Assessment of Acute Mountain Sickness: Comparing the Chinese AMS Score to the Lake Louise Score.

Wu, Yu, Wenqi Zhao, Bao Liu, Jianyang Zhang, Zhifeng Zhong, Simin Zhou, Jiaxin Xie, Yuqi Gao, Peng Li, and Jian Chen. Assessment of Acute Mountain Sickness: Comparing the Chinese Ams Score to the Lake Louise Score. High Alt Med Biol 00:000-000, 2024. Objective: To compare the ability of the Chinese AMS Score (CAS) to detect acute mountain sickness (AMS) using the 2018 version of the Lake Louise Score (LLS) as reference. Methods: After flying from Chengdu (altitude: 500 m) to Lhasa (3,658 m), 2,486 young men completed a questionnaire. The questionnaire contained LLS and CAS items. An LLS ≥3 and/or a CAS ≥cutoff were used as the criteria for AMS. Hierarchical cluster analysis and two-step cluster analysis were used to investigate relationships between the symptoms. Results: AMS incidence rates were 33.8% (n = 840) with the LLS and 59.3% (n = 1,473) with the CAS (χ2 = 872.5, p < 0.001). The LLS and CAS had a linear relationship (orthogonal regression, Pearson r = 0.91, p < 0.001). With the LLS as the standard, the CAS had high diagnostic accuracy (area under the curve = 0.95, 95% confidence interval: 0.94-0.96). However, with the CAS, 25.5% (n = 633) more participants were labeled as having AMS than with the LLS (false positives). Two clusters were identified: one with headache only (419 participants, 66.2%) and one without headache but with other symptoms (214 participants, 33.8%). Reducing the weight of headache in the CAS allowed to align CAS and LLS. Conclusion: In comparison to the LLS, the CAS has a sensitivity close to 100% but lacks specificity given the high rate of false positives. The different weight of headaches may be the main reason for the discrepancy.

MOF-based Ag NPs/Co3O4 nanozyme for colorimetric detection of thiophanate-methyl based on analyte-enhanced sensing mechanism.

Silver nanoparticles supported on metal-organic framework (ZIF-67)-derived Co3O4 nanostructures (Ag NPs/Co3O4) were synthesized via a facile in situ reduction strategy. The resulting materials exhibited pH-switchable peroxidase/catalase-like catalytic activity. Ag NP doping greatly enhanced the catalytic activity of Ag NPs/Co3O4 towards 3,3',5,5'-tetramethylbenzidine (TMB) oxidation and H2O2 decomposition which were 59 times (A652 of oxTMB) and 3 times (A240 of H2O2) higher than that of ZIF-67, respectively. Excitingly, thiophanate-methyl (TM) further enhanced the peroxidase-like activity of Ag NPs/Co3O4 nanozyme due to the formation of Ag(I) species in TM-Ag NPs/Co3O4 and generation of more radicals resulting from strong interaction between Ag NPs and TM. The TM-Ag NPs/Co3O4 nanozyme exhibited lower Km and higher Vmax values towards H2O2 when compared with Ag NPs/Co3O4 nanozyme. A simple, bioelement-free colorimetric TM detection method based on Ag NPs/Co3O4 nanozyme via analyte-enhanced sensing strategy was successfully established with high sensitivity and selectivity. Our study demonstrated that hybrid noble metal NPs/MOF-based nanozyme can be a class of promising artificial nanozyme in environmental and food safety applications.

Semantic Consistent Embedding for Domain Adaptive Zero-Shot Learning.

Unsupervised domain adaptation has limitations when encountering label discrepancy between the source and target domains. While open-set domain adaptation approaches can address situations when the target domain has additional categories, these methods can only detect them but not further classify them. In this paper, we focus on a more challenging setting dubbed Domain Adaptive Zero-Shot Learning (DAZSL), which uses semantic embeddings of class tags as the bridge between seen and unseen classes to learn the classifier for recognizing all categories in the target domain when only the supervision of seen categories in the source domain is available. The main challenge of DAZSL is to perform knowledge transfer across categories and domain styles simultaneously. To this end, we propose a novel end-to-end learning mechanism dubbed Three-way Semantic Consistent Embedding (TSCE) to embed the source domain, target domain, and semantic space into a shared space. Specifically, TSCE learns domain-irrelevant categorical prototypes from the semantic embedding of class tags and uses them as the pivots of the shared space. The source domain features are aligned with the prototypes via their supervised information. On the other hand, the mutual information maximization mechanism is introduced to push the target domain features and prototypes towards each other. By this way, our approach can align domain differences between source and target images, as well as promote knowledge transfer towards unseen classes. Moreover, as there is no supervision in the target domain, the shared space may suffer from the catastrophic forgetting problem. Hence, we further propose a ranking-based embedding alignment mechanism to maintain the consistency between the semantic space and the shared space. Experimental results on both I2AwA and I2WebV clearly validate the effectiveness of our method. Code is available at https://github.com/tiggers23/TSCE-Domain-Adaptive-Zero-Shot-Learning.

Enhanced BPGM/2,3-DPG pathway activity suppresses glycolysis in hypoxic astrocytes via FIH-1 and TET2.

OBJECTIVE: Bisphosphoglycerate mutase (BPGM) is expressed in human erythrocytes and responsible for the production of 2,3-bisphosphoglycerate (2,3-DPG). However, the expression and role of BPGM in other cells have not been reported. In this work, we found that BPGM was significantly upregulated in astrocytes upon acute hypoxia, and the role of this phenomenon will be clarified in the following report. METHODS: The mRNA and protein expression levels of BPGM and the content of 2,3-DPG with hypoxia treatment were determined in vitro and in vivo. Furthermore, glycolysis was evaluated upon in hypoxic astrocytes with BPGM knockdown and in normoxic astrocytes with BPGM overexpression or 2,3-DPG treatment. To investigate the mechanism by which BPGM/2,3-DPG regulated glycolysis in hypoxic astrocytes, we detected the expression of HIF-1α, FIH-1 and TET2 with silencing or overexpression of BPGM and 2,3-DPG treatment. RESULTS: The expression of glycolytic genes and the capacity of lactate markedly increased with 6 h, 12 h, 24 h, 36 h and 48 h 1 % O2 hypoxic treatment in astrocytes. The expression of BPGM was upregulated, and the production of 2,3-DPG was accelerated upon hypoxia. Moreover, when BPGM expression was knocked down, glycolysis was promoted in HEB cells. However, overexpression of BPGM and addition of 2,3-DPG to the cellular medium in normoxic cells could downregulate glycolytic genes. Furthermore, HIF-1α and TET2 exhibited higher expression levels and FIH-1 showed a lower expression level upon BPGM silencing, while these changes were reversed under BPGM overexpression and 2,3-DPG treatment. CONCLUSIONS: Our study revealed that the BPGM/2,3-DPG pathway presented a suppressive effect on glycolysis in hypoxic astrocytes by negatively regulating HIF-1α and TET2.

Diversity in rhizospheric microbial communities in tea varieties at different locations and tapping potential beneficial microorganisms.

Soil microenvironments and plant varieties could largely affect rhizosphere microbial community structure and functions. However, their specific effects on the tea rhizosphere microbial community are yet not clear. Beneficial microorganisms are important groups of microbial communities that hold ecological functionalities by playing critical roles in plant disease resistance, and environmental stress tolerance. Longjing43 and Zhongcha108 are two widely planted tea varieties in China. Although Zhongcha108 shows higher disease resistance than Longjing43, the potential role of beneficial tea rhizosphere microbes in disease resistance is largely unknown. In this study, the structure and function of rhizosphere microbial communities of these two tea varieties were compared by using the Illumina MiSeq sequencing (16S rRNA gene and ITS) technologies. Rhizosphere soil was collected from four independent tea gardens distributed at two locations in Hangzhou and Shengzhou cities in eastern China, Longjing43 and Zhongcha108 are planted at both locations in separate gardens. Significant differences in soil physicochemical properties as demonstrated by ANOVA and PCA, and distinct rhizosphere microbial communities by multiple-biotech analyses (PCoA, LEfSe, Co-occurrence network analyses) between both locations and tea varieties (p < 0.01) were found. Functions of bacteria were annotated by the FAPROTAX database, and a higher abundance of Nitrososphaeraceae relating to soil ecological function was found in rhizosphere soil in Hangzhou. LDA effect size showed that the abundance of arbuscular mycorrhizal fungi (AMF) was higher in Zhongcha108 than that in Longjing43. Field experiments further confirmed that the colonization rate of AMF was higher in Zhongcha108. This finding testified that AMF could be the major beneficial tea rhizosphere microbes that potentially function in enhanced disease resistance. Overall, our results confirmed that locations affected the microbial community greater than that of tea varieties, and fungi might be more sensitive to the change in microenvironments. Furthermore, we found several beneficial microorganisms, which are of great significance in improving the ecological environment of tea gardens and the disease resistance of tea plants. These beneficial microbial communities may also help to further reveal the mechanism of disease resistance in tea and potentially be useful for mitigating climate change-associated challenges to tea gardens in the future.

Simple and sensitive determination of sulfites in Chinese herbal teas by ultrahigh-performance liquid chromatography tandem mass spectrometry.

Sulfites are used widely in food and beverage production to prevent browning or oxidation. However, the overingestion of sulfites is harmful to human health and may cause medical complications. Chinese herbal teas have been widely consumed for centuries. However, sulfite levels in Chinese herbal teas are rarely investigated and reported. Here, we present a simple, sensitive, and quantitative method to determine sulfites in Chinese herbal teas using ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) coupled with dispersive solid phase extraction. The method utilized a SeQuant ZIC-HILIC column for separation, and the optimal gradient eluents consisted of acetonitrile and aqueous solution with 0.1% acetic acid and 10 mM ammonium acetate. Porous chitosan/partially reduced graphene oxide/diatomite (CS/prGO/DM) composites were used as efficient dispersive solid phase extraction adsorbents for sample preparation. Several parameters were investigated during the extraction process, including sample-to-extraction solvent volume ratios, the extraction procedure and dosage of the adsorbent. Under the optimum conditions, the developed method gave a good determination coefficient (r2 > 0.99), low detection limits (0.51-12.1 µg kg-1) and high recoveries in the range of 83.8-102.7% at different spiked levels. The method has the great advantages of being time saving, good reproducibility and much lower detection limits when compared to titration methods. The method was further applied to analyze real herbal tea samples collected from the local market, demonstrating that our developed method is robust and useful for determining sulfites in practical application.

Influence of 3D laparoscopic surgery on surgeon's visual pattern and mental workload.

Previous studies have found that surgeons perform better in three-dimensional (3D) surgery than in two-dimensional (2D) surgery. However, no comparative studies have revealed the impact of 3D laparoscopic surgery on the surgeon's vision. To explore the effect of laparoscopic surgeons' depth perception during 3D laparoscopic surgery, 10 participants were recruited and performed 4 sets comparative simulated laparoscopic procedures in a virtual simulator, and eye movement signals were acquired, which were used to characteristics the visual differences. Fixation rate and saccade speed were used to characterise the influence of moderating variables for visual characteristics. The results from the data showed significant differences in eye movement behaviour. Compared with 2D laparoscopic surgery, surgeons have more average fixation rate (p-values = 0.001, 0.000, 0.003 and 0.015, respectively) and faster saccade speed (p-values = 0.037, 0.003, 0.073 and 0.105, respectively) in 3D laparoscopic surgery. The results of this study showed that surgeons had more efficient visual search in 3D laparoscopic surgery. At the same time, the results also indicated that surgeon's mental workload in 3D laparoscopic surgery was low. The relevant conclusions of this paper revealed the advantages of 3D laparoscopic surgery through visual efficiency.

DL-3-n-butylphthalide improved physical and learning and memory performance of rodents exposed to acute and chronic hypobaric hypoxia.

BACKGROUND: Studies have revealed the protective effect of DL-3-n-butylphthalide (NBP) against diseases associated with ischemic hypoxia. However, the role of NBP in animals with hypobaric hypoxia has not been elucidated. This study investigated the effects of NBP on rodents with acute and chronic hypobaric hypoxia. METHODS: Sprague-Dwaley rats and Kunming mice administered with NBP (0, 60, 120, and 240 mg/kg for rats and 0, 90, 180, and 360 mg/kg for mice) were placed in a hypobaric hypoxia chamber at 10,000 m and the survival percentages at 30 min were determined. Then, the time and distance to exhaustion of drug-treated rodents were evaluated during treadmill running and motor-driven wheel-track treadmill experiments, conducted at 5800 m for 3 days or 20 days, to evaluate changes in physical functions. The frequency of active escapes and duration of active escapes were also determined for rats in a shuttle-box experiment, conducted at 5800 m for 6 days or 27 days, to evaluate changes in learning and memory function. ATP levels were measured in the gastrocnemius muscle and malonaldehyde (MDA), superoxide dismutase (SOD), hydrogen peroxide (H2O2), glutathione peroxidase (GSH-Px), and lactate were detected in sera of rats, and routine blood tests were also performed. RESULTS: Survival analysis at 10,000 m indicated NBP could improve hypoxia tolerance ability. The time and distance to exhaustion for mice (NBP, 90 mg/kg) and time to exhaustion for rats (NBP, 120 and 240 mg/kg) significantly increased under conditions of acute hypoxia compared with control group. NBP treatment also significantly increased the time to exhaustion for rats when exposed to chronic hypoxia. Moreover, 240 mg/kg NBP significantly increased the frequency of active escapes under conditions of acute hypoxia. Furthermore, the levels of MDA and H2O2 decreased but those of SOD and GSH-Px in the sera of rats increased under conditions of acute and chronic hypoxia. Additionally, ATP levels in the gastrocnemius muscle significantly increased, while lactate levels in sera significantly decreased. CONCLUSION: NBP improved physical and learning and memory functions in rodents exposed to acute or chronic hypobaric hypoxia by increasing their anti-oxidative capacity and energy supply.

Critical transmission paths and nodes of carbon emissions in electricity supply chain.

As the largest contributor to production-based emissions, electricity generation sector has led to huge carbon emission transmissions. This is the first attempt to explore the latest features of carbon emission transmissions from electricity sector to the final domestic consumption of China in 2002-2015, combining MRIO-based Structural Path Analysis and transmission-based emission method. Results show that: (1) Although inter-provincial transmissions are increasing significantly, emission transmissions within intra-provincial trading are dominated. (2) 30 provinces are classified into two types, i.e., consumption centers and production centers. Both the inter-provincial transmission paths in consumption centers and production centers show the grid-level agglomeration and provincial heterogeneity. The inflow paths in consumption centers are mainly sourced from the production of Eastern China and South China, while the outflow paths for production centers are caused by the consumption in Central China, Guangdong and Jiangsu. Inter-provincial linkages are intensified and perform the feature of territorial propinquity. (3) Both intra-grid and inter-grid transmission nodes show an agglomeration trend of "electricity sector < intermediate sectors < electricity sector < consumption". These intermediate sectors include manufacture sectors, energy-intensive sectors and service sector. This paper provides policy implications on promoting low-carbon electricity cooperation across provinces and managing intermediate transmissions along supply chain.

Impact Toughness Anisotropy of TA31 Titanium Alloy Cylindrical Shell after Ring Rolling.

The impact toughness of a TA31 titanium alloy cylindrical shell was investigated systemically after ring rolling. The impact toughness of specimens with different notch orientations shows obvious anisotropy. The microstructure of the cylindrical shell and the impact fracture were characterized by an optical microscope and scanning electron microscope. The results show that cracks are easier to propagate in the equiaxed α phase than the elongated α phase. This is because the expanding cracking path in the equiaxed α phase is shorter than that in the elongated α phase, and thereby the cracks are easier to propagate in the equiaxed α phase than the elongated α phase. More specifically, the α phase on the RD-TD plane was obviously isotropic, which makes it easy for the cracks to propagate along α grains in the same direction. However, the α phase on the RD-ND plane has a layered characteristic, and the direction of the α phase varies from layer to layer, thus it requires higher energy for cracks to propagate across this layered α phase. Therefore, the cracks propagating in the same α phase orientation take easier than that in the layered α phase, so it has lower impact toughness.

VisTCR: An Interactive Software for T Cell Repertoire Sequencing Data Analysis.

Recent progress in high throughput sequencing technologies has provided an opportunity to probe T cell receptor (TCR) repertoire, bringing about an explosion of TCR sequencing data and analysis tools. For easier and more heuristic analysis TCR sequencing data, we developed a client-based HTML program (VisTCR). It has a data storage module and a data analysis module that integrate multiple cutting-edge analysis algorithms in a hierarchical fashion. Researchers can group and re-group samples for different analysis purposes by customized "Experiment Design File." Moreover, the VisTCR provides a user-friendly interactive interface, by all the TCR analysis methods and visualization results can be accessed and saved as tables or graphs in the process of analysis. The source code is freely available at https://github.com/qingshanni/VisTCR.

Molecular basis for the function of the αß heterodimer of human NAD-dependent isocitrate dehydrogenase.

Mammalian mitochondrial NAD-dependent isocitrate dehydrogenase (NAD-IDH) catalyzes the decarboxylation of isocitrate into α-ketoglutarate in the tricarboxylic acid cycle. It exists as the α2ßγ heterotetramer composed of the αß and αγ heterodimers. Different from the αγ heterodimer that can be allosterically activated by CIT and ADP, the αß heterodimer cannot be allosterically regulated by the activators; however, the molecular mechanism is unclear. We report here the crystal structures of the αß heterodimer of human NAD-IDH with the α subunit in apo form and in Ca2+-bound, NAD-bound, and NADH-bound forms. Structural analyses and comparisons reveal that the αß heterodimer has a similar yet more compact overall structure compared with the αγ heterodimer and contains a pseudo-allosteric site that is structurally different from the allosteric site. In particular, the ß3-α3 and ß12-α8 loops of the ß subunit at the pseudo-allosteric site adopt significantly different conformations from those of the γ subunit at the allosteric site and hence impede the binding of the activators, explaining why the αß heterodimer cannot be allosterically regulated by the activators. The structural data also show that NADH can compete with NAD to bind to the active site and inhibits the activity of the αß heterodimer. These findings together with the biochemical data reveal the molecular basis for the function of the αß heterodimer of human NAD-IDH.

The Role of Salivary miR-134-3p and miR-15b-5p as Potential Non-invasive Predictors for Not Developing Acute Mountain Sickness.

BACKGROUND: Acute mountain sickness (AMS) is a crucial public health problem for high altitude travelers. Discriminating individuals who are not developing (AMS resistance, AMS-) from developing AMS (AMS susceptibility, AMS+) at baseline would be vital for disease prevention. Salivary microRNAs (miRNAs) have emerged as promising non-invasive biomarkers for various diseases. Thus, the aim of our study was to identify the potential roles of salivary miRNAs in identifying AMS- individuals pre-exposed to high altitude. Moreover, as hypoxia is the triggering factor for AMS, present study also explored the association between cerebral tissue oxygenation indices (TOI) and AMS development after exposed to high altitude, which was the complementary aim. METHODS: In this study, 124 healthy men were recruited, and were exposed at simulated high altitude of 4,500 m. Salivary miR-134-3p and miR-15b-5p were measured at baseline (200 m). AMS was diagnosed based on Lake Louise Scoring System at 4,500 m. The measurements of physiological parameters were recorded at both the altitudes. RESULTS: Salivary miR-134-3p and miR-15b-5p were significantly up-regulated in AMS- individuals as compared to the AMS+ (p < 0.05). In addition, the combination of these miRNAs generated a high power for discriminating the AMS- from AMS+ at baseline (AUC: 0.811, 95% CI: 0.731-0.876, p < 0.001). Moreover, the value of cerebral TOIs at 4,500 m were significantly higher in AMS- individuals, compared to AMS+ (p < 0.01). CONCLUSION: Our study reveals for the first time that salivary miR-134-3p and miR-15b-5p can be used as non-invasive biomarkers for predicting AMS- individuals pre-exposed to high altitude.

Subjective and Objective Quantification of the Effect of Distraction on Physician's Workload and Performance During Simulated Laparoscopic Surgery.

BACKGROUND Distracting interference cognitive tasks place undeniable pressure on the minds of people who need high precision and attention during the tasks, such as those tasks performed during surgery; these tasks might affect current surgical procedures. We measured the effect of additional cognitive tasks on the mental load of the physician by measuring the mean change in pupil size, blink rate, and subjective assessment during surgery. MATERIAL AND METHODS We recruited 24 participants with different levels of laparoscopic surgery to perform a complete appendectomy using a standardized virtual reality laparoscopic surgery simulator. The participants then performed the cognitive task (arithmetic problem), after that they performed an appendectomy surgery task while completing the cognitive task on the simulator. All participants wore trackers to monitor pupil size and blink rate during surgery and the cognitive task. The National Aeronautics and Space Administration (NASA) Task Load Index (TLX) score also recorded performance parameters during the surgical mission. RESULTS The double-task pupil size and the blink rate were significantly increased compared to the single-task observation, and the associated increase in psychological load might have been affected by surgical performance, and the performance parameters were also statistically significant. However, for the aforementioned parameters, experienced surgeons had some differences compared with inexperienced surgeons, but these differences did not reach statistical significance. CONCLUSIONS Distracted cognitive task stimulation in the operating room can increase the surgeon's psychological burden while also affecting their operational skills, thereby threatening patient safety; reduced cognitive costs might be obtained by improving or managing cognitive deficits.

An improved formula for standard hypoxia tolerance time (STT) to evaluate hypoxic tolerance in mice.

BACKGROUND: Hypoxia is a primary cause of mountain sickness and a common pathological condition in patients with heart failure, shock, stroke, and chronic obstructive pulmonary disease (COPD). Thus far, little advancement in countering hypoxic damage has been achieved, and one of the main reasons is the absence of an ideal algorithm or calculation method to normalize hypoxia tolerance scores when evaluating an animal model. In this study, we improved a traditional calculation formula for assessment of hypoxia tolerance. METHODS: We used a sealed bottle model in which the oxygen is gradually consumed by a mouse inside. To evaluate the hypoxia tolerance of mice, the survival time (ST) of the mouse is recorded and was used to calculate standard hypoxia tolerance time (STT) and adjusted standard hypoxia tolerance time (ASTT). Mice administered with methazolamide and saline were used as positive and negative controls, respectively. RESULTS: Since mice were grouped according to either body weight (BW) or bottle volume, we found a strongly negative correlation between STT and BW instead of between STT and bottle volume, suggesting that different BWs could cause false positive or negative errors in the STT results. Furthermore, both false positive and negative errors could be rectified when ASTT was used as the evaluation index. Screening for anti-hypoxic medicines by using mice as the experimental subjects would provide more credible results with the improved ASTT method than with the STT method. CONCLUSION: ASTT could be a better index than STT for the evaluation of hypoxia tolerance abilities as it could eliminate the impact of animal BW.

Ergonomic Assessment of the Mental Workload Confronted by Surgeons during Laparoscopic Surgery.

Although the mental workload confronted by laparoscopic surgeons is rather high, there is presently no reliable, established method for evaluating this workload. In the present study, four evaluation indices of eye movement metrics were applied to evaluate surgeons' mental workload. Correlations between these indices and National Aeronautics and Space Administration Task Load Index (NASA-TLX) scores were also explored. Sixteen participants were recruited to complete four laparoscopic procedures. Eye movement was recorded during the tasks, and NASA-TLX scales were also introduced for subjective evaluation. The data were analyzed using R 3.3.2. Significant differences in the mental workload of each task were observed. Statistically significant correlations between mean pupil diameter change and NASA-TLX scores were also observed. The correlation coefficients were 0.763, 0.675, 0.405, and 0.547, and the P values correspondingly were 0.001, 0.004, 0.12, and 0.028, respectively. The results clarify that the mental workload of laparoscopic surgeons is dependent on the specific demands of the operation. Appropriate objective physiological indices can be used to identify the mental workload state of the surgeon.

Author Correction: Correlative Evaluation of Mental and Physical Workload of Laparoscopic Surgeons Based on Surface Electromyography and Eye-tracking Signals.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Quantitative Evaluations of the Effects of Noise on Mental Workloads Based on Pupil Dilation during Laparoscopic Surgery.

Noise can exert undeniable pressure on human minds, especially during tasks that require high precision and attention, such as those performed during surgery. To investigate whether auditory stimuli increases mental loads during laparoscopic surgery, we examined the effects of operating room (OR) noises and music by measuring mean changes in pupil sizes and subjectively assessing performances during surgery. We recruited 24 subjects with varying laparoscopic surgery experience levels to perform complete appendectomy using a laparoscopic simulator. Wearable eye trackers were worn by all subjects to monitor pupil sizes during surgery, and surgical tasks were performed under conditions of silence, background OR noise, and music. National Aeronautics and Space Administration-Task Load Index scores and performance parameters were also recorded during surgical tasks. Noise distractions were associated with significant increases in pupil sizes compared with those observed in silence, and the related increases in mental loads may have affected surgical performance. However, more experienced operators had smaller changes in pupil sizes because of auditory disturbances than moderately experienced surgeons. Noise stimulation in the OR increases surgeon's mental workload and performance. Auditory regulation of the OR may be better standardized using data from studies of the effects of acoustic stimulation in the OR, and mental stresses during surgery could be considered in a more humane manner. Further investigations are necessary to determine the cognitive consequences of various auditory stimuli.

Correlative Evaluation of Mental and Physical Workload of Laparoscopic Surgeons Based on Surface Electromyography and Eye-tracking Signals.

Surgeons' mental and physical workloads are major focuses of operating room (OR) ergonomics, and studies on this topic have generally focused on either mental workload or physical workload, ignoring the interaction between them. Previous studies have shown that physically demanding work may affect mental performance and may be accompanied by impaired mental processing and decreased performance. In this study, 14 participants were recruited to perform laparoscopic cholecystectomy (LC) procedures in a virtual simulator. Surface electromyography (sEMG) signals of the bilateral trapezius, bicipital, brachioradialis and flexor carpi ulnaris (FCU) muscles and eye-tracking signals were acquired during the experiment. The results showed that the least square means of muscle activity during the LC phases of surgery in an all-participants mixed effects model were 0.79, 0.81, and 0.98, respectively. The observed muscle activities in the different phases exhibited some similarity, while marked differences were found between the forearm bilateral muscles. Regarding mental workload, significant differences were observed in pupil dilation between the three phases of laparoscopic surgery. The mental and physical workloads of laparoscopic surgeons do not appear to be generally correlated, although a few significant negative correlations were found. This result further indicates that mental fatigue does markedly interfere with surgeons' operating movements.

Profiling elements in Puerh tea from Yunnan province, China.

Puerh tea, as the most representative Chinese dark tea, has attracted global interest in recent years. Profiling the levels of metal elements in Puerh tea is very important since its presence is related to human health. In this study, 41 elements in 98 Puerh tea samples from Yunnan province, China including Puerh raw tea and Puerh ripe tea were evaluated by microwave digestion combined with inductively coupled plasma mass spectrometry . The content of toxic elements, essential elements and rare earth elements of Puerh tea from different regions was discussed in detail. The concentrations of Ba, Cr, As, Pb, Bi, Fe, Zn, V, Mn, Be, Ag and Tl showed significant differences (p < 0.05) by ANOVA analysis. Principal component analysis and linear discriminant analysis were used to describe the relationship of Puerh tea from different regions. This study provided a comprehensive database for Puerh tea quality control and intake risk assessment.