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The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.
Background: Lower socioeconomic status is associated with worse outcomes after stroke. We evaluated the differences in acute revascularization treatments in patients with acute ischemic stroke (AIS) who were materially deprived compared to those who were not. Methods: In a population-based cohort study, we used linked administrative data to identify community-dwelling adults hospitalized for AIS between 2017-2022 in Ontario, Canada. The main exposure was neighborhood-level material deprivation quintiles. Multivariable logistic regression was used to obtain the adjusted odds ratio (aOR) of receiving revascularization treatments (thrombolysis or thrombectomy) for patients in each deprivation quintile compared to the least deprived quintile. Results: We identified 57,709 patients (median age 74 years; 45.9% female). Compared to patients in the least deprived quintile, those with higher deprivation were younger and more likely to have hypertension and diabetes, but less likely to have atrial fibrillation. Compared to patients in the least deprived quintile, fewer patients in the very deprived quintile (17.9% vs 19.6%, aOR 0.88, 95%CI [0.82,0.95]) and in the most deprived quintile (16.6% vs 19.6%, 0.77 [0.71,0.83]) received revascularization treatments. Conclusions: Our results suggest disparities in the use of acute ischemic stroke revascularization treatments by socioeconomic status despite access to universal health care.
To enhance the performance of anti-ship missiles cooperative attack, this paper proposes a finite-time trajectory shaping-based cooperative guidance law (TSCGL). Firstly, the cooperative guidance model is established on segmented linearisation of the missile’s heading angle. Then, a trajectory shaping guidance law for a single missile is derived by a weighted optimal energy cost function and Schwarz inequality. On this basis, a finite-time TSCGL is proposed combined with trajectory shaping technology and finite-time theory. The desirable finite-time convergence performance can ensure a simultaneous attack. Through an improved method of time-to-go estimation, it is independent of small-angle assumption and relaxes the launching conditions of the missiles. Additionally, the proposed finite-time TSCGL can achieve better damage performance through energy management. Finally, simulation results demonstrate the effectiveness and superiority of the proposed finite-time TSCGL.
This study aimed to establish a model for predicting the three-year survival status of patients with hypopharyngeal squamous cell carcinoma using artificial intelligence algorithms.
Data from 295 patients with hypopharyngeal squamous cell carcinoma were analysed retrospectively. Training sets comprised 70 per cent of the data and test sets the remaining 30 per cent. A total of 22 clinical parameters were included as training features. In total, 12 different types of machine learning algorithms were used for model construction. Accuracy, sensitivity, specificity, area under the receiver operating characteristic curve and Cohen's kappa co-efficient were used to evaluate model performance.
The XGBoost algorithm achieved the best model performance. Accuracy, sensitivity, specificity, area under the receiver operating characteristic curve and kappa value of the model were 80.9 per cent, 92.6 per cent, 62.9 per cent, 77.7 per cent and 58.1 per cent, respectively.
This study successfully identified a machine learning model for predicting three-year survival status for patients with hypopharyngeal squamous cell carcinoma that can offer a new prognostic evaluation method for the clinical treatment of these patients.
To assess the accuracy of the Varian PerfectPitch six-degree-of-freedom (6DOF) robotic couch by using a Varian SRS QA phantom.
The stereotactic radiosurgery (SRS) phantom has five tungsten carbide BBs each with 7·5 mm in diameter arranged with the known geometry. Optical surface images and cone beam CT (CBCT) images of the phantom were taken at different pitch, roll and rotation angles. The pitch, roll, and rotation angles were varied from −3 to 3 degrees by inputs from the linac console. A total of 39 Vision RT images with different rotation angle combinations were collected, and the Vision RT software was used to determine the rotation angles and translational shifts from those images. Eight CBCT images at most allowed rotational angles were analysed by in-house software. The software took the coordinates of the voxel of the maximum CT number inside a 7·5-mm sphere surrounding one BB to be the measured position of this BB. Expected BB positions at different rotation angles were determined by multiplying measured BB positions at zero pitch and roll values by a rotation matrix. Applying the rotation matrix to 5 BB positions yielded 15 equations. A linear least square method was used for regression analysis to approximate the solutions of those equations.
Of the eight calculations from CBCT images, the maximum rotation angle differences (degree) were 0·10 for pitch, 0·15 for roll and 0·09 for yaw. The maximum translation differences were 0·3 mm in the left–right direction, 0·5 mm in the anterior–posterior direction and 0·4 mm in the superior–inferior direction.
The uncertainties of the 6-DOF couch were examined with the methods of optical surface imaging and CBCT imaging of the SRS QA phantom. The rotational errors were less than 0·2 degree, and the isocentre shifts were less than 0·8 mm.
In view of the cooperative guidance problem with time delay, this paper proposes a two-stage time-delay prescribed-time cooperative guidance law in the three-dimensional (3D) space. In the first stage, by introducing a time scaling function and time-delay consensus, the proposed cooperative guidance law can overcome the negative influence of time delay to guaranteed the desired convergence performance. Derived from the Lyapunov convergence analysis, the time-delay stability of the first stage can be ensured and the convergence time can be described as the relationship between delayed time and mission-assigned convergence time. Then, taking the prescribed-time-related convergence time as the switching point, the second stage begins with suitable initial conditions and all interceptors are governed by proportional navigation guidance. Finally, comparative simulations are performed to demonstrate the effectiveness and superiority of the proposed time-delay guidance law.
In this paper, to address the cooperative localisation of a heterogeneous UAV swarm in the GNSS-denied environment, an adaptive simulated annealing-particle swarm optimisation (SA-PSO) cooperative localisation algorithm is proposed. Firstly, the forming principle of the communication and measurement framework is investigated in light of a heterogeneous UAV swarm composition. Secondly, a reasonably cooperative localisation function is established based on the proposed forming principle, which can minimise the relative localisation error with limited available information. Then, an adaptive weight principle is incorporated into the particle swarm optimisation (PSO) for better performance. Furthermore, in order to overcome the drawbacks of PSO algorithm easily falling into the local extreme point, an adaptive SA-PSO algorithm is improved to promote the convergence speed of cooperative localisation. Finally, comparative simulations are performed among the adaptive SA-PSO, adaptive PSO, and PSO algorithms to demonstrate the feasibility and superiority of the proposed adaptive SA-PSO algorithm. Simulation results show that the proposed algorithm has better performance in convergence speed, and the cooperative localisation precision can be guaranteed.
Influenza virus infections can lead to a number of secondary complications, including sepsis. We applied linear regression models to mortality and hospital admission data coded for septicaemia from 1998 to 2019 in Hong Kong, and estimated that septicaemia was associated with an annual average excess mortality rate of 0.23 (95% CI 0.04–0.40) per 100 000 persons per year and an excess septicaemia hospitalisation rate of 1.73 (95% CI 0.94–2.50) per 100 000 persons per year. The highest excess morbidity and mortality was found in older adults and young children, and during influenza A(H3N2) epidemics.
This study aimed to investigate the association of nasal nitric oxide and olfactory function.
A cross-sectional study was performed in 117 adults, including 91 patients with chronic rhinosinusitis and 26 healthy controls. Scores on the 22-item Sino-Nasal Outcomes Test, Lund-Mackay scale and Lund-Kennedy scale were recorded to assess severity of disease. All participants were screened for common inhaled and food allergens. Nasal nitric oxide and fractional exhaled nitric oxide testing, acoustic rhinometry and anterior rhinomanometry testing were performed to measure nasal function. The validated Sniffin’ Sticks test battery was used to assess olfactory function.
Higher nasal nitric oxide was an independent protective factor for odour discrimination and odour threshold in participants with chronic rhinosinusitis after adjusting for age, gender, drinking, smoking, 22-item Sino-Nasal Outcomes Test, Lund-Mackay score, Lund-Kennedy score, immunoglobulin E and the second minimal cross-sectional area by acoustic rhinometry. Nasal nitric oxide also showed high discrimination in predicting impaired odour discrimination. In addition, nasal nitric oxide was lower in older participants, those with higher Lund-Mackay or Lund-Kennedy scores and higher with elevated total serum immunoglobulin E concentrations above a threshold of 0.35 kU/l.
Higher nasal nitric oxide is associated with better odour discrimination in chronic rhinosinusitis and is modulated by age, degree of allergy and severity of chronic rhinosinusitis.
The capability of aircraft tyres to sustain landing impact loads is essential for flight landing safety. Hence, the development of a reliable experimental database is necessary to validate numerical models. The experimental data on aircraft tyre landing impact in the public literature are somewhat sparse. This paper describes a detailed design rig for aircraft tyre impact testing. A finite element model is then created and simulated using a finite element tool (ABAQUS). Inflation and static load simulations are analysed based on the FE tyre model to confirm its reliability. Comparison of experimental measurements with the results reveals that the model can predict the significant features of aircraft tyre impact in a landing scenario. Very little experimental data are publicly available to verify aircraft tyre models. Therefore, the experimental data in this paper fill this gap in the literature.
Lifestyle interventions are an important and viable approach for preventing cognitive deficits. However, the results of studies on alcohol, coffee and tea consumption in relation to cognitive decline have been divergent, likely due to confounds from dose–response effects. This meta-analysis aimed to find the dose–response relationship between alcohol, coffee or tea consumption and cognitive deficits.
Prospective cohort studies or nested case-control studies in a cohort investigating the risk factors of cognitive deficits were searched in PubMed, Embase, the Cochrane and Web of Science up to 4th June 2020. Two authors searched the databases and extracted the data independently. We also assessed the quality of the studies with the Newcastle-Ottawa scale. Stata 15.0 software was used to perform model estimation and plot the linear or nonlinear dose–response relationship graphs.
The search identified 29 prospective studies from America, Japan, China and some European countries. The dose–response relationships showed that compared to non-drinkers, low consumption (<11 g/day) of alcohol could reduce the risk of cognitive deficits or only dementias, but there was no significant effect of heavier drinking (>11 g/day). Low consumption of coffee reduced the risk of any cognitive deficit (<2.8 cups/day) or dementia (<2.3 cups/day). Green tea consumption was a significant protective factor for cognitive health (relative risk, 0.94; 95% confidence intervals, 0.92–0.97), with one cup of tea per day brings a 6% reduction in risk of cognitive deficits.
Light consumption of alcohol (<11 g/day) and coffee (<2.8 cups/day) was associated with reduced risk of cognitive deficits. Cognitive benefits of green tea consumption increased with the daily consumption.
To investigate the executive function and learning ability of the patients with first-episode schizophrenia, and its relationship with the patients’ clinical symptoms.
50 schizophrenia patients and 50 healthy controls were tested by the Tower of London (TOL). All the subjects received two phases of the test of TOL continuously, with a break of 1 minute. And Positive and Negative Symptom Scale (PANSS) was used to assess the clinical symptoms of the patients.
Compared with the control group, the number of reply during the 1st phase (x1) and the 2nd phase (x2)of the patients group, was lower (P<0.01); the reaction time during the 1st phase (t1) and the 2nd phase (t2) was longer (P<0.01); while the rate of correct answer during the 1st phase (p1) and the 2nd phase (p2) do not differ. For the control group, x2 was higher than x1 (P<0.01), and t2 was shorter than t1 (P<0.01). However, for the schizophrenia group, there were no difference between x1 and x2, t1 and t2. The value of x1, p1, x2 of the patients were correlated negatively with the PANSS negative subscale score (P< 0.05), and t1 and t2 were correlated positively with the the negative subscale score (P< 0.01). The performance of the TOL did not correlated with the PANSS positive subscale score and general psychopathology subscale score.
The executive function and learning ability of the schizophrenics are impaired and the impairment of the cognitive function is significantly correlated with the negative symptoms of schizophrenia patients.
Brain-derived neurotrophic factor (BDNF) gene may be involved in the pathogenesis of schizophrenia by virtue of its effects on neurotransmitter systems that are dysregulated in psychiatric disorder. The common functional polymorphism Val66Met (or rs6265) within the BDNF gene has been reported to be associated with age of onset in schizophrenia. We investigated the relationship between BDNF polymorphisms rs6265 and rs11030101 and early-onset schizophrenia in the Chinese population.
Subjects and methods
The tag single nucleotide polymorphisms (tag SNPs) rs11030101 and rs6265 in the BDNF gene were genotyped in 360 early-onset schizophrenics and 399 controls subjects. Single nucleotide polymorphism association and haplotype analysis were performed.
There were significant differences in allele and genotype frequencies between patient and normal control subjects for rs11030101 (χ2 = 5.130407, df = 1, p = 0.023553; χ2 = 6.121, df = 2, p = 0.047). No statistically significant differences were found in allele or genotype between patient and normal control subjects for rs6265. Stratification of the study by gender of the samples yielded significant evidence for an association with the polymorphisms rs11030101 in female population (genotype-wise: χ2 = 7.758, df = 2, p = 0.021).
Our study indicates that the BDNF play major roles in the susceptibility to early-onset and female schizophrenia in the Chinese population.
Cognitive dysfunction was thought to be one of the core features of schizophrenia. And the executive function of the patients was paid more attention by more and more researchers and clinicians.
To investigate the executive function and the learning ability of the patients with first-episode schizophrenia, and their relationships with psychiatric symptoms.
Fifty cases of first-episode schizophrenia patients and fifty age- and gender-matched healthy controls were tested by a computerized version of Tower of London (TOL) test. The scores of the Positive and Negative Syndrome Scale(PANSS) in the group of schizophrenia patients were over 60.
The numbers of the correct answer [x1 :(14.62 ± 4.12), x2: (14.80 ± 4.70)] during the first session and the second session of the TOL test of the patients group were significantly lower than that of the control group [x1: (17.48 ± 3.79), x2:(18.68 ± 3.19)], and the reaction times [t1: (9.27 ± 4.37) seconds, t2: (9.51 ± 5.58) seconds] of the two sessions of TOL were longer than the control group [t1: (7.28 ± 2.04) seconds, t2: (6.67 ± 1.51) seconds], P < 0.01. For the control group, x2 was significantly greater than x1, and t2 shorter than t1 (P < 0.01), while for the patients group, there was no difference between the performances of the first session and the second session. The scores of TOL in the schizophrenia patients were correlated with the negative symptom score of PANSS (P < 0.05) and were not correlated with the scores of other subscales of PANSS (P > 0.05).
The executive function and the learning ability of schizophrenia are impaired and the cognitive dysfunction is correlated with negative symptoms.
Schizophrenia is a chronic and severe mental illness which is characterized by the development of various detrimental clinical features, and its etiology still remains unknown. Based on the evidence from neurobiological and pharmacological research, dysfunctions in central serotonergic transmission may be involved in the development of schizophrenia. Tryptophan hydroxylase 2 (TPH2), a newly identified isoform of tryptophan hydroxylase (the rate limiting enzyme in the biosynthesis of serotonin), regulates the brain-specific serotonin synthesis.
To further clarify the role of TPH2 in the development of schizophrenia.
We performed a case-control study to examine the association of the TPH2 gene with schizophrenia and its clinical features.
We genotyped three putative functional polymorphisms (rs4570625, rs7305115 and rs4290270) within the gene and carried out a case-control study consisting of 304 schizophrenia patients and 362 healthy subjects. The severity of psychotic symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS).
The frequencies of genotypes and alleles of rs4570625, rs7305115 and rs4290270 did not differ significantly between schizophrenic patients and controls. However, the PANSS positive symptom subcore was significantly associated with rs4570625 (P = 0.022).
These results suggest that rs4570625 of TPH2 may play an important role in the development of positive symptoms in Han Chinese schizophrenic patients.
To explore the factors associated with occurrence of suicidal risk after treatment of Selective Serotonin Reuptake Inhibitor (SSRI) in bipolar disorder with their first depressive episode.
One hundred and seventy seven bipolar patients were enrolled in this retrospective study. Demographic and clinic features between non-occurrence of suicidal risk group and occurrence of suicidal risk group were compared. Stepwise Logistic regression model was used to identify the associated factors. Concordance statistics (i.e. the area under the ROC curve) was used to compute the discrimination of the associated factors, and Hosmer-Lemeshow goodness-of-fit statistic was used to measure the goodness-of-fit.
One hundred and fifty four patients were included in non-occurrence of suicidal risk group, while twenty three were included in occurrence of suicidal risk group. Clinical features associated with occurrence of suicidal risk after treatment of SSRI in bipolar disorder were as follows: symptom of irritability (OR=4.04, 95 CI:1.40-11.67) and psychotic symptom (OR=6.23, 95 CI:1.40-27.56).
This study demonstrated indicated that psychotic symptom and symptom of irritability were associated with occurrence of suicidal risk after treatment of SSRI in bipolar disorder, and it suggested that these two symptoms might be potential to be the predictors of occurrence of suicidal risk after treatment of SSRI in bipolar disorder.
Menopausal syndrome has been reported to be a worldwide women's mental health problem. Aborigines in rural areas have poorer access to mental health services. Thus, it is important to evaluate such symptoms of female aborigines with different menopausal statuses and their association with depression.
The aim of the study is to evaluate the association between physiological menopausal symptoms and depression during different menopausal period among female Taiwanese aborigines.
A total of 672 Taiwanese aboriginal women, aged 40–60, were recruited in the interviewing study and classified as pre-, peri-, and postmenopausal according to menstrual bleeding patterns in the previous 12 months. Then, the postmenopausal symptoms, depression, self-perceived health, family support, and associated demographic variables were assessed by questionnaire based on the results of interviewing by research assistants.
The results revealed that perimenopausal statuses were associated with depression and women with a perimenopausal status had a higher prevalence of depression than those with a premenopausal status. A higher score on physiological postmenopausal symptoms was found to be significantly associated with depression. Furthermore, somatic symptoms were associated with depression for pre-, peri-, and postmenopausal statuses. Moreover, sexual dysfunction and vasomotor symptoms were associated with depression only in the premenopausal status and postmenopausal status, respectively.
Depression should be routinely evaluated for female Taiwanese aborigines consulting with physicians for menopause symptoms, especially for somatic symptoms. Furthermore, attention should be provided to premenopausal women with sexual dysfunction and postmenopausal women with vasomotor symptoms for depression.
Multiple neurotrophic factors, including vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF)-2, nerve growth factor (NGF) and insulin-like growth factor(IGF)-1, have been shown to play important roles in the pathophysiology of mood disorders. However, insufficient clinical data supporting the importance of these neurotrophic factors in mood disorders, especially manic episode, have made inconclusive to make a connection between these factors and the disorder.
This study intended to investigate possible peripheral biomarkers in serum of manic episode of bipolar disorder.
We aimed to investigate whether or not serum levels of VEGF, FGF-2, NGF and IGF-1 varied in manic state.
Serum levels of VEGF, FGF-2, NGF and IGF-1 were examined in 70 drug-naïve patients with manic episode of bipolar disorder (BM) as well as 50 healthy controls, using an ELISA method.
The mean serum levels of VEGF, FGF-2, NGF and IGF-1 were 168.13±225.61pg/ml, 279.09±378.62pg/ml, 61.38±171.67pg/ml and 162.01±72.00ng/ml in BM patients, and 140.80±143.71pg/ml, 275.46±235.29pg/ml, 36.34±15.14pg/ml and 138.90±80.11ng/ml in healthy controls, respectively. Serum levels of FGF-2, NGF and IGF-1 in patients were significantly higher than those in healthy controls (Z=−2.896, P=0.004; Z=− 2.050, P=0.040; Z=−2.188, P=0.029; respectively), although there was no statistical difference in the serum levels of VEGF between two groups (Z=-0.468, P=0.639). Moreover, serum levels of NGF in patients correlated with the duration of disorder (rs=−0.241, P=0.044).
The increase in serum levels of FGF-2, NGF and IGF-1 in manic state may reflect a neuroprotective role for these factors, and these factors may be considered biological markers for manic episode.
Increasing evidence supports that 5HTTLPR polymorphism of the serotonin transporter gene(5HTTLPR) might associate to bipolar disorder and affective temperaments as measured by TEMPS-A. But the results are discrepant, furthermore, there are no data from Chinese population.
The present study was designed to investigate association between 5HTTLPR and bipolar disorder and affective temperaments of patients with bipolar disorder in the specific Chinese population and add new evidence to the field.
There hundred and five patients with bipolar disorder and 272 normal controls were included in the present case-control study⌧Temperament Evaluation of Memphis, Pisa, Paris and San Diego -autoquestionnaire version (TEMPS-A) in Chinese was used to assess affective temperament. Chi-square test, T test, Nonparametric test and ANOVA were employed to explore association between 5HTTLPR polymorphism and bipolar disorder and affective temperament of patients with bipolar disorder.
5-HTTLPR L/S polymorphism was associated with bipolar disorder in female (genotype χ2 = 6.769⌧P = 0.034⌧allele χ2 = 6.028⌧P = 0.014) and the S allele was associated with anxious temperament (t = 8.248⌧P = 0.005) in patients with bipolar disorder. the LA allele of 5-HTTLPR rs25531 A/G polymorphism was associated with hyperthymic temperament in patients with bipolar disorder (Z = −2.205⌧P = 0.027).
5-HTTLPR might have an effect on the prevalence of bipolar disorder in female and regulate affective temperaments of patients with bipolar disorder in some degree in Chinese population.