Search

Fluid-attenuated inversion recovery vascular hyperintensity (FVH) is frequently observed in patients with acute ischemic stroke (AIS). FVH is associated with functional outcome at 3 months in AIS patients receiving endovascular thrombectomy. In the present study, we assessed whether FVH predicted early neurological deterioration (END) and hemorrhagic transformation (HT) within 72 h in AIS patients receiving endovascular thrombectomy. We retrospectively analyzed 104 patients with acute internal-carotid-artery or proximal middle-cerebral-artery occlusion within 16 h after symptom onset. Before thrombectomy, all patients underwent brain magnetic resonance imaging. END was defined as an increase of 4 points or more from baseline National Institutes of Health Stroke Scale (NIHSS) during 72 h following onset. HT was assessed by brain computed tomography. Statistical analyses were performed to predict END and HT. The proportion of high FVH score, high American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grade in non-END group was higher than that in END group (p 0.001, p 0.001, respectively). FVH score was positively correlated with ASITN/SIR grade (r = 0.461, p 0.001). FVH score was a predictor factor for END (adjusted OR, 13.552; 95% CI, 2.408-76.260; p = 0.003), while FVH score was not a predictor factor for HT. Furthermore, NIHSS at admission (adjusted OR, 1.112; 95% CI, 1.006-1.228; p = 0.038) and high-density lipoprotein cholesterol (adjusted OR, 18.865; 95% CI, 2.998-118.683; p = 0.002) were predictor factors for HT. To assess FVH score before thrombectomy might be useful for predicting END in AIS patients receiving endovascular thrombectomy.

Dopamine depletion and microstructural degradation underlie the neurodegenerative processes in Parkinson’s disease (PD). To explore early alterations and underlying associations of dopamine and microstructure in PD patients utilizing the hybrid positron emission tomography (PET)-magnetic resonance imaging (MRI). Twenty-five PD patients in early stages and twenty-four matched healthy controls underwent hybrid 18F-fluorodopa (DOPA) PET-diffusion tensor imaging (DTI) scanning. The striatal standardized uptake value ratio (SUVR), DTI maps (fractional anisotropy, FA; mean diffusivity, MD) in subcortical grey matter, and deterministic tractography of the nigrostriatal pathway were processed. Values in more affected (MA) side, less affected (LA) side and mean were analysed. Correlations and mediations among PET, DTI and clinical characteristics were further analysed. PD groups exhibited asymmetric pattern of dopaminergic dysfunction in putamen, impaired integrity in the microstructures (nigral FA, putaminal MD, and FA of nigrostriatal projection). On MA side, significant associations between DTI metrics (nigral FA, putaminal MD, and FA of nigrostriatal projection) and motor performance were significantly mediated by putaminal SUVR, respectively. Early asymmetric disruptions in putaminal dopamine concentrations and nigrostriatal pathway microstructure were detected using hybrid PET-MRI. The findings further implied that molecular degeneration mediates the modulation of microstructural disorganization on motor dysfunction in the early stages of PD., To explore early alterations and underlying associations of dopamine levels and microstructure in Parkinson’s Disease (PD), Shang et al use a hybrid positron emission tomography (PET)-magnetic resonance imaging (MRI) approach in early stage patients and age-matched controls. Their data implies that molecular degeneration mediates the effects of microstructural disorganization on motor dysfunction in the early stages of PD.

Stroke-associated infection (SAI) is a major medical complication in acute ischemic stroke patients (AIS) treated with endovascular therapy (EVT). Three hundred thirty-three consecutive patients with AIS caused by a large vessel occlusion in the anterior circulation who received EVT (142 (42.6%) of them were given IV tPA as bridging therapy) and 337 AIS patients who received IV tPA only (non-EVT) were enrolled in the study and evaluated to determine the association of inflammatory factors on admission with SAI. Among the 333 AIS patients undergoing EVT, SAI occurred in 219 (65.8%) patients. Patients with SAI had higher baseline National Institutes of Health Stroke Scale (NIHSS) total scores, white blood cell (WBC) and neutrophil counts, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) than those without SAI (P

Inflammatory damage plays an important role in cerebral ischemic pathogenesis and represents a new target for treatment of stroke. Berberine is a natural medicine with multiple beneficial biological activities. In this study, we explored the mechanisms underlying the neuroprotective action of berberine in mice subjected transient middle cerebral artery occlusion (tMCAO). Male mice were administered berberine (25, 50 mg/kg/d, intragastric; i.g.), glycyrrhizin (50 mg/kg/d, intraperitoneal), or berberine (50 mg/kg/d, i.g.) plus glycyrrhizin (50 mg/kg/d, intraperitoneal) for 14 consecutive days before tMCAO. The neurological deficit scores were evaluated at 24 h after tMCAO, and then the mice were killed to obtain the brain samples. We showed that pretreatment with berberine dose-dependently decreased the infarct size, neurological deficits, hispathological changes, brain edema, and inflammatory mediators in serum and ischemic cortical tissue. We revealed that pretreatment with berberine significantly enhanced uptake of (18)F-fluorodeoxyglucose of ischemic hemisphere comparing with the vehicle group at 24 h after stroke. Furthermore, pretreatment with berberine dose-dependently suppressed the nuclear-to cytosolic translocation of high-mobility group box1 (HMGB1) protein, the cytosolic-to nuclear translocation of nuclear factor kappa B (NF-κB) and decreased the expression of TLR4 in ischemic cortical tissue. Moreover, co-administration of glycyrrhizin and berberine exerted more potent suppression on the HMGB1/TLR4/NF-κB pathway than berberine or glycyrrhizin administered alone. These results demonstrate that berberine protects the brain from ischemia–reperfusion injury and the mechanism may rely on its anti-inflammatory effects mediated by suppressing the activation of HMGB1/TLR4/NF-κB signaling.

As a recently identified bioactive peptide of brain renin-angiotensin system (RAS), angiotensin-(1-7) [Ang-(1-7)] along with its metabolic enzyme angiotensin-converting enzyme (ACE) 2 and its receptor Mas forms ACE2/Ang-(1-7)/Mas axis. Accumulating evidence suggests an essential role of ACE2/Ang-(1-7)/Mas axis in maintaining normal cognitive functions in both animals and human subjects, and dysregulation of this axis contributed to the pathogenesis of several neurodegenerative diseases such as hypertension-induced neurodegeneration and vascular dementia. To date, whether this axis was associated with the etiology and progression of Alzheimer's disease (AD), the most prevalent neurodegenerative disease in the elderly, remains unclear. In the current study, by using senescence-accelerated mouse prone 8 (SAMP8) mice, an animal model of sporadic AD, we showed for the first time that the level of Ang-(1-7) in the brain was significantly reduced during disease progression. More importantly, an inverse correlation was found between Ang-(1-7) level and tau hyperphosphorylation, a pathological hallmark of AD, in cerebral cortex and hippocampus of SAMP8 mice. Meanwhile, this has been further confirmed in P301S mice, an animal model of pure tauopathy. All these findings suggested that Ang-(1-7), the main effector of brain ACE2/Ang-(1-7)/Mas axis, might be implicated in the etiology and progression of AD, possibly via modulation of tau hyperphosphorylation.

We recently revealed that p.H157Y (rs2234255), a rare coding variant of triggering receptor expressed on myeloid cells 2 gene (TREM2), was associated with Alzheimer's disease (AD) susceptibility in Han Chinese. Contrastingly, although p.H157Y was previously identified in both AD cases and controls by several sequencing studies, no association of this variant with disease susceptibility was reported. To gain a credible conclusion on the association between p.H157Y and AD risk, a meta-analysis involving 7,102 cases and 7,408 controls was conducted. Our results indicated that p.H157Y was associated with an increased risk of AD (OR=3.65, 95% CI: 1.61-8.28; P=0.002), further establishing TREM2 as an important susceptibility gene for this disease.

Radial basis function (RBF) neural network has excellent local mapping and function approximation ability, which is suitable for achieving the optimal solution of nonlinear equations. Due to the direction of the light source is not being estimated accurately by the traditional shape from shading algorithm, in this paper, the RBF neural network is introduced to optimize the classic problem. A RBF reflection model is established to replace the ideal Lambertian reflection model. Then the classic images and two real images are processed using this model without the need of the initial information of the light source. The restored 3D results show that the improved algorithm works better in the details than the traditional algorithm. The errors are much smaller. By adjusting the relevant parameters in RBF reflection model automatically, the training process has been shortened and the convergence rate is improved at the same time.

It is unclear whether previous statin therapy influences the prognosis, hemorrhagic transformation, and plasma matrix metalloproteinases (MMP)-9 levels in Chinese stroke patients receiving intravenous thrombolysis. We conduct a prospective cohort study of 193 patients treated with intravenous thrombolysis. All the enrolled patients were divided into 2 groups (the control group and the statin group), according to the previous history of statin use. The plasma MMP-9 levels were detected before and at 6 hours, 12 hours, 24 hours, and 72 hours after intravenous thrombolysis. The clinical outcome of stroke was measured in terms of the functional outcome and occurrence of symptomatic intracerebral hemorrhage. The MMP-9 levels increased after thrombolysis in statin group and control group. No significant intergroup difference was found in the MMP-9 levels before and at 6 hours after thrombolysis, but the levels were significantly lower in the statin group than in the control group at 12, 24, and 72 hours (P.001) after thrombolysis. Similarly, no significant intergroup difference was noted in the occurrence of symptomatic intracranial hemorrhage as was the case with the modified Rankin scale (assessed by the Mann-Whitney U test) at 7 days (P = .428) and 90 days (P = .419) after thrombolysis. Our results indicate that pretreatment with statin can inhibit the thrombolysis-induced increase in plasma MMP-9 levels but does not significantly affect the prognosis of acute ischemic stroke patients undergoing intravenous thrombolysis.

The probability distribution of electrical characteristic parameters of semiconductor device is an important reference which is used to analyze the reliability and quality consistency of devices. These distributions are considered as normal distribution at home and abroad. This paper utilized mature GaAs MESFET low noise amplifier as analytic sample which is volume production and wide application, and used high-precision Agilent B1505A device analyzer to test main electrical characteristics of 408 samples. After the distribution generation of test results, the Skewness-Kurtosis method was used to analyze probability distributions of the results. At last, the conclusion of distribution of measuring parameter is non-normal distribution was educed.

To evaluate the potential association between the plasma glucose levels and the 90-day prognosis in patients with spontaneous intracerebral hemorrhage (sICH).Patients with a well-defined diagnosis of sICH admitted within 24 h of onset were included. Random plasma glucose at admission and fasting plasma glucose on the following day were measured. Hyperglycemia was defined as a random plasma glucose ≥10 mmol/L or a fasting plasma glucose ≥7 mmol/L. Neurological severity at admission was assessed using the National Institutes of Health Stroke Scale (NIHSS). Functional outcomes were evaluated using modified Rankin Score (mRS) at three months after onset. Potential correlations between plasma glucose levels and neurological severity or functional outcomes values were assessed on Spearman's correlation analysis. Multivariable logistic regression analyses were performed to identify whether there were independent risk factors for 90-day outcomes after sICH.228 consecutive adult patients with a mean age of 62.4 ± 12.9 years were prospectively enrolled. No significant association was observed between the random glucose levels (r = 0.108, p = 0.146) or fasting glucose levels (r = 0.116, p = 0.098) with functional outcomes at 90 days after discharge. However, hyperglycemia was associated with the neurological severity of sICH, both random glucose levels （r = 0.183, p = 0.009）and fasting glucose levels (r = 0.133, p = 0.045). On logistic regression analyses, age and NIHSS values at admission were independently associated with poor outcomes.Hyperglycemia was associated with neurological severity of sICH, but not with 90-day outcomes.

Background and aim The severity of cerebral microbleeds (CMBs) affected the prognosis of patients with acute cerebrovascular disease. Considering the impact of CMBs on clinical decision, it is necessary to assess the risk factors of CMBs. We aimed to evaluate the independent risk factors of CMBs in patients with acute ischemic stroke of large-artery atherosclerosis. Materials and Methods 112 patients were enrolled in the study. The baseline information, the results of laboratory examination and cranial MRI were collected. The independent risk factors of CMBs in patients with acute ischemic stroke due to large-artery atherosclerosis were evaluated. Results CMBs were found in 56 (50%) patients. Older age and higher homocysteine (Hcy) level were associated with an elevated chance of occurrence of CMBs. Further, there was a positive correlation between CMBs grade and serum Hcy level. Conclusions Serum Hcy level is strongly associated with the presence of CMBs in patients with acute ischemic stroke due to large-artery atherosclerosis. Serum Hcy level may be a potential therapeutic target for alleviating adverse clinical outcomes of CMBs.

The tunable micro-cavity based on one-dimensional (1D) photonic crystal doped by KTP is designed. The optical transmission properties in the doped one-dimensional defect photonic crystals are analyzed using transfer matrix method (TMM). According to the electro-optic effect, the refractive index ellipsoid equation is established with the applied alternating current at both coordinate axes, and the characteristics of temperature-optics and modulation are studied. Numerical calculations and experimental results show that the tuning range is ∼40 nm.

A recent genome-wide association study conducted in Caucasians has identified glutaminyl-peptide cyclotransferase (QPCT) gene as a susceptibility gene for schizophrenia, as its common single nucleotide polymorphism (SNP) rs2373000 was significantly associated with the risk of this disease. To date, this finding has not been validated in other populations or ethnic groups. The aim of this study was to investigate the association of common SNPs spanning QPCT gene with the susceptibility of schizophrenia in a Han Chinese population comprising 440 schizophrenia patients and 450 control subjects. A total of 6 tagSNPs including rs2373000 was selected and then genotyped in our sample. Although the relation between rs2373000 and the risk of schizophrenia was not successfully replicated, we showed for the first time that the minor allele (C) of rs3770752 was associated with a reduced risk of schizophrenia (odds ratio (OR) = 0.645; 95 % confidence interval (CI) 0.486-0.855; P corrected = 0.012) in our cohorts. Meanwhile, this allele seemed to modify the schizophrenia risk through a dominant manner (CC + CT vs. TT, OR = 0.625; 95 % CI 0.457-0.854; P corrected = 0.03). In addition, we found that the minor allele (T) of rs3770748 remarkably reduced the schizophrenia risk via a recessive manner (TT vs. TC + CC, OR = 0.618; 95 % CI: 0.449-0.851; P corrected = 0.03). Taken together, these findings demonstrate a significant association between common SNPs within QPCT gene and schizophrenia risk in a Han Chinese population, suggesting QPCT gene may represent a susceptibility gene for this disease.

In this article, a considerable value of spontaneous emission factor is estimated based on the spontaneous emission radiation patterns in micro-cavity lasers. After the spontaneous emission for a dipole in the micro-cavity is studied, the confinements of vacuum fields and electrons are considered together for a quantum well in the micro-cavity laser. The TE mode and TM mode spontaneous emission spectra are presented for a single quantum well embedded in a planar micro-cavity laser at 300 K. The results show that the TE mode spontaneous emission spectrum is enhanced, whereas the TM mode spontaneous emission is suppressed greatly. The maximum values obtained for the spontaneous emission coupling factors are 0.2 and 0.0055 for a dipole and a quantum well planar micro-cavity laser with distributed Bragg reflectors, respectively.

In this work, we use a 3-nm-thick Al0.64In0.36N back-barrier layer in In0.17Al0.83N/GaN high-electron mobility transistor (HEMT) to enhance electron confinement. Based on two-dimensional device simulations, the influences of Al0.64In0.36N back-barrier on the direct-current (DC) and radio-frequency (RF) characteristics of InAlN/GaN HEMT are investigated, theoretically. It is shown that an effective conduction band discontinuity of approximately 0.5 eV is created by the 3-nm-thick Al0.64In0.36N back-barrier and no parasitic electron channel is formed. Comparing with the conventional InAlN/GaN HEMT, the electron confinement of the back-barrier HEMT is significantly improved, which allows a good immunity to short-channel effect (SCE) for gate length decreasing down to 60 nm (9-nm top barrier). For a 70-nm gate length, the peak current gain cut-off frequency (f T) and power gain cut-off frequency (f max) of the back-barrier HEMT are 172 GHz and 217 GHz, respectively, which are higher than those of the conventional HEMT with the same gate length.

The proton implantation is one of key procedures to confine the current diffusion in vertical cavity surface emitting lasers (VCSELs), in which the proton implanted depth and profile are main parameters. Threshold characteristics of VCSELs with various proton implanted depths are studied after optical, electrical and thermal fields have been simulated self-consistently in three dimensions. It is found that for VCSELs with confinement radius of 2 μm, increasing proton implanted depth can reduce the injected current threshold power and enhance the laser temperature in active region. Numerical results also indicate that there are optimal values for current aperture in proton implanted VCSELs. The minimum injected current threshold can be achieved in VCSELs with proton implantation near the active region and confinement radius of 1.5 μm, while the VCSELs with proton implantation in the middle of p-type distributed Bragg reflectors (DBRs) and confinement radius of 2.5 μm can realize the minimum temperature.

Background There is uncertainty surrounding the differences in outcomes after intracerebral haemorrhage (ICH) between men and women. This study aimed to investigate the sex differences in clinical characteristics, severity and outcomes of Chinese ICH patients. Methods The Nanjing First Hospital stroke registry was a hospital-based registry of stroke patients with 1-year prospective follow-up. From 2004 to 2008, a total of 651 consecutively recruited patients with acute ICH were enrolled. Primary outcome was death or dependency defined as a modified Rankin Scale score of 3–6 at 12 months. Multivariable logistic regression analyses were performed to determine whether there were sex differences in clinical outcomes after ICH. Clinically important and biologically plausible risk factors of death or dependency were selected from available variables. Results A total of 615 ICH patients were enrolled. There was no significant difference in age (63.5 ± 14.0 vs. 62.7 ± 12.7, p = 0.500) between women and men. At baseline, men were more likely to be current smokers (46.1% vs. 3.6%, P < 0.001) or current drinkers (35.4% vs. 3.6%, P < 0.001), but women had higher admission National Institute of Health Stroke Scale (NIHSS) scores than men (10 vs. 8, P = 0.039). Women also had higher rates of death or dependency at 3, 6, and 12 months (61.2% vs. 46.8%, P = 0.001; 56.7% vs. 45.3%, P = 0.009; and 51.8% vs. 44.1%, P = 0.065; respectively). After adjustment for age, existing hypertension and diabetes, prior stroke, previous ischemic heart disease, previous atrial fibrillation, current smoking and alcohol consumption status, pre-stroke dependency, onset-to-door time, admission NIHSS score, admission systolic blood pressure and location of bleeding, the association between the female gender and death or dependency remained statistical significant at 3 months [odds ratio (OR): 1.76; 95% confidence interval (CI): 1.07-2.89], but did not reach statistical significance at 6 months (OR: 1.59; 95% CI: 0.99-2.54) and 12 months (OR: 1.22; 95% CI: 0.77-1.95). Conclusions In a Chinese population, women are more likely to be dead or dependent early after ICH than men. However, this gender difference gradually attenuates over the period of 12 months.

The chromaticity diagram is also needed in the instrument of a non-contact system for measuring color of printed material. The purpose of this paper is to design the color chromaticity diagram identical with the CIE 1931 and its program in MATLAB with digital image processing is realized. The chromaticity diagram in a binary format representation as black and white is used and the boundary for every color is confined by a closed black real line. More than 20 kinds of colors are selected by the psychophysiology of vision according to the CIE 1931 and their values in RGB are also are given. After every region colors are put in, the closed black real lines are wiped away and their values of RGB are updated according to the value for the nearest color region. The program including the filters in RGB space run until the all steps between every two colors up to the psychophysiology of vision, the chromaticity diagram is obtained. The values of RGB in every position in the chromaticity diagram can be presented.

Recently published data indicate that CYP2C19*2 allele is the major determinant of metabolic bioactivation of clopidogrel and thereby variability of antiplatelet effect of clopidogrel in white or black patients undergoing elective coronary stent placement. The conclusion may not be fully generalized or extrapolated to the Chinese people due to significantly higher frequencies of the CYP2C19*2 or *3 variant alleles. We sought to investigate whether the CYP2C19*2 or *3 alleles affects platelet reactivity of clopidogrel in Chinese stroke patients. The study included 183 consecutive Chinese stroke patients after loading with clopidogrel 300 mg. Platelet function was assessed by adenosine diphosphate-induced (ADP 20 micromol/L) platelet aggregation and by light transmittance aggregometry (LTA) after seven 75-mg maintenance doses of clopidogrel before discharge. CYP2C19*2 or *3 genotypes were determined by time-of-flight mass spectrometer (MALDI/TOF-MS). In those patients who were carriers of 1 mutant allele (mutant heterozygotes, CYP2C19*1/*2 or *1/*3), ADP-induced maximum platelet aggregation (MPA) were significantly different compared with wild-type homozygous patients [37.2% (IQR, 19.6 to 50.5%) versus 23.6% (IQR, 14.0 to 35.4%), respectively; P=0.002]. In addition, in the patients who were carriers of 2 mutant allele (mutant homozygotes, CYP2C19*2/*2, *2/*3 or *3/*3,), MPA were also significantly different compared with wildtype homozygous patients [35.7% (IQR, 21.0 to 78.1%) versus 23.6% (IQR, 14.0 to 35.4%, respectively; P = 0.039]. By multivariable linear regression, CYP2C19*2 or *3 loss-of-function alleles were independently associated with ADP-induced MPA measurements (partial R2 = 0.138, P = 0.001). CYP2C19*2 or *3 allele does link to increased MPA and clopidogrel response.

For gaining effective features to realize fault diagnosis in the LED illuminating circuits, a method of fault diagnosis in analog circuits based on cloud model is proposed. In this paper, the analog circuit with a sinusoidal input is simulated and its output is sampled to extract sequences of each layer of wavelet coefficients as the initial fault feature vectors. Then, the backward cloud algorithm of cloud model is applied to obtain corresponding digital features of the wavelet coefficients, which include the Expected value E x , the Entropy E n and the Hyper entropy H e as new fault feature vectors, named fault cloud feature vectors. Finally, Fault cloud feature vectors are used to BP neural networks to classify fault and realize the fault diagnosis in analog circuits. The simulation result on the LED illuminating circuits shows that this method is feasible and has many powerful virtues, such as diagnosing and locating faults quickly and exactly.

This paper presents a simulation analysis for the threshold characteristics of proton implanted vertical-cavity surfaceemitting lasers(VCSELs) with the aid of optical-electrical-thermal-gain model. The equations for potential, the carrier density, optical transverse mode and thermal field are given. The distributions of injected current, the fundamental transverse mode, carrier and temperature for VCSELs at various aperture radii of 1,2,4 and 6 microns are studied selfconsistently. The threshold injected currents versus the current aperture radii are obtained. The calculated results show that decreasing aperture sizes is an effective method to drop the threshold currents only when the current radii are larger than 2 micron. On the other hand, the threshold currents with the decrease of aperture radii for too small sizes of current aperture. The current aperture radius for low threshold proton implanted VCSEL is found. The threshold currents may drop with improving the confinement of current, while too much small current apertures also damage the threshold. The reason that few VCSEL with smaller aperture radii realize to operate is explained.

The generation of high-power green laser is important for the numerous applications in industry, medicine, research and even entertainment. In addition, mode-locked lasers operating at ~100 MHz repetition rate, are particularly attractive for nonlinear optics and spectroscopy. Characteristics of high-power, mode-locking green radiation obtained by Nd:YVO 4 at 1064nm in the nonlinear crystals of PPKTP are studied. Two identical highly efficient diode-pumped laser heads placed in a plane-plane resonator are used for the input laser based on theoretically investigation of the thermally stable region of Nd:YVO 4 rod. The PPKTP crystal of Brewster-cut is used in the external cavity configuration, the cavity losses is significantly smaller than for an antireflection(AR) coated crystal cut for normal incident, however, the effective nonlinearity is reduction. Frequency doubling nonlinear mirror(FDNLM) based on intensity dependent reflection in the laser cavity is used for the laser mode-locking. A stable green output power of 510W with pulse repetition rate of 100MHz and net conversion efficiency of η=50% at an input mode-matched power of 2KW are obtained. Meanwhile, thermal effects in the nonlinear crystal severely limit the efficiency of the laser configuration when using high pump power.

The full-width half maximum (FWHM) is one of important parameters that can exhibit the micro-cavity effect. An approximate analytic expression of spontaneous emission for GaAs micro-cavity in our previous work can be instead of the numerical integral, but it is so complex that it cannot give the analytic expression of FWHM. This paper will set up another approximation to give a new analytic expression of spontaneous emission, which can give the same results with the numerical integral in the vertical direction, in which Fermi-Dirac distribution functions of electrons in the conduction band and the valence band are considered. Although the new approximate analytic expression is simpler than that in our previous work, it can be used to study the spontaneous emission spectra FWHM with a small angle in the vertical direction of planar micro-cavity. The two approximate expressions of FWHM for enhancement spontaneous emission spectrum into the small angle are obtained by the new analytic expression of spontaneous emission, in which the triangular function relation and the first order series of sine and cosine are used respectively. The curves for the FHWM versus the reflectivity by the two expressions of FWHM in the GaAs micro-cavity are also compared.

To study the effects of noninvasive positive pressure ventilation (NPPV) on respiratory muscle fatigue in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD).Thirty-two COPD patients were randomly assigned to group I (conventional therapy + NPPV) and group II (conventional therapy alone). Sixteen normal volunteers served as the healthy control group (normal lung function). Scale for accessory muscle use, dyspnea score, lung function, arterial blood gases, P(0.1) and phrenic nerve conduction were measured before and after the treatment.Before treatment, dyspnea and accessory muscle use were present in group I and group II. P(0.1) in the two groups was higher than that in the normal volunteers. Phrenic nerve conduction latency showed no significant difference among the three groups, but the diaphragmatic compound muscle action potential in group I and group II were lower than that in the normal volunteers (P0.01). On the 8th day of treatment, symptoms improved in both group I and group II. PaCO2 showed a decreased of (31.0 +/- 17.6) mm Hg in group I, the difference being significant compared to group II (P0.05). All the parameters of lung function improved in group I, but only forced expired volume in one second (FEV1) increased in group II. Compared with group II, the P(0.1), in group I decreased significantly [(2.8 +/- 1.0) cm H2O vs (0.3 +/- 0.5) cm H2O, P0.01] , and the diaphragmatic compound muscle action potential increased significantly after treatment [left: (188 +/- 62) microV vs (138 +/- 50) microV, P0.05; right: (200 +/- 52) microV vs (150 +/- 52) microV, P0.01].Respiratory muscle fatigue was evident in patients with acute exacerbations of COPD. NPPV led to a more rapid improvement in gas exchange and respiratory muscle fatigue.

Polycrystalline Bi 0.975 La 0.025 Fe 0.975 Ni 0.025 O 3 (BLFNO) film is fabricated on Pt / Ti / SiO 2/ Si (111) substrate by sol–gel method. It is found that the well-crystallized BLFNO film is polycrystalline, and the Pt / BLFNO / Pt capacitor possesses good ferroelectric properties with remnant polarization of 74 μC/cm2 at electric field of 833 kV/cm. Moreover, it is also found that the leakage current density of the Pt / BLFNO / Pt capacitor increases with the increase of measurement temperature ranging from 100 to 300 K. The leakage density of the Pt / BLFNO / Pt capacitor satisfies space-charge-limited conduction (SCLC) at higher electric field and shows little dependence on voltage polarity and temperature, but shows polarity and temperature dependence at lower applied electric field. With temperature increasing from 100 to 300 K at lower applied electric field, the most likely conduction mechanism is from Ohmic behavior to SCLC for positive biases, but no clear dominant mechanism for negative biases is shown.

Polycrystalline Bi0.975La0.025Fe0.975Ni0.025O3 (BLFNO) film is fabricated on Pt/Ti/SiO2/Si(111) substrate by sol–gel method. It is found that the well-crystallized BLFNO film is polycrystalline, and the Pt/BLFNO/Pt capacitor possesses good ferroelectric properties with remnant polarization of 74 μC/cm2 at electric field of 833 kV/cm. Moreover, it is also found that the leakage current density of the Pt/BLFNO/Pt capacitor increases with the increase of measurement temperature ranging from 100 to 300 K. The leakage density of the Pt/BLFNO/Pt capacitor satisfies space-charge-limited conduction (SCLC) at higher electric field and shows little dependence on voltage polarity and temperature, but shows polarity and temperature dependence at lower applied electric field. With temperature increasing from 100 to 300 K at lower applied electric field, the most likely conduction mechanism is from Ohmic behavior to SCLC for positive biases, but no clear dominant mechanism for negative biases is shown.