Multi-feature, Chinese-Western medicine-integrated prediction model for diabetic peripheral neuropathy based on machine learning and SHAP.

BACKGROUND: Clinical studies have shown that diabetic peripheral neuropathy (DPN) has been on the rise, with most patients presenting with severe and progressive symptoms. Currently, most of the available prediction models for DPN are derived from general clinical information and laboratory indicators. Several Traditional Chinese medicine (TCM) indicators have been utilised to construct prediction models. In this study, we established a novel machine learning-based multi-featured Chinese-Western medicine-integrated prediction model for DPN using clinical features of TCM. MATERIALS AND METHODS: The clinical data of 1581 patients with Type 2 diabetes mellitus (T2DM) treated at the Department of Endocrinology of the First Affiliated Hospital of Anhui University of Chinese Medicine were collected. The data (including general information, laboratory parameters and TCM features) of 1142 patients with T2DM were selected after data cleaning. After baseline description analysis of the variables, the data were divided into training and validation sets. Four prediction models were established and their performance was evaluated using validation sets. Meanwhile, the accuracy, precision, recall, F1 score and area under the curve (AUC) of ROC were calculated using ten-fold cross-validation to further assess the performance of the models. An explanatory analysis of the results of the DPN prediction model was carried out using the SHAP framework based on machine learning-based prediction models. RESULTS: Of the 1142 patients with T2DM, 681 had a comorbidity of DPN, while 461 did not. There was a significant difference between the two groups in terms of age, cause of disease, systolic pressure, HbA1c, ALT, RBC, Cr, BUN, red blood cells in the urine, glucose in the urine, and protein in the urine (p < 0.05). T2DM patients with a comorbidity of DPN exhibited diverse TCM symptoms, including limb numbness, limb pain, hypodynamia, thirst with desire for drinks, dry mouth and throat, blurred vision, gloomy complexion, and unsmooth pulse, with statistically significant differences (p < 0.05). Our results showed that the proposed multi-featured Chinese-Western medicine-integrated prediction model was superior to conventional models without characteristic TCM indicators. The model showed the best performance (accuracy = 0.8109, precision = 0.8029, recall = 0.9060, F1 score = 0.8511, and AUC = 0.9002). SHAP analysis revealed that the dominant risk factors that caused DPN were TCM symptoms (limb numbness, thirst with desire for drinks, blurred vision), age, cause of disease, and glycosylated haemoglobin. These risk factors were exerted positive effects on the DPN prediction models. CONCLUSIONS: A multi-feature, Chinese-Western medicine-integrated prediction model for DPN was established and validated. The model improves early-stage identification of high-risk groups for DPN in the diagnosis and treatment of T2DM, while also providing informative support for the intelligent management of chronic conditions such as diabetes.

Five-week music therapy improves overall symptoms in schizophrenia by modulating theta and gamma oscillations.

Introduction: Some clinical studies have shown that music therapy as an adjunctive therapy can improve overall symptoms in patients with schizophrenia. However, the neural mechanisms of this improvement remain unclear due to insufficient neuroimaging evidence. Methods: In this work, 17 patients with schizophrenia accepted a five-week music therapy (music group) that integrated listening, singing, and composing, and required patients to cooperate in a group to complete music therapy tasks. Meanwhile, 15 patients with schizophrenia received a five-week visual art intervention as the control group including handicraft and painting activities. We collected the Manchester Scale (MS) and Positive and Negative Symptom Scale (PANSS) scores and electroencephalography (EEG) data before and after intervention in two groups. Results: Behavioral results showed that both interventions mentioned above can effectively help patients with schizophrenia relieve their overall symptoms, while a trend-level effect was observed in favor of music therapy. The EEG results indicated that music therapy can improve abnormal neural oscillations in schizophrenia which is reflected by a decrease in theta oscillation in the parietal lobe and an increase in gamma oscillation in the prefrontal lobe. In addition, correlation analysis showed that in the music group, both reductions in theta oscillations in the parietal lobe and increases in gamma oscillations in the prefrontal lobe were positively correlated with the improvement of overall symptoms. Discussion: These findings help us to better understand the neural mechanisms by which music therapy improves overall symptoms in schizophrenia and provide more evidence for the application of music therapy in other psychiatric disorders.

Chain mediation model of consultation empathy, resilience and resignation coping on depression: a cross-sectional study among patients with COVID-19 in China.

OBJECTIVES: This study aimed to explore the mediating role of resilience and resignation coping in the relationship between consultation empathy and depression in patients with COVID-19. DESIGN: Cross-sectional study. SETTING: Participants were recruited from a tertiary hospital in Guangzhou, Guangdong province. PARTICIPANTS: A total of 215 patients were recruited for this study. OUTCOME MEASURES: A total of 215 patients completed the Consultation and Relational Empathy Measure, Connor-Davidson Resilience Scale, Medical Coping Modes Questionnaire and Hospital Anxiety and Depression Scale. PROCESS 4.1 model 6 was used to analyse the moderated mediating effects. RESULTS: Consultation empathy had a positive correlation with resilience (r=0.34, p<0.001), and a negative correlation with resignation (r=-0.288, p<0.001) and depression (r=-0.379, p<0.001). Resilience had a negative correlation with resignation (r=-0.463, p<0.001) and depression (r=-0.605, p<0.001). Resignation had a positive correlation (r=0.547, p<0.001) with depression. In the moderated mediating model, consultation empathy had significant indirect predictive effects on depression through resilience (95% CI -0.093 to -0.030) or resignation (95% CI -0.043 to -0.005). Consultation empathy had significant indirect predictive effects on depression through both resilience and resignation (95% CI -0.030 to -0.008). CONCLUSIONS: Consultation empathy not only predicted depression directly, but also indirectly predicted depression through the chain mediating effects of resilience and resignation coping.

Effect of particles size of TiC on oxidation resistance of in-situ TiC/Ni composite.

The oxidation resistance of TiC/Ni composites is crucial for its application in high-temperature oxidation environment. The in-situ TiC/Ni composites are fabricated by reactive sintering method, and the influence of TiC particle size on oxidation resistance of composite is studied. The particle size of TiC increases from 1.54 µm to 2.40 µm as the sintering holding time prolongs from 2 h to 6 h, due to the dissolution-reprecipitation mechanism. The oxidation kinetics of in-situ TiC/Ni composite with different TiC particle size oxidized at 800 °C for 100 h obeys parabolic kinetics. The oxidation mass gain of composite increases from 7.471 mg•cm-2 to 8.454 mg•cm-2, and the oxide scale on composites becomes thicker, as the particle size of TiC increases from 1.54 µm to 2.40 µm. The reduction of TiC particle size facilitates the formation of a dense and continuous oxide scale on composite, helpful to restrict the diffusion of O, Ti and Ni atoms during oxidation. Therefore, the reduction of TiC particle size is contributed to the optimization of oxidation resistance of in-situ TiC/Ni composites.

Microstructure and Mechanical Properties of HfC-SiC Ceramics Influenced by WC Addition.

The development of HfC-SiC has been challenging due to difficulties in achieving sintering and satisfactory mechanical properties. However, this study aims to overcome these limitations by incorporating WC as an additive. SPS was employed to process HfC-SiC and HfC-SiC doped with 5 vol.% WC. The resulting samples were then evaluated for their oxygen content, relative density, Vickers hardness, bending strength, indentation fracture toughness, and microstructure. The Vickers hardness (20.50 ± 0.20 GPa), flexural strength (600.19 ± 84.00 MPa), and indentation fracture toughness (5.76 ± 0.54 MPa·m1/2) of HfC-30 vol.% SiC-5 vol.% WC ceramics are higher than HfC-30 vol.% SiC ceramics. Doping 5 vol.% WC in HfC-30 vol.% SiC not only reduces the oxygen content of samples but also produces the (Hf,W)C solid solution and refines the microstructures, which are the main reasons for the higher mechanical properties of HfC-30 vol.% SiC-5 vol.% WC ceramics. In summary, this study successfully addresses the challenges associated with HfC-SiC by incorporating WC as an additive, leading to improved mechanical properties and microstructures.

Symbiotic treatment of ammonia-nitrogen wastewater by algae and activated sludge: effects of algae and sludge inoculation rates.

A symbiotic microalgal-bacterial system may be an optional technology for wastewater treatment. It was composed of microalgae and activated sludge and established in the SBR to explore the effect of different dosing ratios of algae and sludge on the removal of nitrogen and phosphorus from simulated wastewater containing ammonium. It can be seen from the result that varied algae-sludge dosing ratios had a higher removal effect on COD removal, but the difference was not significant. The algal-bacterial symbiosis system had a 100% removal rate for ammonium removal on the 8th day. Relatively speaking, the removal of nutrients and related mechanisms vary with environmental conditions (inoculation rate). In general, when the additive ratio was 5:1 (algae: AS), the removal rate of TN and TP was the highest, reaching 53.85% and 85.13% in the shortest time (14 days), among them, the removal rate of ammonium and COD was 100%, and the reduction rates of Nitrite nitrogen and Nitrate nitrogen were 362.99% and 73.42%, respectively. In addition, 16S rDNA gene analysis results demonstrated that the microbial community in the reactor with algal sludge inoculation ratio of 5:1 had differences in three stages of the initial reaction, the middle reaction and the end of the reaction. Comamonadaceae, Flavobacterium, Paenarthrobacter, Mesorhizobium, Nitrobacter were enriched during the reaction operation.

Dual-network polyacrylamide/carboxymethyl chitosan-grafted-polyaniline conductive hydrogels for wearable strain sensors.

Conductive, wearable, and flexible hydrogel-based sensors are considered as promising applications in human motion detection and physiological signal monitoring. However, it is still a problem to integrate multiple functions into one material for the next-generation smart devices. Herein, we fabricated an ionic/electronic dual conductive hydrogel by combining the chemically crosslinked polyacrylamide (PAM) and the physically crosslinked carboxymethyl chitosan-grafted-polyaniline (CMCS-g-PANI)/Ag+ network. The double-network hydrogel displays a high stretchability, repeatable adhesiveness, antibacterial activities, and biocompatibility. It also has high sensitivity and stable electrical performance for wearable strain sensors. Furthermore, we assembled a self-powered strain sensor based on the conversion of chemical energy to electrical energy. It can be used for human motion detection even without external power supply. This work provides an avenue for the development of multifunctional hydrogels with outstanding mechanical and electronic performances for application in wearable electronic devices.

Research about the capacitance properties of ion-induced multilayer and self-assembled monolayer Ti3C2T x.

MXenes materials are two-dimensional inorganic materials with abundant surface sites as capacitors. Better control of its morphology and expression of surface groups helps to improve the performance of capacitors. Herein, we controlled the morphology of MXenes with HF, HCl-LiF etching conditions, alkali and metal ions inducing factors. Benefiting from the nanostructures, the capacitance of HCl-LiF-prepared self-assembled monolayer Ti3C2T x soared to 370.96 F g-1 from 32.09 F g-1 of HF-etched multilaminate Ti3C2T x . As a result of the introduction of ions, the surface termination group is replaced by -OH with -F. Profit from this, the alkalized single-deck plicated Ti3C2T x exhibited a supernal capacitance up to 684.53 F g-1 because of the wrinkled morphology and more -OH terminal groups. Meanwhile, metal ion abduction brought some negative effects to electrochemical properties due to the oxidation of high-valent metal ions potentially.

Expression Analysis Reveals That Sorghum Disease Resistance Protein SbSGT1 Is Regulated by Auxin.

SGT1 (suppressor of the skp1 G2 allele) is an important plant disease resistance-related protein, which plays an important role in plant resistance to pathogens and regulates signal transduction during the process of plant disease resistance. In this study, we analyzed the expression profile of SbSGT1 in sorghum under phytohormones treatment. Quantitative real-time PCR results showed that SbSGT1 was most expressed in sorghum leaves, and could respond to plant hormones such as auxin, abscisic acid, salicylic acid, and brassinolide. Subsequently, we determined the optimal soluble prokaryotic expression conditions for SbSGT1 and purified it using a protein purification system in order to evaluate its potential interactions with plant hormones. Microscale thermophoretic analysis showed that SbSGT1 exhibited significant interactions with indole-3-acetic acid (IAA), with a Kd value of 1.5934. Furthermore, the transient expression of SbSGT1 in Nicotiana benthamiana indicated that treatment with exogenous auxin could inhibit SbSGT1 expression, both at the transcriptional and translational level, demonstrating that there exists an interaction between SbSGT1 and auxin.

Characterization of histone deacetylases and their roles in response to abiotic and PAMPs stresses in Sorghum bicolor.

BACKGROUND: Histone deacetylases (HDACs) play an important role in the regulation of gene expression, which is indispensable in plant growth, development, and responses to environmental stresses. In Arabidopsis and rice, the molecular functions of HDACs have been well-described. However, systematic analysis of the HDAC gene family and gene expression in response to biotic and abiotic stresses has not been reported for sorghum. RESULTS: We conducted a systematic analysis of the sorghum HDAC gene family and identified 19 SbHDACs mainly distributed on eight chromosomes. Phylogenetic tree analysis of SbHDACs showed that the gene family was divided into three subfamilies: RPD3/HDA1, SIR2, and HD2. Tissue-specific expression results showed that SbHDACs displayed different expression patterns in different tissues, indicating that these genes may perform different functions in growth and development. The expression pattern of SbHDACs under different stresses (high and low temperature, drought, osmotic and salt) and pathogen-associated molecular model (PAMPs) elf18, chitin, and flg22) indicated that SbHDAC genes may participate in adversity responses and biological stress defenses. Overexpression of SbHDA1, SbHDA3, SbHDT2 and SbSRT2 in Escherichia coli promoted the growth of recombinant cells under abiotic stress. Interestingly, we also showed that the sorghum acetylation level was enhanced when plants were under cold, heat, drought, osmotic and salt stresses. The findings will help us to understand the HDAC gene family in sorghum, and illuminate the molecular mechanism of the responses to abiotic and biotic stresses. CONCLUSION: We have identified and classified 19 HDAC genes in sorghum. Our data provides insights into the evolution of the HDAC gene family and further support the hypothesis that these genes are important for the plant responses to abiotic and biotic stresses.

Wide-range optical fiber temperature sensor based on up-conversion luminescent nanocrystals.

In this study, an optical fiber temperature sensor based on up-conversion luminescence (UCL) is proposed. The core part is a new plan of the sensing unit, which is constructed with UCL materials of NaYF4: Yb3+, Er3+ nanocrystals by fiber fusion technology to achieve a wide range of temperature measurements. Experimental results show that the proposed optical fiber temperature sensor shows significant spectrum-temperature characteristics in 80-373 K temperature range. Its relative sensitivities at low temperature and normal temperature are 2.2×10-3/K with a determination coefficient of 0.957 and 9.1×10-3/K with a determination coefficient of 0.994, respectively. This type of sensor also has good mechanical strength and system stability and shows great potential for development, particularly in the aerospace field with large temperature differences.

Bacterial Communities Associated with the Pine Wilt Disease Insect Vector Monochamus alternatus (Coleoptera: Cerambycidae) during the Larvae and Pupae Stages.

Monochamus alternatus is an important insect pest in pine forests of southern China and the dispersing vector of the pine wood nematode, Bursaphelenchus xylophilus, which leads to pine wilt disease (PWD). Microbiome of M. alternatus may contribute to survival of larvae in the host pine trees. In order to investigate the intestinal bacterial structure of M. alternatus during the larvae and pupae stages in host trees, and infer the function of symbiotic bacteria, we used 16S rRNA gene Illumina sequencing to obtain and compare the bacterial community composition in the foregut, midgut, and hindgut of larvae, pupal intestines, larval galleries, and pupal chambers of M. alternatus. The diversity of the bacterial community in larval intestines and pupal intestines were similar, as well as was significantly greater in larval galleries and pupal chambers. Although there were differences in bacterial compositions in different samples, similar components were also found. Proteobacteria and Firmicutes were the two most dominant phyla in all samples, and genera Enterobacter, Raoultella, Serratia, Lactococcus, and Pseudomonas were dominant in both the intestinal samples and plant tissue samples. Enterobacter was the most abundant genus in larval intestines, and Serratia was dominant in pupal intestine. The functions of these dominant and specific bacteria were also predicted through metagenomic analyses. These bacteria may help M. alternatus degrade cellulose and pinene. The specific role of symbiotic bacteria in the infection cycle of PWD also warrants further study in the future.

The Impact on Antioxidant Enzyme Activity and Related Gene Expression Following Adult Zebrafish (Danio rerio) Exposure to Dimethyl Phthalate.

Dimethyl phthalate (DMP) is a widespread environmental contaminant that poses potential toxicity risks for animals and humans. However, the toxicological effects of DMP on fish have not been adequately examined. In this study, the acute toxicity, oxidative damage, antioxidant enzyme activities, and relative gene expression patterns were investigated in the liver of adult zebrafish (Danio rerio) exposed to DMP. We found that the lethal concentration (LC50) of DMP for zebrafish after 96 h of exposure was 45.8 mg/L. The zebrafish that were exposed to low, medium and high concentrations of DMP (0.5, 4.6, and 22.9 mg/L, respectively) for 96 h had an increased malondialdehyde (MDA) content and a lower antioxidant capacity compared with the control solvent group. The total superoxide dismutase (SOD) activity was significantly higher than 0 h after initial exposure for 24 h at low concentrations, and then decreased at high concentrations after exposure for 96 h. The catalase (CAT) and glutathione S-transferase (GST) activities were significantly reduced after 96 h of exposure to high concentrations of DMP, with the up- or down-regulation of the related transcriptional expression. These findings indicated that DMP could cause physiological effects in zebrafish by disturbing the expression levels of antioxidant enzymes. These results might contribute to the identification of biomarkers to monitor phthalate pollution.

Degradation of azo dyes under visible light with stable MOF based on tetrastyrene imidazole ligand.

In the present work, a new 3D metal-organic framework (MOF) has been synthesized and characterized. The MOF exhibits good chemical stability in aqueous solutions with the pH scale ranging from 3 to 11. Interestingly, the MOF shows high catalytic activities for the degradation of azo dyes (MO, CR and CBR) under visible light without H2O2. The Ea values of the MOF for MO, CR and CBR degradation are obtained to be 23.49, 52.68 and 15.19 kJ mol-1, respectively. In addition, the MOF can be reused in the catalytic process without the catalytic activity decreasing obviously.

Improved Photoreduction of CO2 with Water by Tuning the Valence Band of Covalent Organic Frameworks.

Porous covalent organic frameworks (COFs), as an emerging material, have the characteristics of high stability, large series of components, easy synthesis, modification, and adjustable amplitude. They have the potential to become good catalysts. Bromine, as a halogen, has attracted intensive interest for the modification of photocatalysts for photocatalytic reactions. It is feasible to enhance the activity and selectivity of the material by facile functionalization of the reticular parent structure's electron-withdrawing groups. In addition, the conjugation effect of bromine, further delocalizing the electrons of the COF, is beneficial to the progress of many photocatalytic reactions. Reports on the modification of COFs by bromine functional groups to improve the catalytic performance have not been found so far. Here, TAPP [5,10,15,20-tetrakis(4-aminophenyl)porphyrin] and 2,5-dibromo-1,4-benzenedialdehyde instead of terephthalaldehyde were chosen to synthesize a porphyrin-based COF (TAPBB-COF) by the solvothermal method. As expected, the valence band (VB) of TAPBB-COF is thus adjusted to a more suitable position. Additionally, the CO production when using TAPBB-COF under full-wavelength light for 12 h was 295.2 µmol g-1 , which was three times that of COF-366, and the new material has good recycling stability and selectivity (95.6 %). Theoretical calculations indicate that the nitrogen of the porphyrin ring and the Schiff base, and the bromine in TAPBB-COF contribute greatly to the activation of H2 O and the conversion of CO2 in the photoreaction.

The preparation of new covalent organic framework embedded with silver nanoparticles and its applications in degradation of organic pollutants from waste water.

A covalent organic framework (COF) featuring a unique light porous structure and silver nanoparticles shows high efficiency in the degradation of environmental pollutants. However, the combination of a COF with silver nanoparticles has never been reported until now. Toward this end, 2,4,6-tris-(4-formylphenoxy)-1,3,5-triazine (TPT-CHO) and hydrazine hydrate were selected as the construction units of the COF material (TPHH-COF), which possesses rich nitrogen and oxygen sites. Then a new type of composite catalyst (Ag@TPHH-COF) was successfully obtained by solution infiltration. The obtained materials were also fully characterized by standard methods. The results showed that the silver nanoparticles (with diameters of 5 ± 3 nm) were uniformly dispersed on the surface and in the interlayer gaps of the TPHH-COF substrate. Catalytic studies showed that Ag@TPHH-COF could catalyze the reduction of the various nitroaromatic compounds (NACs) with high efficiency, such as 4-nitrophenol, 2-nitrophenol, 4-nitroaniline, nitrobenzene, 4-nitrotoluene and 1-butyl-4-nitrobenzene. Ag@TPHH-COF could also catalyze the reduction of organic dyes such as Rhodamine B (RhB), Methylene Blue (MB), Methyl Orange (MO) and Congo Red (CR). Moreover, Ag@TPHH-COF has good reusability and high recovery.

Analgesic Effects of Oxycodone Relative to Those of Sufentanil, in the Presence of Midazolam, During Endoscopic Injection Sclerotherapy for Patients With Cirrhosis and Esophageal Varices.

BACKGROUND: We evaluated the efficacy and gastroenterologist/patient satisfaction of midazolam combined with oxycodone, relative to that of midazolam combined with sufentanil, for anesthesia during endoscopic injection sclerotherapy (EIS) in patients with cirrhosis and esophageal varices. METHODS: Patients with cirrhosis (20-69 years of age), body mass index, 18-25 kg/m, American Society of Anesthesiology patient classification physical status I-II who underwent elective EIS were randomly assigned to 1 of 2 groups. In this prospective, double-blinded, randomized controlled trial, 1 group received midazolam and oxycodone (n = 64), and the other group received midazolam and sufentanil (n = 63). Primary and secondary outcome measures were compared between groups. The primary outcome measure was the incidence of hypoxia. Secondary outcome measures included perioperative limb movement, need for rescue analgesics, need for additional sedative propofol, specified adverse reactions (postoperative myoclonus, nausea, vomiting, dizziness, and drowsiness), gastroenterologist satisfaction, and patient satisfaction with postoperative analgesia. RESULTS: Patients in the midazolam-oxycodone group had 32% fewer episodes of hypoxia than did those in the midazolam-sufentanil group (95% confidence interval [CI], -45% to -18%; P < .001), 36.73% fewer perioperative limb movements (95% CI, -51.73% to -21.73%; P < .001), 19.12% fewer required rescue analgesics (95% CI, -30.85% to -7.40%; P = .002), and less propofol requirement in the perioperative period (before EIS, -17.83%; 95% CI, -33.82% to -1.85%; P = .003; throughout EIS, -36.73%; 95% CI, -51.73% to -21.73%; P < .001). The incidence rates for adverse reactions were similar between groups. Both the gastroenterologist and patients reported higher degrees of satisfaction with oxycodone than with sufentanil. CONCLUSIONS: Oxycodone in combination with midazolam may provide an anesthetic technique that results in fewer episodes of hypoxia and other adverse conditions during EIS.

Effect of a LECT2 on the immune response of peritoneal lecukocytes against Vibrio anguillarum in roughskin sculpin.

Leukocyte cell-derived chemotaxin 2 (LECT2) is a multi-functional protein that is mainly synthesized by the liver. However, its role in roughskin scalping is less known. Here, we cloned a leukocyte cell-derived chemotaxin 2 (TfLECT2) genes in the liver of roughskin scalping, Trachidermus fasciatus, and studied its possible role involved in the immune response against Vibrio anguillarum (V. anguillarum) of peritoneal lecukocytes under in vivo conditions. The cDNA sequence of TfLECT2 is 566 bp in size. Its deduced amino acid (aa) sequence comprises 151 residues, of which the first 16 residues form a putative signal peptide and 101 residues compose a typical peptidase M23 domain in the C-terminal region. The domain structure is conserved in all LECT2 proteins, which suggests a close phylogenetic relationship between TfLECT2 and LECT2 in other fish species. Real-time quantitative PCR analysis revealed that TfLECT2 gene expression was dramatically increased in liver after V. anguillarum stimulation. Subsequently, TfLECT2 was prokaryotic expressed and purified to prepare anti-TfLECT2 antibody. After V. anguillarum challenge, leukocytes recruitment and LECT2 levels in peritoneal exudates were increased, and positively correlated with each other. Moreover, recombinant TfLECT2 administration significantly improved immune responses after infection, principally in stimulating the recruitment, phagocytosis and respiratory burst of leukocytes at the site of infection; however, anti-TfLECT2 treatment neutralized these abilities. Therefore, TfLECT2 may trigger the early immune events of peritoneal leukocytes and it will be useful to induce innate immune response of fish.

Study on characteristics of single cavitation bubble considering condensation and evaporation of kerosene steam under ultrasonic vibration honing.

Ultrasonic vibration honing technology is an effective means for materials difficult to machine, where cavitation occurs in grinding fluid under the action of ultrasound. To investigate the changes of single cavitation bubble characteristics in the grinding area and how honing parameters influence bubble characteristics, a dynamic model of single cavitation bubble in the ultrasonic vibration honing grinding area was established. The model was based on the bubble dynamics and considered the condensation and evaporation of kerosene steam and honing processing environment. The change rules of bubble radius, temperature, pressure and number of kerosene steam molecules inside the bubble were numerically simulated in the process of bubble moving. The results show that the condensation and evaporation of kerosene steam can help to explain the changes of temperature and pressure inside the bubble. Compared with ultrasonic vibration, the amplitude of bubble radius is greatly suppressed in the ultrasonic honing environment. However, the rate of movement of the bubble is faster. Meanwhile, the minimum values of pressure and temperature are larger, and the number of kerosene steam molecules is less. By studying the effect of honing factors on the movement of the cavitation bubble, it is found that honing pressure has a greater influence on bubble evolution characteristics, while rotation speed of honing head has a minor effect and the reciprocating speed of honing head has little impacts.

[The relationships between oxygenation index and prognosis in acute respiratory failure patients treated by invasive mechanical ventilation].

OBJECTIVE: To investigate the effect of oxygenation index (PaO(2)/FiO(2)) on patients' prognosis through comparative analyzing the monitoring indicators of acute respiratory failure patients treated by invasive mechanical ventilation. METHODS: Data from 91 acute respiratory failure patients treated by invasive mechanical ventilation in respiration intensive care unit (ICU) of the General Hospital of PLA of Lanzhou from November 2006 to August 2011 were retrospectively analyzed. Patients were divided into survival group (n=55) and death group (n=36) by the outcome, the critical severity scores of the diseases and changes in blood gas analysis during ventilation were compared, and their correlation with prognosis were analyzed. RESULTS: There were no significant differences in acute physiology and chronic health evaluationIII (APACHEIII) score, multiple organ dysfunction syndrome (MODS) score, acute lung injury (ALI) score between survival and death group before ventilation (62.77±22.92 vs. 74.62±25.77, 6.46±2.45 vs. 6.62±3.03, 1.90±0.57 vs. 2.10±0.73, all P>0.05). There was no significant difference in PaO(2)/FiO(2) between survival and death group on the first day of mechanical ventilation (132.18±67.29 mm Hg vs. 139.24±78.36 mm Hg, P>0.05). PaO(2)/FiO(2) in survival group were significantly higher than that in death group on the 3 days and 7 days of mechanical ventilation (3 days: 205.47±74.71 mm Hg vs. 149.76±70.38 mm Hg, 7 days: 225.37±67.20 mm Hg vs. 120.94±85.58 mm Hg, P<0.05 and P<0.01). CONCLUSIONS: The present study demonstrated that the level of PaO(2)/FiO(2) is related with the prognosis of acute respiratory failure patients treated by invasive mechanical ventilation. Continuously monitoring the changes in PaO(2)/FiO(2) can be used as an important reference index to evaluate the prognosis of critical patients.