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This paper presents the integration and channel characterization of a highly integrated dual-band digital beamforming space-borne synthetic aperture radar (SAR) receiver. The proposed SAR sensor is a low-cost, lightweight, low-power consumption, and dual-band (X/Ka) dual-polarized module ready for the next-generation space-borne SAR missions. In previous works, by the authors, the design and experimental characterization of each sub-system was already presented and discussed. This work expands upon the previous characterization by providing an exhaustive experimental assessment of the fully integrated system. As it will be shown, the proposed tests were used to validate all the instrument channels in a set-up where the SAR sensor was illuminated by an external source minim the ground reflected waves. Test results demonstrate how the system channels are properly operating allowing the reception of the input signals and their processing in the digital domain. The possibility to easily implement a calibration procedure has also been validated to equalize, in the digital domain, the unavoidable amplitude differences between the different channels.
Surface modification of titanium and titanium alloys is a common method to improve anchoring of bone tissue and implants in hard tissue engineering applications. In the current work, a combination of chemical and physical methods (anodization and physical vapor deposition) was used to roughen the titanium surface and deposit iron (Fe) on the surface of titanium at different thicknesses. The optimized thickness of 100 Å was selected for mechanical and biological characterization. We found that anodization increases the surface roughness of Ti from 21 ± 0 to 229 ± 9 nm, whereas Fe deposition does not change it significantly. Our results also showed that surface modification of Ti by anodization increases the proliferation of osteosarcoma cells at both time points, whereas Fe-deposited samples showed the lowest cellular activity. These results suggest that Fe-deposited Ti implants may be suitable candidates for patients with osteosarcoma, as the proliferation of malignant cells decreases in the presence of Fe.
The coronavirus disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2 virus) has been sustained in China since December 2019, and has become a pandemic. The mental health of frontline medical staff is a concern. In this study, we aimed to identify the factors influencing medical worker anxiety in China during the COVID-19 outbreak. We conducted a cross-sectional study to estimate the prevalence of anxiety among medical staff in China from 10 February 2020 to 20 February 2020 using the Zung Self-rating Anxiety Scale (SAS) to assess anxiety, with the criteria of normal (⩽49), mild (50–59), moderate (60–70) and severe anxiety (⩾70). We used multivariable linear regression to determine the factors (e.g. having direct contact when treating infected patients, being a medical staff worker from Hubei province, being a suspect case) for anxiety. We also used adjusted models to confirm independent factors for anxiety after adjusting for gender, age, education and marital status. Of 512 medical staff in China, 164 (32.03%) had had direct contact treating infected patients. The prevalence of anxiety was 12.5%, with 53 workers suffering from mild (10.35%), seven workers suffering from moderate (1.36%) and four workers suffering from severe anxiety (0.78%). After adjusting for sociodemographic characteristics (gender, age, education and marital status), medical staff who had had direct contact treating infected patients experienced higher anxiety scores than those who had not had direct contact (β value = 2.33, confidence interval (CI) 0.65–4.00; P = 0.0068). A similar trend was observed in medical staff from Hubei province, compared with those from other parts of China (β value = 3.67, CI 1.44–5.89; P = 0.0013). The most important variable was suspect cases with high anxiety scores, compared to non-suspect cases (β value = 4.44, CI 1.55–7.33; P = 0.0028). In this survey of hospital medical workers during the COVID-19 outbreak in China, we found that study participants experienced anxiety symptoms, especially those who had direct clinical contact with infected patients; as did those in the worst affected areas, including Hubei province; and those who were suspect cases. Governments and healthcare authorities should proactively implement appropriate psychological intervention programmes, to prevent, alleviate or treat increased anxiety.
Tooth enamel, the outermost layer of human teeth, is a complex, hierarchically structured biocomposite. The details of this structure are important in multiple human health contexts, from understanding the progression of dental caries (tooth decay) to understanding the process of amelogenesis and related developmental defects. Enamel is composed primarily of long, nanoscale crystallites of hydroxyapatite that are bundled by the thousands to form micron-scale rods. Studies with transmission electron microscopy show the relationships between small groups of crystallites and X-ray diffraction characterize averages over many rods, but the direct measurement of variations in local crystallographic structure across and between enamel rods has been missing. Here, we describe a synchrotron X-ray-based experimental approach and a novel analysis method developed to address this gap in knowledge. A ~500-nm-wide beam of monochromatic X-rays in conjunction with a sample section only 1 μm in thickness enables 2D diffraction patterns to be collected from small well-separated volumes within the enamel microstructure but still probes enough crystallites (~300 per pattern) to extract population-level statistics on crystallographic features like lattice parameter, crystallite size, and orientation distributions. Furthermore, the development of a quantitative metric to characterize relative order and disorder based on the azimuthal autocorrelation of diffracted intensity enables these crystallographic measurements to be correlated with their location within the enamel microstructure (e.g., between rod and interrod regions). These methods represent a step forward in the characterization of human enamel and will elucidate the variation of the crystallographic structure across and between enamel rods for the first time.
This paper presents a novel dual-band (DB) dual-polarized (DP) shared aperture antenna with high isolation by using a combination of microstrip dipoles and dielectric resonator antennas (DRAs) for S and C bands, respectively. In the S band, two sets of proximity coupled stacked microstrip dipoles which crossed at the center are employed to achieve dual-linear polarization (DLP) and obtain desired bandwidth (BW), isolation, and pure polarization. The rectangle DRA with hybrid feed is selected as the C band element for its advantages of small base area and high isolation, and a 2 × 2 array is presented with the “pair-wise” anti-phase feed technique to achieve a low cross-polarized level. Moreover, benefited from the back feed scheme, the proposed antenna has a symmetrical structure and has the potential of expanding into a larger aperture. The proposed antenna has been manufactured and measured, and the results agree well with simulations, which prove the validity of the proposed design.
We present a long-term seasonal tree ring cellulose oxygen isotope (δ18Oc) time series created by analyzing four segments (S1, S2, S3, and S4) per year during the period of 1951–2009 from southeastern Tibetan Plateau. This intraseasonal δ18Oc reveals the onset and mature phase of the summer monsoon precipitation in this region. Analysis indicates that the δ18Oc of S1 has the strongest correlation with precipitation during the regional monsoon onset (29–33 pentads, May 21–June 10, r = −0.69), and the δ18Oc values for S2, S3, and S4 correlate strongly with June, July, and August precipitation, respectively. Combined δ18Oc of S2, S3, and S4 shows the most robust correlation (r = −0.82) with the mature-phase monsoon precipitation (June-July-August, JJA), passing rigorous statistical tests for calibration and verification in dendroclimatology. These results demonstrate the feasibility in using long-term intraseasonal δ18Oc to reconstruct the Asian summer monsoon's intraseasonal variations.
To compare efficacy and medical costs of typital and atypical antipsychotics in treating schizophrenic patients.
250 in patients in general hospital and psychiatric hospital were randomly allocated to one of the two groups, one treated with typital antipsychotics as chlorpromazine, haloperidol and so on with a mean daily dose of 500∼800 mg in chlorpromazine equivalents, and the other with atypical agents in cluding clozapine (mean daily dose of 400∼800mg ), risperidone of 6 mg, or olanzapine of 20 mg.
The total costs of the treatment were (3157±253) Yuan RMB for patients treated with typical agents in general hospital, and (3673±294) Yuan RMB for patients treated with typical agents in psychiatric hospital respectively. the costs for medicine were (774±903) Yuan RMB, (1061±903) Yuan RMB respectively. the costs in atypical group were(1120±390) Yuan RMB and (1637±325) Yuan RMB, and (108±157) Yuan RMB and (240±317) Yuan RMB respectively. the duration of patients treated with typical agents in hospital is longer than that with atypical agents.
It indicates that atypical antipsychotics have similar efficacy to typical agents in treating schizophrenic patients with less costs.
Many studies showed the differences in subjective response to sexual stimuli between heterosexual and homosexual men. However, the underlying neurobiological factors of sexual orientation are largely unknown. We addressed the question what is the major attribution of the expected differences in brain activation, i.e. neural circuits or different cognitive process. Twenty-eight healthy male volunteers, 14 heterosexuals and 14 homosexuals, were scanned by functional Magnetic Resonance Imaging while subjects were viewing different types of stimuli, i.e. heterosexual couple stimuli (HCS), gay couple stimuli (GCS), lesbian couple stimuli (LCS) and neutral stimuli (NS). SPM02 was used for data analysis. Rating of sexual attractiveness was assessed. Subjective sexual arousal was induced by HCS and GCS in heterosexual and homosexual men, respectively. And sexual disgust was induced by GCS and LCS in heterosexual and homosexual men, respectively. As compared to viewing NS, viewing sexual stimuli induced significant different brain activations most of which had characteristic for cognitive process. These observations suggested that different cognitive pattern was major attribution of different subjective response to sexual stimuli between heterosexual and homosexual men.
The treatment of refractory schizophrenia has been a clinical challenge for most psychiatrists. The possible mechanism of the refractory schizophrenia included diagnostic errors, medical conditions and brain dysgensis. Here, we described a patient with childhood-onset schizophrenia who had severe psychiatric symptoms such as auditory hallucination and persecutory delusion and so on. We reexamined all his possible medical conditions and found the patient had an abnormal enlarged Cavus Septum Pellucidum (CSP) combined with Cavum Vergae (CV) (maximum length>30 mm). Some reports suggested that abnormal CSP(length>6 mm) has an significant association with schizophrenia. However, abnormally large CSP or CSP/CV and related prognosis were reported rarely. This case suggested that abnormally enlarged CSP or CSP/CV may lead to schizophrenia and worse prognosis.
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3′-untranslated region of the CLDN5 locus was associated with schizophrenia (χ2 = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5′-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (χ2) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (χ2 = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors.
To investigate the effect of Chinese herb Danshen-Dahuang on learning and memory ability in rats with Alzheimer disease (AD) induced by D-galactose and AlCl3 and its possible mechanisms.
The AD model was produced by injecting D-galactose and AlCl3 intraperitoneally for 90 days. Since the 20th day of D-galactose and AlCl3 intraperitoneal injection, the rats in Danshen-Dahuang group had been treated with Danshen-Dahuang extraction by intragastric administration for 70 days. Subsequently,learning and memory ability of the mice was evaluated by Morris water maze and hippocampal gene expression of APP, PS1 was tested by reverse transcription polymerase chain reaction (RT-PCR).
Rats intragastric administration with Danshen-Dahuang, mice had shorter latency (P< 0.05) and less error times (P< 0.05) in water maze test compared with those in AD model group. At the same time, Danshen-Dahuang down regulated the expression of APP, PS1 mRNA (P< 0.05) in hippocampus.
Danshen-Dahuang improves the learning and memory ability of AD rats, its mechanism may be related to the downregulated expression of APP, PS1 mRNA.
To study on mental health status of the freshman and graduates in five different universities.
The 1022 freshman and 956 college graduates from five different universities were tested with the Symptom Checklist 90 (SCL-90). They came from one was general university, two technological universities, one is medical university, one is agricultural university.
All of the freshman and college graduates’ mental health status is inferior to the contemporaries; there are about 8.5% freshman and 11.4% graduates who have psychological problems. the SCL-90 factor scores of liberal arts students are higher than those of the science in freshman and graduates. There is significant difference between two groups (P< 0.05~P< 0.01). among the five different universities, freshman is same, but in graduates of five different universities, medical graduates have a better mental health status than other college's students do.
It is necessary that positive educating mental health status to college students’ and trained always-cheerful character and stable mood so level of mental health status of college freshman and graduates will be improved.
To study on Personal Characteristics of the freshman and graduates in five different universities.
The 1022 freshman and 956 graduates from five different universities were tested with the Eysenck Personality Questiornaire (EPQ). They came from one was general university, two technological universities, one is medical university, one is agricultural university.
Distribution of freshman and graduates personal characteristics in various sexes and universities is different. There are 19% and 12% of freshman with some psychological problem were P type and N type respectively according to neuroticism scale of EPQ, 64% of that were unstable temperament; 31% of the freshman who were unstable temperament and 25% were mental health status was extroversion disposition. But in graduates are 42% and 34% ( P type and N type) respectively according to neuroticism scale of EPQ. Unstable temperament is 58% and mental health status was extroversion disposition is 39%.
The freshman and graduates psychological health of Shanxi Province of China is poor and should be paid more attention. the psychological state is related to different universities. the freshman and graduates are associated with personal characteristics, unstable professions, emotional trouble and passive attitude to the value and so on.
An increasing number of studies have described the relationship between velo-cardio-facial syndrome (VCFS) and schizophrenia. in a family-based study, we found that rs10314, a single nucleotide polymorphism (SNP) present in the 3’-flanking region of the CLDN5 gene, was associated with schizophrenia among a Chinese population. High false positive rate is a common problem with the association study of human diseases. It is very important to replicate an initial finding with different samples and experimental designs.
A total of 749 patients with schizophrenia and 383 age and sex matched healthy control subjects in Chinese population were recruited. PCR-based RFLP protocol was applied to genotype rs10314 to see its disease association.
The χ2 goodness-of-fit test showed that the genotypic distributions of rs10314 were in Hardy-Weinberg equilibrium in both the patient group (χ2=1.12, P=0.289) and the control group (χ2=0.22, P=0.639). rs10314 was associated with schizophrenia with an odds ratio (OR) of 1.32 in the male subjects (χ2=5.45, P=0.02, 95% CI 1.05-1.67) but not in the female subjects (χ2=0.64, P=0.425, OR=1.14, 95% CI 0.83-1.57). the χ2 test showed a genotypic association only for combined samples (χ2=7.80, df=2, P=0.02). SNP rs10314 is a G to C base change. Frequency of the genotypes containing the C allele was significantly higher in the patient group than in the control group.
The present work shows that the CLDN5 gene polymorphism is more likely to be involved in schizophrenic men than women, suggesting that this gene may contribute to the gender differences in schizophrenia.
Metabolic syndrome induced by atypical antipsychotics is more prevalence in schizophrenic patients. Much less is known regarding paliperidone ER. The objective of this study was to compare matched paliperidone-ER- and olanzapine-treated schizophrenic patients on measures of glucose and lipid metabolism. Eighty hospitalized patients with schizophrenia (DSM-) were randomly assigned to treatment with paliperidone ER or olanzapine for 12 weeks. At baseline and every 4 weeks, we assessed weight, subcutaneous fat, waist and hip circumferences, fasting glucose, insulin, glycohemoglobin A1, cholesterol, triglycerides, high density level (HDL) cholesterol, low density level (LDL) cholesterol and prolactin. And we also evaluate the body mass index (BMI), homeostasis insulin resistance (HOMA-IR) and homeostasis β-cell function (HOMA-B). 33 patients randomly assigned to paliperidone ER and 23 patients randomly assigned to olanzapine completed the entire 12-week treatment. Within-group overall analysis showed that the fasting measures were increased in weight, BMI, waist circumferences, hip circumferences, subcutaneous fat, cholesterol, triglyceride and prolactin for two groups, and fasting glucose, LDL and HOMA-B were increased for olanzapine group. There was significantly difference in serum prolactin between paliperidone ER and olanzapine group. And there was a trend for HOMA-B to increase in olanzapine group over 12 weeks compared to paliperidone ER group. However, there were no overall differential drug effects over 12 weeks on the fasting measures of BMI, glucose, glycohemoglobin A1, insulin, HDL, LDL, cholesterol, triglyceride and HOMA-IR. The study further reinforces the necessity of regular monitoring the metabolic parameters in schizophrenic patients with atypical antipsychotics including paliperidone ER.
This double-blind (DB), relapse prevention, phase-3 study was designed to evaluate the efficacy and safety of paliperidone palmitate long-acting 3-monthly formulation (PP3M) versus placebo in delaying time-to-relapse of schizophrenia symptoms.
Adults (18-70 years old) with schizophrenia (DSM-IV-TR) were treated with PP (17-week, open-label [OL] transition phase: 50, 75, 100, or 150 mg eq, once-monthly, [PP1M]; 12-week OL maintenance phase: 3.5-fold PP1M stabilized dose, single injection), and then randomized (1:1) to PP3M fixed doses (175, 263, 350 or 525 mg eq.) or placebo.
305/506 patients enrolled were randomized (PP3M: n=160; placebo: n=145); majority were men (75%), white (59%), mean age 38.4 years. Interim analysis results favored PP3M vs. placebo (p = 0.0002, two-sided log-rank test; HR: 3.45, 95% CI: 1.73; 6.88); median time-to-relapse was 274 days in placebo and not estimable in PP3M group. Final results were consistent with interim analysis. Both PANSS total score and CGI-S score showed a significant effect over time in PP3M- vs. placebo-treated patients (p>0.001). 330/506 (65.2%) patients in OL phase and 183/305 (60.0%) in DB phase (PP3M: 61.9% vs. placebo: 57.9%) had ≥1 treatment-emergent adverse event (TEAE). The TEAEs noted more frequently in PP3M-vs. placebo (DB phase) were nasopharyngitis (5.6% vs. 1.4%), weight gain (8.8% vs. 3.4%), headache (8.8% vs.4.1%) and akathisia (4.4% vs. 0.7%).
Compared with placebo, PP3M significantly delayed time to first relapse in patients with schizophrenia, previously treated for 4 months with PP1M. PP3M was tolerable with a safety profile generally consistent with other marketed formulations of paliperidone.
The majority of neuroimaging studies reported smaller hippocampal volumes in patients with posttraumatic stress disorder (PTSD). Our previous study found that PTSD is associated with selective volume loss of the CA3/dentate gyrus subfields However, the causality of smaller hippocampal volumes and PTSD cannot be determined in these studies because of the cross-sectional nature of them. The purpose of this longitudinal study was to determine if PTSD caused hippocampal subfields volume loss following traffic accidents. Volumes of hippocampal subfields in thirty seven traffic accident survivors were measured using 3T MRI in one week after accident, and twenty five of them completed one year follow-up MRI scan. Fourteen participants met the PTSD diagnosis in one year follow-up while other eleven did not met PTSD diagnosis criteria. PTSD was significantly associated with volumes reduction of CA3/dentate gyrus subfield (β=0.244 p=0.017) while other subfields were spared. It also shown volume loses of Entorhinal Cortex (ERC) of both side in one year follow-up for the whole sample (mean volume reduction: right 19.25mm3, left 22.04 mm3). But no association has been found between PTSD and ERC volume alteration. The findings indicate for the first time in humans that selective volume loss of the CA3/dentate gyrus subfields is the results but not the risk factor of PTSD. It also suggested that ERC may also be a stress sensitive region.
Recent imaging studies have shown that brain morphology and neural activity during sexual arousal differ between homosexual and heterosexual men. Whether the structural and task-related functional differences also exist in the resting state is unknown. The purpose of the study is to characterize the association of homosexual preference with measures of regional homogeneity and functional connectivity in the resting state. Participants were 26 homosexual men and 26 age-matched heterosexual men. The sexual orientation of every participant was evaluated using the Kinsey Scale. We first assessed group differences in regional homogeneity and then, taking the identified differences as seed regions, we compared groups in measures of functional connectivity from those seeds. The behavioral significances of the differences in regional homogeneity and functional connectivity were assessed by examining their associations with scores on the Kinsey Scale. Homosexual participants showed significantly reduced regional homogeneity in the left inferior occipital gyrus, right middle occipital gyrus, right superior occipital gyrus, left cuneus, right precuneus, and increased regional homogeneity in the rectal gyrus, bilateral midbrain, and left temporal lobe. Regional homogeneity correlated positively with Kinsey scores in the left inferior occipital gyrus. The homosexual group also showed reduced functional connectivity in left middle temporal gyrus, left supra-marginal gyrus and right cuneus. In addition, the connection between the left inferior occipital gyrus and right thalamus in the homosexual group was correlated positively with Kinsey scores. This differences in homogeneity and fucntional connectivity may contribute to a better understanding of the neural basis of male sexual orientation.