake task, although no significant difference was found between the two tasks. Systolic blood pressure (SBP) and Diastolic blood pressure (DBP) were higher in the MT than MA, but there was no significant difference between them. Both SBP and DBP were significantly higher in the task periods than resting periods. Significant differences were found only between PRE and MT, and PRE and POST in LF/HF which showed the highest value in POST, suggesting that the LF/HF ratio is not a reliable mental workload index.

Introduction It is important to evaluate when and why the mental workload of operators increases during system operation. The city traffic control center (TCC) is a complex work system, and it is important to describe MW as a condition related to this. The purpose of this study is to evaluate the mental workload of operators while monitoring traffic loads in the city TCC. Methods Electroencephalography and electrooculography data were collected from 16 operators while performing their daily work, in four conditions: resting state, low traffic density, high traffic density, and recovery. The Simplified-Subjective Workload Assessment Technique (S-SWAT) was used to evaluate the subjective workload of operators. Results The findings indicate that operators experience a larger mental workload during high traffic density than during low traffic density ( p p Conclusion Although the working situations of TCC operators are repeated daily, their mental fatigue and stress level gradually increase, leading to deterioration in their mental health. It may be necessary periodically to monitor their mental health and to consider their organizational behavior during traffic density monitoring. Relevance to industry complex work systems have increased the requirement for many operators to conduct mental tasks in real work conditions such as city traffic density monitoring. When evaluating such workplaces, it is important to identify situations requiring increased mental workload that might impose additional stress on operators, decreasing their performance. Based on the results, the traffic control center director would be aware of the MW condition of the operators.

We investigated the validity of heart rate variability (HRV) as an autonomic nervous system (ANS) assessment method and also investigated the correlations between all pairs of several indices obtained from ECG signals during a task performance. We recorded ECGs from 18 healthy participants during two 30-min mental tasks, i.e., a word processor typing task and a mental arithmetic task, and calculated five indices of HRV spectral analysis and five parameters from the Poincare plot. In the results, significant correlations were found among the participants between LF and SD2 and between HF and SD1. There were no significant differences in the correlation coefficients between the two tasks, and no subjective scores correlated with physiological indices. The correlation coefficients between the sympathetic nervous system activity indices such as LF/HF ratio and CSI, however, were not very high, and these results were different from previous studies. Based on these results, we investigated the correlation coefficient time series in each participant and found that there were fluctuations in correlation coefficients between two indices which had been reported in other studies to indicate the same ANS activity. It was clarified that weak correlations among participants occurred by the fluctuations of correlation coefficients obtained in each participant.

We investigated the effect of age on heart rate (HR) responses and subjective mental workload during mental tasks. In this study, 55 male participants performed a mental arithmetic (MA) task and a mirror tracing (MT) task for 5 min each. Electrocardiogram (ECG) was recorded during these mental tasks and resting periods. Low frequency component (LF), high frequency component (HF), and LF/HF ratio of heart rate variability (HRV) were derived from ECG signals. NASA Task Load Index (NASA-TLX) was used to evaluate the subjective mental workload during each task. In the results, HR was significantly larger in the MA task than the resting period. LF was significantly smaller in the MA than the resting period before the task. On the other hand, no HR changes from the baseline in the MT task were found, suggesting that Pattern 2 response might appear. In the results of HRV indices, decrease in LF suggests the inhibition of the parasympathetic nervous system activity by the task. These results are consistent with those of our previous studies. No significant main interaction with age and blocks (MA, MT and resting periods) were found in physiological responses except for LF/HF and subjective mental workload score. Therefore, the physiological responses induced by mental tasks might be more susceptible to task characteristic than to aging. This study partly supported the previous study.

This study evaluated operators' mental workload while monitoring traffic density in a city traffic control center. To determine the mental workload, physiological signals (ECG, EMG) were recorded and the NASA-Task Load Index (TLX) was administered for 16 operators. The results showed that the operators experienced a larger mental workload during high traffic density than during low traffic density. The traffic control center stressors caused changes in heart rate variability features and EMG amplitude, although the average workload score was significantly higher in HTD conditions than in LTD conditions. The findings indicated that increasing traffic congestion had a significant effect on HR, RMSSD, SDNN, LF/HF ratio, and EMG amplitude. The results suggested that when operators' workload increases, their mental fatigue and stress level increase and their mental health deteriorate. Therefore, it maybe necessary to implement an ergonomic program to manage mental health. Furthermore, by evaluating mental workload, the traffic control center director can organize the center's traffic congestion operators to sustain the appropriate mental workload and improve traffic control management.

The purpose of this study is to examine the test/retest consistency of physiological responses induced by mental tasks. Fifteen healthy male university students were recruited as participants. They were instructed to perform a 5-min Multi-Attribute Task Battery (MATB) trial three times successively. The task difficulty level of the tracking task of the second trial was set as medium (M). The first one was set as more difficult (H) and the last trial was easiest (L). The difficulty levels of the other two tasks (resource management and system monitoring) of the MATB were identical for all three trials. The participants repeated this procedure on three different days separated by at least a 1-day interval. The order of the tasks was the same for all repeated trials, i.e., H-M-L. Tissue blood volume from the tip of the nose using a laser Doppler blood flow meter, skin potential level (SPL), ECG from three leads on the chest, systolic time intervals (pre-ejection period, left ventricular ejection time), and hemodynamic parameters (stroke volume, cardiac output) were recorded during the task trials and before and after 5-min resting periods. The participants reported their subjective workload via NASA-TLX after each task trial. Autonomic nervous system parameters derived from the above-mentioned signals, subjective workload scores, and performance indices of MATB were analyzed, and test/retest reliability was investigated. The results showed that a significant test/retest correlation was obtained for SPL for more participants than in the other parameters, although there were large individual differences.

The anodic performances of Ni/CeO2–Sm2O3(Ni/SDC) modified by the addition of alkaline earth metal oxides (MgO, CaO, and SrO) were investigated for direct oxidation of CH4 in solid oxide fuel cells (SOFCs). Although the initial power density of cell with Ni/SDC anode modified by the addition of CaO was slightly lower than that of cell with Ni/SDC, the former anode exhibited an excellent stability compared to the latter one. Such a high stability of Ni–CaO/SDC anode may come from the inhibition of carbon deposition in addition to the retained ionic conductivity of anode. Keywords: Solid oxide fuel cell, Nickel anode, Samarium-doped ceria, Alkaline earth metal oxide, Carbon deposition, Direct oxidation of CH4

近年，労働者の精神的ストレスは増大しており，ストレス評価機器の開発が求められている．我々はこれまでにストレスの定量評価のための研究を行ってきたが，過去の結果において，作業後の生理反応が作業前の状態に完全に回復しない場合が認められた．その原因を探るため，本研究では，作業時および作業後の感情状態と生理反応の関連性を明らかにすることを目的とした．18名の健常な男性に4段階の難易度に設定した計算課題を遂行させ，作業時および作業後に生じた感情状態と生理量を記録した．その結果，作業時には，RR間隔（RRI）と皮膚電位水準（SPL）が満足感や集中度の因子と関連する可能性が示唆され，鼻部血流量（TBF_N）と指尖容積脈波振幅（PTG）が低下した．作業後では，どの生理量と感情状態にも関係は認められなかった．また，RRIとSPLは作業後すぐに回復したが，TBF_NとPTGは回復に時間を要することが示唆された．

複雑な現代社会において日常的に受けている精神的ストレスを定量評価するための様々な研究が行われている．先行研究にて，生理反応は，作業中の周囲の状態によって生じる感情変化の影響をうけることが報告されている．そこで本研究では，難易度の異なる精神作業を行わせることによって，被験者の感情を変化させ，生理反応と感情変化の関連性を明らかにすることを目的とした．21～32歳の健康な男子大学院生に難易度の異なる計算作業を遂行させ，種々の自律神経系指標を計測するとともに，主観的ワークロード，気分および作業に対する感情を評価させた．その結果，精神作業によって誘発される生理反応には，実験そのものに対する不安などの感情が影響しており，皮膚電位水準と血圧がそれらの要因に敏感に反応することが示された．

The electrochemical performances and the morphologies of Ni/SDC anodes fabricated by EPD technique were investigated for direct oxidation of dry CH4 in solid oxide fuel cells (SOFCs). Ni/SDC(EPD) anode with both 20 wt% of Ni content and 20 μm of thickness exhibited the lowest overpotential and the highest maximum power density for dry CH4–air SOFC at 973 K. The power density of the cell with Ni/SDC(EPD) anode was higher than that with Ni/SDC fabricated by a conventional slurry coating method. It was found that Ni/SDC(EPD) anode having dense structure suppressed carbon deposition and exhibited a stable cell operation in SOFC using dry CH4.