Objective This study compared organ doses and effective doses in typical adult patients during dental CBCT examinations using a head-and-neck anthropomorphic phantom and a whole-body phantom. It aimed to determine an appropriate method for evaluating effective dose in dental CBCT. Methods A domestically manufactured dental CBCT unit was used to scan an adult male anthropomorphic phantom under simulated clinical conditions. Thermoluminescent dosimeters were placed on organs and tissues of a whole-body anthropomorphic phantom. Organ equivalent doses were measured, and effective doses were calculated using two approaches: one based on all organ doses from the whole-body phantom, and the other based only on head-and-neck organ doses. Entrance surface air kerma (K_a,e) was also measured at the lens of the eye, thyroid, thymus, and gonads. Results The effective dose estimated with the whole-body phantom was 382.03 μSv. The effective dose estimated with the head-and-neck phantom was 354.03 μSv. The radiation dose to head-and-neck organs and tissues accounted for 92.7% of the total effective dose. The highest K_a,e values were found in the parotid glands, followed by the lens of the eye. Conclusion During dental CBCT scanning, the contribution of organ below the head and neck to the total effective dose is limited. To simplify dose assessment procedures, the effective dose for the patient can be evaluated using only a head-and-neck phantom.

In the field of substance detection,ion dissociation techniques have become crucial for enhancing qualitative accuracy.By applying external energy to induce dissociation of ions in the substance being analyzed,the internal structural information can be obtained,thereby improving qualitative capabilities.Current research on ion dissociation techniques primarily focuses on tandem mass spectrometry,which typically requires a vacuum environment.However,research on ambient ion dissociation techniques is less developed,with some progress made in the field of tandem ion mobility spectrometry.Recently,the development of field-induced dissociation(FID)in this area has enabled ambient dissociation of various explosive and volatile alcohol ions.Nevertheless,the limitation imposed by the maximum breakdown field of air restricts the energy of the electric field,making it challenging to dissociate ions with high energy requirements,such as those of drugs.To address this issue,in this work,an ambient heat-induced dissociation(HID)technique based on high temperatures was proposed,in which an ambient ion heat-induced dissociation unit was developed and integrated into a home-made ion trap mass spectrometer.Experiments were conducted on four representative drug samples,e.g.methamphetamine,heroin,cocaine,and ketamine.The parent ions mass spectra,low vacuum collision-induced dissociation(CID)mass spectra and ambient HID mass spectra for each sample were obtained.By analyzing and comparing the fragmentation products from ambient and low vacuum dissociation,the feasibility of the ambient HID technique was verified.This technique provided a method for ion dissociation in single mass analyzers without tandem mass spectrometry capability and offered a new research direction for the future development of tandem ion mobility spectrometry.

Aerosol-assisted plasma amplification laser-induced breakdown spectroscopy(LIBS)was employed for phosphorus detection in water.To address the multivariate coupling effects in LIBS and nebulization sampling system,an orthogonal experiment was employed to systematically optimize the key experimental parameters.Using the orthogonal experimental design,the parametric effects of laser energy(output voltage),signal acquisition delay,liquid velocity,and gas velocity on the signal to background ratio(SBR)of P I 213.618 nm were evaluated,and the optimal conditions were achieved,including laser energy of 86 mJ,delay time of 3 μs,gas velocity of 1.05 mL/min,and liquid velocity of 60 μL/min,which were in agreement with the control-variable optimization results.Moreover,the SBR response trends at P I 213.618 nm with all experimental parameters was strong in consistency with control-variable optimization results,which demonstrated the validity of the orthogonal array experimental design.This study established an efficient and accurate parameter optimization methodology for complex LIBS systems,significantly advancing the application of LIBS in environmental monitoring.

Objective:To investigate the prevalence of flight fatigue among helicopter flying personnel and analyze its contributors in order to provide data for related interventions.Methods:A cross-sectional study was conducted among 404 helicopter flying personnel between October 8, 2021 and July 31, 2022. Data was collected using a self-designed questionnaire, involving the demography of these subjects, sleep-related factors, flight fatigue, perceived causes of fatigue and coping strategies. The Pittsburgh Sleep Quality Index (PSQI), National Aeronautics and Space Administration Task Load Index (NASA-TLX) and Modified Fatigue Impact Scale (MFI-20) were used to assess sleep quality, mental workload, and levels of flight fatigue over the past month. The total scores of MFI-20 were compared across demographic groups, and correlations with PSQI and NASA-TLX scores were analyzed. Multiple linear regression was performed to identify the determinants of flight fatigue.Results:①Demography: among the 404 helicopter flying personnel, 92.8% (375/404) were pilots and 7.2% (29/404) navigators. As for years of service, 41.6% (168/404) served less than 5 years, while 58.4% (236/404) served more than 5 years. 37.9% (153/404) had a family history of insomnia. 18.8% (76/404) did not habitually nap, 68.9% (226/328) napped for ≤30 min, 31.1% (102/328) napped over 30 min, and 18.3% (74/404) had insomnia over the past month. As for helicopter flying personnel, 75.5% (305/404) reported experiencing fatigue, with 69.1% (279/404) attributing it to flight-related factors and 51.5% (208/404) using coffee as a countermeasure.②Scale scores: the total score of PSQI was [5 (3, 7)], while the highest daytime dysfunction score was [1(0, 2)]. The total score of NASA-TLX was [39.19 (26.57, 51.97)], and the effort score was the highest [10.31(5.07, 14.60)]. The total score of MFI-20 averaged (47.28±14.88), with the mental fatigue score being the highest [(10.03±4.42)]. ③Comparisons of MFI-20 total scores: flying personnel with ≤5 years of flying experience had higher MFI-20 total scores than those with >5 years, and those with a family history of insomnia had higher scores than those without ( t=3.35, 2.44, P=0.001, 0.015). Individuals with insomnia over the past month had higher scores than non-insomniacs ( t=3.33, P=0.001). Significant differences in MFI-20 scores were observed based on nap duration ( F=19.95, P<0.001). Non-nappers had higher scores than those napping for ≤30 min ( P=0.005). Flying personnel who napped for >30 min had higher scores than those did not ( P=0.043) or napped for ≤30 min ( P<0.001). ④Correlation analysis: the total score of MFI-20 was positively correlated with sleep quality, sleep latency, sleep disturbances, hypnotic medications, daytime dysfunction, and the total score of PSQI ( r=0.118-0.226, all P<0.05), but negatively with sleep duration ( r=-0.136, P=0.006). The total score of MFI-20 was positively correlated with mental demand, physical demand, and the total score of NASA-TLX ( r=0.119, 0.168, 0.184, P=0.017, 0.001, <0.001). ⑤Multiple linear regression analysis: the determinants of flight fatigue included aircraft types ( B=-4.956, 95% CI:-8.124--1.788), nap duration ( B=3.693, 95% CI: 1.267-6.119), sleep latency ( B=2.371, 95% CI: 0.229-4.513), sleep duration ( B=-7.383, 95% CI:-10.008--4.758), daytime dysfunction ( B=5.003, 95% CI: 2.967-7.039) and physical workload ( B=0.611, 95% CI: 0.324-0.898). Conclusions:Helicopter flying personnel are vulnerable to flight fatigue, which is strongly linked to sleep quality and mental workload. It is crucial to address flying personnel′s self-perceived fatigue, care about fatigue manifestations across aircraft types, and implement targeted interventions to improve sleep quality and reduce mental workload.

Objective: The purpose of this study was to explore the capacity for energy production under conditions of increased energy demand in schizophrenia (SCZ) subjects compared to healthy controls. Methods: Twelve healthy controls (33.00±6.07 years) and 12 subjects diagnosed with SCZ or schizoaffective disorder (36.00±8.33 years) matched for age and sex, were recruited for this study. Hypoxic stress was induced during MR scans to elevate the energy demand on the subjects’ bioenergetic systems. Participants breathed air with a lower oxygen concentration (FiO2=13%), maintaining their SpO2 levels (86%) during the initial phase of the scan. 31Phosphorus MR spectroscopy was employed to examine metabolite levels, including phosphocreatine (PCr), β-adenosine triphosphate (ATP), and inorganic phosphate (Pi), as well as the ratios of PCr/Pi and PCr/β-ATP, in regions such as the prefrontal cortex (PFC), anterior cingulate cortex (ACC), and posterior cortex (POC), as well as across the entire brain, during both hypoxia and hyperoxia scans. Results: Subjects with SCZ had significantly lower levels of Pi across the brain and particularly, in the PFC, POC, and ACC during the hypoxia scan. Moreover, levels of PCr/Pi, indicative of mitochondrial energy production, were found to be higher in the same brain regions in the SCZ group. No significant differences were found in hyperoxia scan phase. Conclusion These findings suggest a deficit in the bioenergetic systems of individuals with SCZ under conditions of heightened energy demand. Further studies are warranted.

Objective To develop and validate a fast Monte Carlo(MC)-based patient-specific quality assurance(PSQA)tool using the treatment log files that is suitable to be used in the online adaptive radiotherapy for pencil beam scanning proton therapy(PBSPT-ART).Methods The proposed tool first used the delivery log file of a PBSPT plan to reversely reconstruct the PBSPT(rPBSPT)plan,and then used an in-house developed graphic processing unit(GPU)-accelerated virtual particle MC(VPMC)dose engine to calculate the dose distribution of the rPBSPT plan.The rPBSPT dose calculated by VPMC was then compared to the rPBSPT dose calculated by another independent MC dose engine(MCsquare),using 3D gamma analysis to verify the accuracy of VPMC calculation.As a demonstration of the feasibility of developed log file-based PSQA,the VPMC calculated dose of the rPBSPT plan was compared to the pre-delivery second check dose of the corresponding PBSPT plan calculated by MCsquare,using 3D gamma analysis.3D gamma analysis employes a criterion of 2 mm/2%/10%.Twenty patients with different disease sites were representatively selected to validate the efficiency and accuracy of the tool.Results The average calculation time of a rPBSPT plan by VPMC was(5.88±4.00)s in the accuracy verification.Compared to MCsquare,the passing rate of the 3D gamma analysis was 99.47%±0.72%.In the proposed PSQA tool demonstration,the passing rate of comparing the VPMC calculated rPBSPT dose to MCsquare calculated second check dose of the corresponding PBSPT plan was 98.91%±0.92%.Conclusion The accuracy and efficiency of the tool can meet the requirements of PSQA in the online PBSPT-ART workflow.

Objective To evaluate the efficacy and safety of transcatheter aortic valve implantation(TAVI)for the treatment of primary aortic valve regurgitation(NAVR)and to compare the difference in the choice of prosthetic valve size and the difference in complications with aortic stenosis(AS).Methods According to the definition of Valve Academic Research Consortium(VARC-3),143 patients with NAVR/AS treated with TAVI and patients with NAVR treated with surgical aortic valve replacement(SAVR)at Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology,China,from March 2019 to September 2024 were selected,and clinical data on baseline,perioperative,and primary endpoint events were were retrospectively collected and compared.Results Forty-three patients with NAVR were treated with TAVI,with a device success rate of 86.0％and a surgical success rate of 95.3％.Subgroup comparisons:(1)NAVR-TAVI group than NAVR-SAVR group:patients in the TAVI group had a significantly shorter operative time than those in the SAVR group(P＜0.001);complete left bundle branch block was more likely to occur after TAVI(P=0.042),and complete right bundle branch block was more likely to occur after SAVR(P=0.044).SAVR postoperatively The incidence of congestive heart failure was higher(P=0.013),and the mortality rate was significantly higher in the SAVR group than in the TAVI group(P=0.019).(2)NAVR-TAVI group than AS-TAVI group:the differences in access selection,THV size[28(22,34)mm vs.24(22,32)mm,P=0.044]and proportion of THV overdiameter[14％(7％,20％)vs.7％(3％,11％),P＜0.001]were statistically significant.patients in AS and NAVR groups had 1 case of permanent pacing after TAVI treatment.In the AS and NAVR groups,there was 1 case of permanent pacemaker implantation after TAVI.2 patients in the AS group were converted to surgical treatment,and 6 patients died.Conclusions The use of"off-label"(transfemoral)and"on-label"(transapical)TAVI devices(both from domestic sources)is safer than SAVR for the treatment of NAVR,especially in elderly and high-risk patients.Compared with patients with AS treated with TAVI,larger diameter annulas are usually selected for NAVR,with higher rates of valve migration,but overall safety and efficacy are comparable to AS.

Objective:To investigate the prevalence of flight fatigue among helicopter flying personnel and analyze its contributors in order to provide data for related interventions.Methods:A cross-sectional study was conducted among 404 helicopter flying personnel between October 8, 2021 and July 31, 2022. Data was collected using a self-designed questionnaire, involving the demography of these subjects, sleep-related factors, flight fatigue, perceived causes of fatigue and coping strategies. The Pittsburgh Sleep Quality Index (PSQI), National Aeronautics and Space Administration Task Load Index (NASA-TLX) and Modified Fatigue Impact Scale (MFI-20) were used to assess sleep quality, mental workload, and levels of flight fatigue over the past month. The total scores of MFI-20 were compared across demographic groups, and correlations with PSQI and NASA-TLX scores were analyzed. Multiple linear regression was performed to identify the determinants of flight fatigue.Results:①Demography: among the 404 helicopter flying personnel, 92.8% (375/404) were pilots and 7.2% (29/404) navigators. As for years of service, 41.6% (168/404) served less than 5 years, while 58.4% (236/404) served more than 5 years. 37.9% (153/404) had a family history of insomnia. 18.8% (76/404) did not habitually nap, 68.9% (226/328) napped for ≤30 min, 31.1% (102/328) napped over 30 min, and 18.3% (74/404) had insomnia over the past month. As for helicopter flying personnel, 75.5% (305/404) reported experiencing fatigue, with 69.1% (279/404) attributing it to flight-related factors and 51.5% (208/404) using coffee as a countermeasure.②Scale scores: the total score of PSQI was [5 (3, 7)], while the highest daytime dysfunction score was [1(0, 2)]. The total score of NASA-TLX was [39.19 (26.57, 51.97)], and the effort score was the highest [10.31(5.07, 14.60)]. The total score of MFI-20 averaged (47.28±14.88), with the mental fatigue score being the highest [(10.03±4.42)]. ③Comparisons of MFI-20 total scores: flying personnel with ≤5 years of flying experience had higher MFI-20 total scores than those with >5 years, and those with a family history of insomnia had higher scores than those without ( t=3.35, 2.44, P=0.001, 0.015). Individuals with insomnia over the past month had higher scores than non-insomniacs ( t=3.33, P=0.001). Significant differences in MFI-20 scores were observed based on nap duration ( F=19.95, P<0.001). Non-nappers had higher scores than those napping for ≤30 min ( P=0.005). Flying personnel who napped for >30 min had higher scores than those did not ( P=0.043) or napped for ≤30 min ( P<0.001). ④Correlation analysis: the total score of MFI-20 was positively correlated with sleep quality, sleep latency, sleep disturbances, hypnotic medications, daytime dysfunction, and the total score of PSQI ( r=0.118-0.226, all P<0.05), but negatively with sleep duration ( r=-0.136, P=0.006). The total score of MFI-20 was positively correlated with mental demand, physical demand, and the total score of NASA-TLX ( r=0.119, 0.168, 0.184, P=0.017, 0.001, <0.001). ⑤Multiple linear regression analysis: the determinants of flight fatigue included aircraft types ( B=-4.956, 95% CI:-8.124--1.788), nap duration ( B=3.693, 95% CI: 1.267-6.119), sleep latency ( B=2.371, 95% CI: 0.229-4.513), sleep duration ( B=-7.383, 95% CI:-10.008--4.758), daytime dysfunction ( B=5.003, 95% CI: 2.967-7.039) and physical workload ( B=0.611, 95% CI: 0.324-0.898). Conclusions:Helicopter flying personnel are vulnerable to flight fatigue, which is strongly linked to sleep quality and mental workload. It is crucial to address flying personnel′s self-perceived fatigue, care about fatigue manifestations across aircraft types, and implement targeted interventions to improve sleep quality and reduce mental workload.

Objective:To analyze the correlation and predictive value of obesity measurement indicators and cerebrovascular function scores in healthy physical examination population.Methods:It was a cross-sectional analysis that employed a simple random sampling method to select 3 496 individuals who underwent healthy physical examinations and cerebrovascular function tests at the Physical Examination Center of the Affiliated Hospital of Guizhou Medical University from January to December 2022. The general information, physical examination data, biochemical examination results, human component analyses, and cerebrovascular function integral data were collected. Based on cerebrovascular function scores, the participants were divided into high-risk group (0-24 points, 70 cases), medium-risk group (25-49 points, 317 cases), low-risk group (50-74 points, 787 cases), and normal group (≥75 points, 2 322 cases). Spearman correlation analysis and receiver operating characteristic (ROC) curve analyses were utilized to assess the correlation and predictive value of obesity measurement indicators and cerebrovascular function integrals.Results:Among the 3 496 subjects included in the analysis, 2 018 were male and 1 478 were female, with an average age of (46.4±7.9) years. The age, systolic blood pressure, diastolic blood pressure, body mass index, waist-to-hip ratio, body fat ratio, body fat content, visceral fat area, fasting blood glucose, total cholesterol, low-density lipoprotein, homocysteine all exhibited an increasing trend as the cerebrovascular function integral value decreased (all P<0.05). The skeletal muscle content in the low-risk group was significantly higher than those in the high-risk group, medium-risk group, and normal group [45.00 (36.80, 50.60) vs 44.10 (36.98, 50.45), 44.50 (37.80, 50.20), and 42.75 (36.30, 48.60) kg, respectively] ( P<0.05). The triglyceride level in the medium-risk group was higher when compared to those in the high-risk group, low-risk group, and normal group[1.87 (1.29, 2.70) vs 1.71 (1.24, 2.80), 1.75 (1.18, 2.70), and 1.43 (1.00, 2.14) mmol/L] ( P<0.05). The high-density lipoprotein level in the normal group was higher than the high-risk group, medium-risk group, and low-risk group[1.26 (1.05, 1.51) vs 1.16 (0.94, 1.36), 1.15 (0.99, 1.39), and 1.16 (0.97, 1.39) mmol/L, respectively] ( P<0.05). The increases in systolic blood pressure, diastolic blood pressure, body mass index, and body fat content were all moderately negatively correlated with the cerebrovascular function score ( rs=-0.347, -0.335, -0.370, and -0.340, respectively, all P<0.05). The increase in age ( OR=1.012, 95% CI: 1.002-1.022), systolic blood pressure ( OR=1.027, 95% CI: 1.017-1.036), diastolic blood pressure ( OR=1.028, 95% CI: 1.014-1.042), body mass index ( OR=1.157, 95% CI: 1.083-1.237), body fat rate ( OR=1.021, 95% CI: 1.007-1.035), and fasting blood glucose ( OR=1.072, 95% CI: 1.020-1.127) were all positively correlated with the decrease of the cerebrovascular function score; conversely, the increase in skeletal muscle content ( OR=0.967, 95% CI: 0.951-0.982) was negatively correlated with the decrease in cerebrovascular function score (all P<0.05). The area under the curve for the combined prediction of cerebrovascular function integral value by age, systolic blood pressure, diastolic blood pressure, body mass index, body fat rate, skeletal muscle content, and fasting blood glucose was 0.754. Conclusions:As the body mass index and body fat content increase and the skeletal muscle content decreases in the healthy physical examination population, the likelihood of abnormal cerebrovascular function integral values rises; the combination of age, systolic blood pressure, diastolic blood pressure, body mass index, body fat percentage, skeletal muscle content, and fasting blood glucose indicators can predict the increased risk of cerebrovascular function integral values.