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Traditional belief revision usually considers generic logic formulas, whilst in practical applications some formulas might even be inappropriate for beliefs. For instance, the formula
$p \wedge q$
is syntactically consistent and is also an acceptable belief when there are no restrictions, but it might become unacceptable under restrictions in some context. If we assume that p represents ‘manufacturing product A’ and q represents ‘manufacturing product B’, an example of such a context would be the knowledge that there are not enough resources to manufacture them both and, hence,
$p \wedge q$
would not be an acceptable belief. In this article, we propose a generic framework for belief revision under restrictions. We consider restrictions of either fixed or dynamic nature, and devise several postulates to characterize the behaviour of changing beliefs when new evidence emerges or the restriction changes. Moreover, we show that there is a representation theorem for each type of restriction. Finally, we discuss belief revision of qualitative spatio-temporal information under restrictions as an application of this new framework.
The mumps resurgence has frequently been reported around the world in recent years, especially in many counties mumps vaccines have been widely used. This study aimed to describe the spatial epidemiological characteristics of mumps in Jiangsu, and provide a scientific basis for the implementation and adjustment of strategies to prevent and control mumps. The epidemiological characteristics were described with ratio or proportion. Spatial autocorrelation, Tango's flexible spatial scan statistics, and Kulldorff's elliptic spatiotemporal scan statistics were applied to identify the spatial autocorrelation, detect hot and cold spots of mumps incidence, and aggregation areas. A total of 172 775 cases were reported from 2004 to 2020 in Jiangsu. The general trend of mumps incidence is declining with a bimodal seasonal distribution identified mainly in summer and winter, respectively. Children aged 5–10 years old are the main risk group. A migration trend of hot spots from southeast to northwest over time was found. Similar high-risk aggregations were detected in the northwestern parts through spatial-temporal analysis with the most likely cluster time frame around 2019. Local medical and health administrations should formulate and implement targeted health care policies and allocate health resources more appropriately corresponding to the epidemiological characteristics of mumps.
In this paper, we innovatively conduct a Porro prism-based beam pointing stability promotion technique research and realize a high-performance rod-type photonic crystal fiber-based chirped pulse amplification (CPA) system, mainly including a frequency-reduced all-fiber pre-amplification stage, photonic crystal rod-based main amplification stage, and 1600 lines/mm transmission grating-pair compressor. Laser output with average power of 50 W, repetition rates of 500 kHz, pulse energy of 100 μJ, pulse duration of 830 fs, beam quality of M2<1.3, power fluctuation of 0.55% root mean square, and beam pointing drift of 19 μrad/°C over 8 h is realized. The high-performance laser system has an enormous application potential in fundamental research and precision manufacturing fields.
Parabronema skrjabini is one of the most harmful nematodes to camels and is responsible for economic losses in animal husbandry industry. There is an urgent need for in-depth studies of potential vectors of the nematode due to its scant regarding information. As previous studies indicated that flies may be the vectors of P. skrjabini, we captured flies in the main camel-producing areas of Inner Mongolia. After autopsy of the specimens of two species of horn flies, we observed the morphology of the suspected nematode larvae found in them. Internal transcribed spacer ribosomal-DNA gene sequences were considered the best candidate to confirm the species of the larvae found. Our results showed that the homology compared with P. skrjabini was 99.5% in GenBank. Subsequently, we preliminarily identified two species of horn flies through morphological observation and then sequenced the mitochondrial-DNA-gene cytochrome oxidase subunit I obtained from two species of horn flies, with 100 and 99.2% similarity to sequences deposited in GenBank, respectively. Thus, we identified Haematobia titillans and Haematobia irritans and provided evidence for their potential role as vectors of parabronemosis. Our study provides reference for future research on the life history of the nematode and the vectors of parabronemosis.
To explore whether different polyvinylpyrrolidone (PVP) concentrations affect the results of intracytoplasmic sperm injection (ICSI), a prospective study was conducted for 194 couples undergoing 210 ICSI therapy cycles. These cycles were divided into three groups (10, 7 and 5% groups) using the corresponding concentration of PVP for sperm immobilization. The main outcome measures were analyzed. Results indicated that, with a decrease in PVP concentrations, all of the main outcome measures increased. In particular, the high-quality cleavage embryo rate in the 7% group was significantly lower than in the 5% group (P < 0.01), and the cleavage, high-quality cleavage embryo, and high-quality blastocyst rates in the 5% group were significantly higher than those in the 10% group (all P < 0.001). For high-/intermediate-quality semen, all of the main outcome measures were significantly increased with 5% PVP. For the poor-quality semen, only the high-quality cleavage embryo and high-quality blastocyst rates were significantly higher in the 5% group. Therefore, lowering PVP concentrations greatly promoted the development of embryos in ICSI cycles, with an optimal concentration of 5% for ICSI.
Remote sensing data, including those from Landsat Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM +), the Shuttle Radar Topography Mission Digital Elevation Model (SRTM4.1 DEM), and the Geoscience Laser Altimeter System Ice, Cloud, and Land Elevation Satellite (Glas/ICESat), show that from 1991 to 2013 the glacier area in the Depuchangdake region of northwestern Tibet decreased from 409 to 393 km2, an overall loss of 16 km2, or 3.9% of the entire 1991 glacial area. The mean glacier-thinning rate was − 0.40 ± 0.16 m equivalent height of water per year (w.e./yr), equating to a glacier mass balance of − 0.16 ± 0.07 km3 w.e./yr. Total mass loss from 2003 to 2009 was − 1.13 ± 0.46 km3. Glacier retreat likely reflects increases in annual total radiation, annual positive degree days, and maximum temperature, with concurrent increases in precipitation insufficient to replenish glacial mass loss. The rate of glacier retreat in Depuchangdake is less than that for Himalayan glaciers in Indian monsoon-dominated areas, but greater than that for Karakoram glaciers in mid-latitude westerly-dominated areas. Glacier type, climate zone, and climate change all impact on the differing degrees of long-term regional glacial change rate; however, special glacier distribution forms can sometimes lead to exceptional circumstances.
Intracytoplasmic sperm injection (ICSI) has been widely applied in humans, mice, and some domestic animals to cure human infertility, or produce genetically superior or genetically engineered animals. However, the production efficiency of ICSI in pigs remains quite low. In this study, we developed a new sperm pretreatment method to improve production efficiency of ICSI in pigs. Experiment 1 revealed that pretreating porcine sperm with 2.5 mg/ml lipase before ICSI operation, not only can reduce the adhesion between sperm and the injection pipette without adding polyvinylpyrrolidone (PVP) in the operating medium, but also significantly improve male pronuclei (MPN) formation rate (55.56% vs. 40.00% (0 mg/ml), 42.59% (5.0 mg/ml), 40.00% (10.0 mg/ml), P < 0.05) and enhance developmental competence of ICSI embryos (26.03% vs. 10.87% (0 mg/ml), 10.00% (5.0 mg/ml), 10.13% (10.0 mg/ml), P < 0.05). Experiment 2 showed that this method has a higher MPN formation rate (50.47% vs. 30.78%, P < 0.05) and blastocyst rate (18.81% vs. 7.41%, P < 0.05) than the PVP method, and was better than the Triton X-100 treatment method (50.47% vs. 46.23%, 18.81% vs. 12.75%). Therefore, pretreating porcine sperm with 2.5 mg/ml lipase before ICSI operation is highly recommended, instead of adding PVP in the operating medium.
The coordinate transformation offers a remarkable way to design cloaks that can steer electromagnetic fields so as to prevent waves from penetrating into the cloaked region (denoted by Ω0, where the objects inside are invisible to observers outside). The ideal circular and elliptic cylindrical cloaked regions are blown up from a point and a line segment, respectively so the transformed material parameters and the corresponding coefficients of the resulted equations are highly singular at the cloaking boundary ∂Ω0. The electric field or magnetic field is not continuous across ∂Ω0. The imposition of appropriate cloaking boundary conditions (CBCs) to achieve perfect concealment is a crucial but challenging issue.
Based upon the principle that a well-behaved electromagnetic field in the original space must be well-behaved in the transformed space as well, we obtain CBCs that intrinsically relate to the essential “pole” conditions of a singular transformation. We also find that for the elliptic cylindrical cloak, the CBCs should be imposed differently for the cosine-elliptic and sine-elliptic components of the decomposed fields. With these at our disposal, we can rigorously show that the governing equation in Ω0 can be decoupled from the exterior region , and the total fields in the cloaked region vanish under mild conditions. We emphasize that our proposal of CBCs is different from any existing ones.
Using the exact circular (resp., elliptic) Dirichlet-to-Neumann (DtN) non-reflecting boundary conditions to reduce the unbounded domain to a bounded domain, we introduce an accurate and efficient Fourier-Legendre spectral-element method (FLSEM) (resp., Mathieu-Legendre spectral-element method (MLSEM)) to simulate the circular cylindrical cloak (resp., elliptic cylindrical cloak). We provide ample numerical results to demonstrate that the perfect concealment of waves can be achieved for the ideal circular/elliptic cylindrical cloaks under our proposed CBCs and accurate numerical solvers.
Early identification of patients with bipolar disorder during their first depressive episode is beneficial to the outcome of the disorder and treatment, but traditionally this has been a great challenge to clinicians. Recently, brain-derived neurotrophic factor (BDNF) has been suggested to be involved in the pathophysiology of bipolar disorder and major depressive disorder (MDD), but it is not clear whether BDNF levels can be used to predict bipolar disorder among patients in their first major depressive episode.
To explore whether BDNF levels can differentiate between MDD and bipolar disorder in the first depressive episode.
A total of 203 patients with a first major depressive episode as well as 167 healthy controls were recruited. After 3 years of bi-annual follow-up, 164 patients with a major depressive episode completed the study, and of these, 21 were identified as having bipolar disorder and 143 patients were diagnosed as having MDD. BDNF gene expression and plasma levels at baseline were compared among the bipolar disorder, MDD and healthy control groups. Logistic regression and decision tree methods were applied to determine the best model for predicting bipolar disorder at the first depressive episode.
At baseline, patients in the bipolar disorder and MDD groups showed lower BDNF mRNA levels (P<0.001 and P = 0.02 respectively) and plasma levels (P = 0.002 and P = 0.01 respectively) compared with healthy controls. Similarly, BDNF levels in the bipolar disorder group were lower than those in the MDD group. These results showed that the best model for predicting bipolar disorder during a first depressive episode was a combination of BDNF mRNA levels with plasma BDNF levels (receiver operating characteristics (ROC) = 0.80, logistic regression; ROC = 0.84, decision tree).
Our findings suggest that BDNF levels may serve as a potential differential diagnostic biomarker for bipolar disorder in a patient's first depressive episode.
Common psychiatric disorders are highly heritable, indicating that genetic factors play an important role in their aetiology. The CACNA1C gene, which codes for subunit alpha-1C of the Cav1.2 voltage-dependent L-type calcium channel, has been consistently found to be the shared risk gene for several kinds of mental disorder.
To investigate whether CACNA1C is a susceptibility gene for schizophrenia and major depressive disorder in the Han Chinese population.
We carried out a case–control study of 1235 patients with schizophrenia, 1045 with major depressive disorder and 1235 healthy controls. A tag single nucleotide polymorphism (SNP) rs1006737 along with another 10 tag SNPs in the CACNA1C gene were genotyped in all samples.
We found that rs1006737 was associated with both schizophrenia (Pallele = 0.0014, Pgenotype = 0.006, odds ratio (OR) = 1.384, 95% CI 1.134–1.690) and major depressive disorder (Pallele = 0.0007, Pgenotype = 0.003, OR = 1.425, 95% CI 1.160–1.752).
Our findings support CACNA1C being a risk gene for both schizophrenia and major depressive disorder in the Han Chinese population.
Experimental studies have suggested that tea consumption could lower the risk of dyslipidaemia. However, epidemiological evidence is limited, especially in southern China, where oolong tea is the most widely consumed beverage. We conducted a population-based case–control study to evaluate the association between consumption of tea, especially oolong tea, and risk of dyslipidaemia in Shantou, southern China, from 2010 to 2011. Information on tea consumption, lifestyle characteristics and food consumption frequency of 1651 patients with newly diagnosed dyslipidaemia and 1390 controls was obtained using a semi-quantitative questionnaire. Anthropometric variables and serum biochemical indices were determined. Drinking more than 600 ml (2 paos) of green, oolong or black tea daily was found to be associated with the lowest odds of dyslipidaemia risk (P< 0·001) when compared with non-consumption, but only oolong tea consumption was found to be associated with low HDL-cholesterol levels. A dose–response relationship between duration of tea consumption and risk of dyslipidaemia (OR 0·10, 95 % CI 0·06, 0·16), as well as that between amount of dried tea leaves brewed and risk of dyslipidaemia (OR 0·34, 95 % CI 0·24, 0·48), was found. Moreover, consumption of oolong tea for the longest duration was found to be associated with 3·22, 11·99 and 6·69 % lower blood total cholesterol, TAG and LDL-cholesterol levels, respectively. In conclusion, the present study indicates that long-term oolong tea consumption may be associated with a lower risk of dyslipidaemia in the population of Shantou in southern China.
The multilayered films-based charge trap flash memory cells were fabricated by incorporating high-k ZrO2/Al2O3 nanolaminates as charge trapping layer and amorphous Al2O3 as tunneling and blocking layers. The thickness of high-k ZrO2 or Al2O3 film in charge trapping layer after annealing treatment was about 1.5 nm for each layer. The charge storage characteristics of such memory cells were measured, and the results demonstrated that they had a large hysteresis memory window of 3.85 V at a sweeping gate voltage of ±8 V, an excellent endurance up to 105 write/erase cycles and a small charge loss of 9.6% after 10 years.
In shipborne Transfer Alignment (TA) applications, partial observability is one of the most important factors limiting convergence velocity. This paper proposes a new method of attributing weak observable states and lever-arm variables to a group of constraints in order to improve the observability of TA model. This yields the so-called Constrained Transfer Alignment (CTA) model which is uniformly observable even under zero-manoeuvre conditions. Within this framework, the Moving Horizon Estimation (MHE) and its stability analysis are also addressed. Finally, comparative simulation results are given to demonstrate the advantages of the proposed approach.
The roles of hydrogen plasma radicals on passivation of several kinds of crystallized poly-Si thin films were investigated using optical emission spectroscopy (OES) combined with Hall mobility, Raman spectra, and absorption coefficient spectra. It was found that different kinds of hydrogen plasma radicals are responsible for passivation of dissimilar poly-Si crystallized by different method. Radicals Hα with lower energy are mainly responsible for passivating the poly-Si crystallized by solid phase crystallization (SPC) whose crystallization precursor was made by plasma enhanced chemical vapor deposition (PECVD). Higher energy radicals H* are more effective in passivating defects left over by Ni in poly-Si crystallized by Metal Induced Crystallization (MIC). The highest energy radicals Hβ and Hγ are needed to passivate the defects in poly-Si crystallized by SPC but whose precursor was made by low pressure CVD (LPCVD).
A technique to improve and accelerate aluminum induced crystallization (AIC) by hydrogen plasma is proposed in this paper. Raman spectroscopy and Secondary Ion Mass Spectrometry of crystallized poly-Si thin films show that hydrogen plasma radicals reduce the crystallization time of AIC. This technique shortens the annealing time from 10 hours to 4 hours and increases the Hall mobility from 22.1 cm2/V·s to 42.5 cm2/V·s. The possible mechanism of AIC assisted by hydrogen radicals will also be discussed.
The influence of the density of gap states and the band gap width of the intrinsic a-Si:H active layer on the characteristics of a-Si PIN/OLED coupling pair was analyzed by a-Si:H PIN/OLED CAD simulation model. The CAD simulation model was carried out based on a-Si PIN Hack & Shur model and OLED TCL transport model. At the same band gap width, for the intrinsic a-Si:H active layer with the higher density of gap states, the reverse current of a-Si PIN trended to be saturated at the higher reverse bias voltage. As a result, I-V curve of a-Si PIN/OLED around the turn point Vt became smoother with the increase of the density of gap states. At the same state density, the light induced current of a-Si PIN increased against the band gap width, assuming the input light had the same spectrum as AM1.5 solar light. Thus the luminance emitted from OLED increased with the decrease of the band gap width because OLED belongs to the light-emitting device controlled by current. The simulation results also showed that the influence of the state density intensified with the increase of the band gap of a-Si:H.
Thin films of lanthanum substituted bismuth titanate, Bi4−xLaxTi3O12 (BLTx), were prepared by chemical solution deposition. Crystallized BLTx films were obtained by rapid thermal annealing at a temperature as low as 650 °C. Structural and electrical characteristics of crystalline BLTx films were studied as functions of La composition. Structure characterization was conducted by x-ray diffraction and Raman spectroscopy. The lowest lattice vibration mode around 116 cm−1 showed softening with increasing lanthanum composition. Surface morphology of BLTx films were recorded by scanning electron microscopy. BLTx films have saturated hysteresis loops with remnant polarization of 9.7, 12.3, and 4.5 μC/cm2, respectively, for x = 0.50, 0.75, and 1.00 films. BLT0.75 films showed fatigue-free behavior over 250 kV/cm, 50 kHz cycling, which could be compared with that of SrBi2Ta2O9 thin films. Fatigue resistance decrease at lower cycling field. The field dependence of fatigue property was discussed briefly in terms of competition between domain pinning and field-assisted unpinning.
The patterned nc-Si/a-SiNx:H superlattices were fabricated by using laser interference crystallization method and investigated with atomic force microscope (AFM), micro-Raman spectroscope, cross-section transmission electron microscope (TEM) and high resolution electron microscope (HREM). We found that after laser irradiation, self-assembled Si nanocrystallites (nc-Si) are formed within the initial a-Si:H sublayers, moreover, in the plane parallel to the surface of the films, these nc-Si orderly distribute in the certain regions with the same periodicity of 2.0 µm as phase shifting mask grating. Based on the structural analyses, the crystallization mechanism and the origin of the self-assembled phenomena are briefly discussed.
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