Streptomyces camelliae sp. nov., isolated from rhizosphere soil of Camellia oleifera Abel.

A novel actinobacterium strain, designated HUAS 2-6 T, was isolated from the rhizosphere soil of Camellia oleifera Abel collected from Taoyuan County, Northwestern Hunan Province, South China. This strain was subjected to a polyphasic taxonomic study. Strain HUAS 2-6 T is characterized by morphology typical of members of the genus Streptomyces, with deep purplish vinaceous aerial mycelia and deep dull lavender substrate mycelia. Strain HUAS 2-6 T, based on the full-length 16S rRNA gene sequence analysis, exhibited the highest similarities to S. puniciscabiei S77T (99.31%), S. filipinensis NBRC 12860 T (99.10%), S. yaanensis CGMCC 4.7035 T (99.09%), S. fodineus TW1S1T (99.08%), S. broussonetiae CICC 24819 T (98.76%), S. achromogenes JCM 4121 T (98.69%), S. barringtoniae JA03T (98.69%), and less than 98.70% with other validly species. In phylogenomic tree, strain HUAS 2-6 T was clustered together with S. broussonetiae CICC 24819 T, suggesting that they were closely related to each other. However, average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) between them were much less than the species cutoff values (ANI 96.7% and dDDH 70%). Moreover, in phenotypic and chemotaxonomic characteristics, strain HUAS 2-6 T is distinct from S. broussonetiae CICC 24819 T. On the basis of the polyphasic data, strain HUAS 2-6 T is proposed to represent a novel species, Streptomyces camelliae sp. nov. (= MCCC 1K04729T = JCM 35918 T).

Effect modification of time spent outdoors on the association between early childhood overweight and myopia: a one-year follow-up study.

BACKGROUND: This study examined the moderating role of outdoor time on the relationship between overweight and myopia. METHODS: The data for this study was obtained from a prospective study in Shanghai, where non-myopic children wore wristwear and were followed up for 1 year. Eye examinations were performed at each visit. The modification effect was assessed on the additive scale using multivariable logistic regression, and relative excess risk due to interaction was used to calculate the modification effect. RESULTS: A total of 4683 non-myopic children were included with 32.20% being overweight at baseline. Following a 1-year period, 17.42% of children had myopia. When compared to those who spent <90 minutes outdoors, children who spent >120 had a relative risk of myopia onset that was reduced to 0.61. As time spent outdoors decreased, more risks of myopia onset were identified among overweight children than among normal children, the modification effect on the additive scale was -0.007, with ~70% of this effect attributed to the modifying influence of outdoor time. CONCLUSIONS: Increasing outdoor time can reduce myopia more among overweight children than normal. Future interventions should focus on outdoor activities among overweight children to reduce myopia risks.

Analysis based on Monte Carlo simulation: How effective is tigecycline in routine antimicrobial therapy?

OBJECTIVE: This paper aims to assess the efficacy of tigecycline in the treatment of several different infections from a pharmacokinetic/pharmacodynamic (PK/PD) perspective. MATERIALS AND METHODS: The minimum inhibitory concentration (MIC) test strip test was used to determine the MICs of clinical isolates of tigecycline. A 5,000-subjects simulation was performed by Crystal Ball software to calculate the probability of achieving the required PK/PD exposure. RESULTS: The use of standard tigecycline dosing is predicted to have a good clinical outcome for patients suffering from complicated skin and skin structure infection (cSSSI) with MICs ≤ 0.25 mg×L-1, patients suffering from complicated intra-abdominal infection (cIAI) with MICs ≤ 1 mg×L-1, and patients suffering from hospital-acquired pneumonia (HAP) with MICs ≤ 0.5 mg×L-1. Generally, Gram-positive bacteria are highly sensitive to tigecycline, while Gram-negative bacteria are less sensitive: for patients with HAP and cIAI, the tolerable outcome was achieved using the standard regimen for most Gram-negative pathogens; the desired outcomes could be obtained for the increased-dose treatment; with increasing dose (100 mg every 12 hours), the average cumulative fractions of response (CFRs) markedly increased from 38.18 to 56.21% for cSSSI patients. When tigecycline, a standard regimen, was used to treat carbapenem-resistant Klebsiella pneumoniae (CRKP) and carbapenem-resistant Enterobacter spp. (CRE) infections, the cumulative response scores were 4.96 - 66.39% and 13.14 - 95.18%, respectively, and the CFRs of the increased dose also increased correspondingly. CONCLUSION: Currently, the standard dose of tigecycline is feasible in the treatment of common bacterial infections, and PK/PD indexes are needed to optimize the regimens for refractory carbapenem-resistant bacterial infections.

Safety and Efficacy of Tigecycline in Intensive Care Unit Patients Based on Therapeutic Drug Monitoring.

OBJECTIVE: Tigecycline exerts significant beneficial effects against drug-resistant bacterial infections. The largely empirical medications used in clinical practice are often associated with wide individual differences in efficacy and safety. We investigated the associations between the pharmacokinetics of tigecycline and its efficacy and safety in intensive care unit (ICU) patients, with the aim of facilitating clinical applications of tigecycline. METHODS: ICU patients who were prescribed tigecycline in a hospital setting were prospectively included. Factors related to the clinical efficacy and safety of tigecycline were assessed by univariate and multivariate analyses. RESULTS: This study included 45 patients, from whom a total of 63 blood samples were collected to determine steady-state trough plasma concentrations (Cmin) of tigecycline. The Cmin of tigecycline was 417.1 ± 263.8 ng/mL (mean ± SD). The multivariate analysis showed that the APACHE II scores [odds ratio (OR) = 0.874, 95% confidence interval (CI) = 0.733-0.901, P = 0.048] were significantly correlated with the efficacy of tigecycline, whereas there was no correlation between Cmin of tigecycline and efficacy. In safety, the risk factors significantly associated with hepatotoxicity were sex (OR = 0.562, 95% CI = 0.191-0.774, P = 0.023), APACHE II score (OR = 1.061, 95% CI = 1.039-1.392, P = 0.045), and Cmin (OR = 1.210, 95% CI = 1.014-1.336, P = 0.008). The optimal cut-off for hepatotoxicity in ICU patients treated with tigecycline was 474.8 ng/mL. CONCLUSIONS: There was considerable variability in the Cmin of tigecycline among the ICU patients in this study and it is at risk of high exposure in women. Cmin can be a useful predictor of hepatotoxicity with a cut-off of 474.8 ng/mL.

Facile Generation of Polymer-Alloy Hybrid Layers for Dendrite-Free Lithium-Metal Anodes with Improved Moisture Stability.

Lithium-metal anodes are recognized as the most promising next-generation anodes for high-energy-storage batteries. However, lithium dendrites lead to irreversible capacity decay in lithium-metal batteries (LMBs). Besides, the strict assembly-environment conditions of LMBs are regarded as a challenge for practical applications. In this study, a workable lithium-metal anode with an artificial hybrid layer composed of a polymer and an alloy was designed and prepared by a simple chemical-modification strategy. Treated lithium anodes remained dendrite-free for over 1000 h in a Li-Li symmetric cell and exhibited outstanding cycle performance in high-areal-loading Li-S and Li-LiFePO4 full cells. Moreover, the treated lithium showed improved moisture stability that benefits from the hydrophobicity of the polymer, thus retaining good electrochemical performance after exposure to humid air.

Principal dynamic mode analysis of neural mass model for the identification of epileptic states.

The detection of epileptic seizures in Electroencephalography (EEG) signals is significant for the diagnosis and treatment of epilepsy. In this paper, in order to obtain characteristics of various epileptiform EEGs that may differentiate different states of epilepsy, the concept of Principal Dynamic Modes (PDMs) was incorporated to an autoregressive model framework. First, the neural mass model was used to simulate the required intracerebral EEG signals of various epileptiform activities. Then, the PDMs estimated from the nonlinear autoregressive Volterra models, as well as the corresponding Associated Nonlinear Functions (ANFs), were used for the modeling of epileptic EEGs. The efficient PDM modeling approach provided physiological interpretation of the system. Results revealed that the ANFs of the 1st and 2nd PDMs for the auto-regressive input exhibited evident differences among different states of epilepsy, where the ANFs of the sustained spikes' activity encountered at seizure onset or during a seizure were the most differentiable from that of the normal state. Therefore, the ANFs may be characteristics for the classification of normal and seizure states in the clinical detection of seizures and thus provide assistance for the diagnosis of epilepsy.

Impact of diurnal temperature range on human health: a systematic review.

Increasing epidemiological studies have shown that a rapid temperature change within 1 day is an independent risk factor for human health. This paper aimed to systematically review the epidemiological evidence on the relationship between diurnal temperature range (DTR) and human health and to propose future research directions. A literature search was conducted in October 2013 using the databases including PubMed, ScienceDirect, and EBSCO. Empirical studies regarding the relationship between DTR and mortality and morbidity were included. Twenty-five relevant studies were identified, among which, 11 investigated the relationship between DTR and mortality and 14 examined the impact of DTR on morbidity. The majority of existing studies reported that DTR was significantly associated with mortality and morbidity, particularly for cardiovascular and respiratory diseases. Notably, compared with adults, the elderly and children were more vulnerable to DTR effects. However, there were some inconsistencies regarding the susceptible groups, lag time, and threshold of DTR. The impact of DTR on human health may be confounded or modified by season, socioeconomic, and educational status. Further research is needed to further confirm the adverse effects of DTR in different geographical locations; examine the effects of DTR on the health of children aged one or under; explore extreme DTR effects on human health; analyze the difference of DTR effects on human health in different locations and the modified effects of potential confounding factors; and develop detailed preventive measures against large DTR, particularly for susceptible groups.

Effect of simultaneous variation in temperature and ammonia concentration on percent fertilization and hatching in Crassostrea ariakensis.

The combined effects of temperature and ammonia concentration on the percent fertilization and percent hatching in Crassostrea ariakensis were examined under laboratory conditions using the central composite design and response surface methodology. The results indicated: (1) The linear effects of temperature and ammonia concentration on the percent fertilization were significant (P<0.05), and the quadratic effects were highly significant (P<0.01). The interactive effect between temperature and ammonia concentration on the percent fertilization was not significant (P>0.05). (2) The linear effect of temperature on the percent hatching was highly significant (P<0.01), and that of ammonia concentration was nonsignificant (P>0.05). The quadratic effects of temperature and ammonia concentration on the percent hatching were highly significant (P<0.01). The interaction on the percent hatching was not significant (P>0.05). Temperature was more important than ammonia in influencing the fertilization and hatching in C. ariakensis. (3) The model equations of the percent fertilization and hatching towards temperature and ammonia concentration were established, with the coefficients of determination R(2)=99.4% and 99.76%, respectively. Through the lack-of-fit test, these models were of great adequacy. The predictive coefficients of determination for the two model equations were as high as 94.6% and 98.03%, respectively, showing that they could be used for practical projection. (4) Via the statistical simultaneous optimization technique, the optimal factor level combination, i.e., 25°C/0.038mgmL(-1), was derived, at which the greatest percent fertilization 95.25% and hatching 83.26% was achieved, with the desirability being 97.81%. Our results may provide advantageous guidelines for the successful reproduction of C. ariakensis.

Magilock: a reliable control triggering method in multi-channel eye-control systems.

Eye-tracking technology brings a different human-computer interaction experience to users because of its intuitive, natural, and hands-free operation characteristics. Avoiding the Midas touch problem and improving the accuracy of interaction are among the main goals of the research and development of eye-control systems. This study reviews the methods and limitations of research on avoiding the Midas touch problem. For typical control clicking operations with low fault tolerance, such as mode switching and state selection in an eye-control system, this study proposes Magilock, a more reliable control triggering method with a high success rate in multi-channel eye-control systems. Magilock adds a control pre-locked mechanism between the two interactive steps of eye-control channel positioning control and other interactive channel triggering controls in the multi-channel eye-control system. This effectively avoids incorrect control triggering caused by multi-channel coordination disorder and gaze-point drift. This study also conducted ergonomic experiments to explore the lock and unlock times of the control pre-locked mechanism in Magilock. Taking into account the experimental data and subjective evaluation of the participants, we recommend setting the lock time and the unlock time of Magilock to 200 ms.

Transcription factor EgGRP2A regulates EgFATA expression and promotes oleic acid accumulation in oil palm (Elaeis guineensis).

The oil palm (Elaeis guineensis) is emerging as the world's most important and prolific oilseed crop, celebrated for its impressive oil yield. However, the molecular intricacies that govern lipid metabolism and fatty acid accumulation in oil palm fruits remain relatively underexplored. This study reveals a significant correlation between the expression of EgGRP2A, a transcription factor, and the expression of EgFATA in the oil palm. Yeast one-hybrid analysis and electrophoretic mobility shift assays (EMSA) reveal and confirm the binding interactions between EgGRP2A and the promoter region of EgFATA. Subsequent experiments in oil palm protoplasts show that transient overexpression of EgGRP2A leads to a marked upregulation of EgFATA expression. Conversely, downregulation of EgGRP2A in transgenic oil palm embryoids leads to a significant reduction in EgFATA expression. Metabolite profiling in the transgenic embryoids reveals a significant reduction in unsaturated fatty acids, particularly oleic acid. These findings promise profound insights into the regulatory orchestration of EgFATA and the synthesis of fatty acids, particularly oleic acid, in the oil palm. Furthermore, the results lay the foundation for future breeding and genetic improvement efforts aimed at increasing oleic acid content in oil palm varieties.

Intra-operative hydrotubation improves fertility of women with distal tubal occlusion after reproductive surgery.

PURPOSE: Hydrotubation has been considered to be a complimentary procedure to reproductive surgery, usually being conducted after surgery. The objective of this work was to assess the potential value of intra-operative hydrotubation in improving fertility of tubal infertile women. METHODS: 180 tubal infertile women were randomly assigned to one of the three groups: intra-operative hydrotubation (IH), post-operative hydrotubation (PH) or control group. In IH group, the hydrotubation was performed immediately after adhesiolysis during the surgery process, while in PH group it was performed within 3-7 days after the first post-operative menstruation. The incidence of post-operative pelvic infection and average hospitalization length were recorded. The post-operative pregnancy outcomes, including intrauterine pregnancy (IUP) rate and incidence of ectopic pregnancy, were recorded at 2 years follow-up. RESULTS: No significant difference was found among the three groups, either in the incidence of pelvic infection (P = 0.877) or in the average hospitalization length (P = 0.596). At 2 years of follow-up, the rate of IUP in IH group was significantly higher than that in either PH or control group (P = 0.017 and 0.039, respectively), but no difference was observed between PH and control group (P = 0.752). No significant difference in the incidence of ectopic pregnancy was showed among three groups (P = 0.947). CONCLUSIONS: The appropriate use of intra-operative hydrotubation can improve the post-operative IUP rate, serving as a complementary procedure for the surgical treatment of fertility reversal.

A dynamic scheduling method of Earth-observing satellites by employing rolling horizon strategy.

Focused on the dynamic scheduling problem for earth-observing satellites (EOS), an integer programming model is constructed after analyzing the main constraints. The rolling horizon (RH) strategy is proposed according to the independent arriving time and deadline of the imaging tasks. This strategy is designed with a mixed triggering mode composed of periodical triggering and event triggering, and the scheduling horizon is decomposed into a series of static scheduling intervals. By optimizing the scheduling schemes in each interval, the dynamic scheduling of EOS is realized. We also propose three dynamic scheduling algorithms by the combination of the RH strategy and various heuristic algorithms. Finally, the scheduling results of different algorithms are compared and the presented methods in this paper are demonstrated to be efficient by extensive experiments.

Imaging tasks scheduling for high-altitude airship in emergency condition based on energy-aware strategy.

Aiming to the imaging tasks scheduling problem on high-altitude airship in emergency condition, the programming models are constructed by analyzing the main constraints, which take the maximum task benefit and the minimum energy consumption as two optimization objectives. Firstly, the hierarchy architecture is adopted to convert this scheduling problem into three subproblems, that is, the task ranking, value task detecting, and energy conservation optimization. Then, the algorithms are designed for the sub-problems, and the solving results are corresponding to feasible solution, efficient solution, and optimization solution of original problem, respectively. This paper makes detailed introduction to the energy-aware optimization strategy, which can rationally adjust airship's cruising speed based on the distribution of task's deadline, so as to decrease the total energy consumption caused by cruising activities. Finally, the application results and comparison analysis show that the proposed strategy and algorithm are effective and feasible.

Spectral analysis of multiple scattering factors of turbid media for glucose measurement using near-infrared spectroscopy.

Significance: Near-infrared (NIR) diffuse reflectance spectroscopy has been widely used for non-invasive glucose measurement in humans, as glucose can induce a significant and detectable optical signal change in tissue. However, the scattering-dominated glucose spectrum in the range of 1000 to 1700 nm is easily confused with many other scattering factors, such as particle density, particle size, and tissue refractive index. Aim: Our aim is to identify the subtle distinctions between glucose and these factors through theoretical analysis and experimental verification, in order to employ suitable methods for eliminating these interferences, thus increasing the accuracy of non-invasive glucose measurement. Approach: We present a theoretical analysis of the spectra of 1000 to 1700 nm for glucose and some scattering factors, which is then verified by an experiment on a 3% Intralipid solution. Results: We found that both the theoretical and experimental results show that the effective attenuation coefficient of glucose has distinct spectral characteristics, which are distinct from the spectra caused by particle density and refractive index, particularly in the range of 1400 to 1700 nm. Conclusions: Our findings can offer a theoretical foundation for eliminating these interferences in non-invasive glucose measurement, aiding mathematical methods to model appropriately and enhance the accuracy of glucose prediction.

High endothelial venules proportion in tertiary lymphoid structure is a prognostic marker and correlated with anti-tumor immune microenvironment in colorectal cancer.

BACKGROUND: High endothelial venules (HEV) and tertiary lymphoid structures (TLS) are associated with clinical outcomes of patients with colorectal cancer (CRC). However, because HEV are components of TLS, there have been few studies of the role of the HEV proportion in TLS (HEV/TLS). This study investigated the role of the HEV/TLS and its relationship with the tumor immune microenvironment in CRC. METHODS: A retrospective analysis of 203 cases of tissue pathologically diagnosed as CRC after general surgery was performed at the First Affiliated Hospital of Jinan University from January 2014 to July 2017. Paraffin sections were obtained from the paracancerous intestinal mucosal tissues. The area of HEV and TLS and immune cells were detected by immunohistochemistry. We further divided the positive HEV expression group into the high HEV/TLS group and the low HEV/TLS group by the average area of HEV/TLS. After grouping, the data were also analyzed using the chi-square test, Kaplan-Meier method, and univariate and multivariate Cox proportional risk regression analyses. A correlation analysis of the HEV/TLS and immune cells as well as angiogenesis was performed. RESULTS: Patients with a high HEV/TLS in CRC tissue were associated with longer OS, DFS and lower TNM stage. Meanwhile, CRC tissue with a high HEV/TLS showed a greater ability to recruit the CD3+ T cells, CD8+ T cells and M1 macrophages and correlated with less angiogenesis. Conclusively, high HEV/TLS links to the favorable prognosis of CRC patients and correlated with anti-tumor immune microenvironment, which can be a potential biomarker for prognosis of CRC patients. CONCLUSION: A high HEV/TLS is associated with a favorable prognosis for CRC and is correlated with the anti-tumor immune microenvironment. Therefore, it is a potential biomarker of the CRC prognosis.KEY MESSAGESHigh HEV/TLS is associated with a favorable prognosis for CRC.High HEV/TLS correlated with the anti-tumor immune microenvironment of CRC and can serve as a novel prognostic biomarker.

Machine Learning-Based Integration of Metabolomics Characterisation Predicts Progression of Myopic Retinopathy in Children and Adolescents.

Myopic retinopathy is an important cause of irreversible vision loss and blindness. As metabolomics has recently been successfully applied in myopia research, this study sought to characterize the serum metabolic profile of myopic retinopathy in children and adolescents (4-18 years) and to develop a diagnostic model that combines clinical and metabolic features. We selected clinical and serum metabolic data from children and adolescents at different time points as the training set (n = 516) and the validation set (n = 60). All participants underwent an ophthalmologic examination. Untargeted metabolomics analysis of serum was performed. Three machine learning (ML) models were trained by combining metabolic features and conventional clinical factors that were screened for significance in discrimination. The better-performing model was validated in an independent point-in-time cohort and risk nomograms were developed. Retinopathy was present in 34.2% of participants (n = 185) in the training set, including 109 (28.61%) with mild to moderate myopia. A total of 27 metabolites showed significant variation between groups. After combining Lasso and random forest (RF), 12 modelled metabolites (mainly those involved in energy metabolism) were screened. Both the logistic regression and extreme Gradient Boosting (XGBoost) algorithms showed good discriminatory ability. In the time-validation cohort, logistic regression (AUC 0.842, 95% CI 0.724-0.96) and XGBoost (AUC 0.897, 95% CI 0.807-0.986) also showed good prediction accuracy and had well-fitted calibration curves. Three clinical characteristic coefficients remained significant in the multivariate joint model (p < 0.05), as did 8/12 metabolic characteristic coefficients. Myopic retinopathy may have abnormal energy metabolism. Machine learning models based on metabolic profiles and clinical data demonstrate good predictive performance and facilitate the development of individual interventions for myopia in children and adolescents.

Osteopontin's colocalization with the adhesion molecule CEACAM5 in cytoplasm of carcinoma of tongue and its correlation with the invasion of that diease.

The purpose of this study was to investigate the expression of carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) and correlate it with OPN expression and function in squamous carcinoma of tongue.Paraffin were sections of 80 samples with squamous carcinoma of tongue and 40 samples with normal tissue of tongue for benign lesion having undergone surgery. Immunohistochemistry (IHC) was used to study the distribution of CEACAM5 and OPN, and double-labeling immunohistochemistry was used to observe the relationship between CEACAM5 and OPN expression.CEACAM5 and OPN are found in normal tissue of tongue, but with different expression pattern. CEACAM5 expression mainly with membranous staining is restricted on the superficial epithelium. However, OPN expression with mainly cytoplasmic staining is restricted on the deep epithelium. No colocalization of CEACAM5 and OPN have been observed in normal tissue of tongue. In squamous carcinoma of tongue, CEACAM5 expression with cytoplasmic staining is different from normal tongue tissue with membranous staining, and the transformation of CEACAM5 distribution from membrane to cytoplasm is an important incident for the invasion and differentiation of tumor. CEACAM5 and OPN are colocalized in cytoplasm, and a significant correlation was observed between the positive colocalization and the negative colocalization in the depth of invasion and the differentiation of the tumor.

Cooperative scheduling of imaging observation tasks for high-altitude airships based on propagation algorithm.

The cooperative scheduling problem on high-altitude airships for imaging observation tasks is discussed. A constraint programming model is established by analyzing the main constraints, which takes the maximum task benefit and the minimum cruising distance as two optimization objectives. The cooperative scheduling problem of high-altitude airships is converted into a main problem and a subproblem by adopting hierarchy architecture. The solution to the main problem can construct the preliminary matching between tasks and observation resource in order to reduce the search space of the original problem. Furthermore, the solution to the sub-problem can detect the key nodes that each airship needs to fly through in sequence, so as to get the cruising path. Firstly, the task set is divided by using k-core neighborhood growth cluster algorithm (K-NGCA). Then, a novel swarm intelligence algorithm named propagation algorithm (PA) is combined with the key node search algorithm (KNSA) to optimize the cruising path of each airship and determine the execution time interval of each task. Meanwhile, this paper also provides the realization approach of the above algorithm and especially makes a detailed introduction on the encoding rules, search models, and propagation mechanism of the PA. Finally, the application results and comparison analysis show the proposed models and algorithms are effective and feasible.

Spatial Distribution Characteristics and Influencing Factors of Traditional Villages on the Tibetan Plateau in China.

The Tibetan Plateau is one of the world's most extreme habitats and one of the most challenging ecosystems on the planet. Many multi-ethnic traditional villages have developed on the plateau over its long history, and are an essential component of human settlement. It is critical to research them, and it is also significant for China's goals to make the Tibetan Plateau a distinctive ethnic cultural preservation site and a world tourist destination. While there have been limited studies focusing on villages in the entire Tibetan Plateau area, as a result, we aim to expand the field of research on the regional study of traditional villages and make progress in research throughout the Tibetan Plateau. The question addressed in this study is what the current characteristics of the distribution of traditional villages on the Tibetan Plateau are, and we attempt to propose suggestions for the preservation of traditional villages according to the distribution characteristics. Methods such as the closest neighbor index, kernel density estimates, and spatial autocorrelation analysis are used to investigate the characteristics of the spatial distribution of traditional Chinese villages on the Tibetan Plateau, as well as regression analysis of the factors that control this distribution. The findings indicate that traditional villages are unevenly distributed over the plateau, with fewer villages in the northwest and more in the southeast, showing an agglomeration type of distribution. The village distribution on provincial and municipal is uneven with a large step difference. Tibetans make up the majority of the population in the villages, but other ethnic groups are present at the margins of the plateau. The distribution of traditional villages shows "big scattered, small gather" characteristics, and one core cluster (the Hehuang Valley area of Qinghai Province) and five high-density areas (the western Sichuan Plateau; the Three Parallel Rivers area of Yunnan Province; the Yarlung Zangbo, Nyangqu, and Lhasa rivers (YZN) area of Tibet Province; the Yushu area of Qinghai Province; and the Gannan area of Gansu and Sichuan province). The natural environment has the strongest influence on the distribution of traditional villages, followed by human impacts, especially concerning the distribution of single and multi-ethnic villages, and socioeconomic factors, which have multiple influences.

Application value of a deep learning method based on a 3D V-Net convolutional neural network in the recognition and segmentation of the auditory ossicles.

Objective: To explore the feasibility of a deep learning three-dimensional (3D) V-Net convolutional neural network to construct high-resolution computed tomography (HRCT)-based auditory ossicle structure recognition and segmentation models. Methods: The temporal bone HRCT images of 158 patients were collected retrospectively, and the malleus, incus, and stapes were manually segmented. The 3D V-Net and U-Net convolutional neural networks were selected as the deep learning methods for segmenting the auditory ossicles. The temporal bone images were randomized into a training set (126 cases), a test set (16 cases), and a validation set (16 cases). Taking the results of manual segmentation as a control, the segmentation results of each model were compared. Results: The Dice similarity coefficients (DSCs) of the malleus, incus, and stapes, which were automatically segmented with a 3D V-Net convolutional neural network and manually segmented from the HRCT images, were 0.920 ± 0.014, 0.925 ± 0.014, and 0.835 ± 0.035, respectively. The average surface distance (ASD) was 0.257 ± 0.054, 0.236 ± 0.047, and 0.258 ± 0.077, respectively. The Hausdorff distance (HD) 95 was 1.016 ± 0.080, 1.000 ± 0.000, and 1.027 ± 0.102, respectively. The DSCs of the malleus, incus, and stapes, which were automatically segmented using the 3D U-Net convolutional neural network and manually segmented from the HRCT images, were 0.876 ± 0.025, 0.889 ± 0.023, and 0.758 ± 0.044, respectively. The ASD was 0.439 ± 0.208, 0.361 ± 0.077, and 0.433 ± 0.108, respectively. The HD 95 was 1.361 ± 0.872, 1.174 ± 0.350, and 1.455 ± 0.618, respectively. As these results demonstrated, there was a statistically significant difference between the two groups (P < 0.001). Conclusion: The 3D V-Net convolutional neural network yielded automatic recognition and segmentation of the auditory ossicles and produced similar accuracy to manual segmentation results.