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Coal dust explosion is of great importance for both theoretical analysis and practical applications. However, there is not a complete theory to reveal its mechanism. Here we show that the ignition energy plays an important role. An experiment is designed using different volatile coal dusts under different ignition energies, and the results are extremely helpful for avoiding coal dust explosion and can be also used for verification of a new theory.

Quantum entanglement and correlations in the spin-1 Heisenberg chain with single-ion anisotropy are investigated using the quantum renormalization group method. Negativity and quantum discord (QD) are calculated with various anisotropy parameters $\bigtriangleup$ and single-ion anisotropy parameters $D$. We focus on the relations between two abovementioned physical quantities and on transitions between the N\'eel, Haldane, and Large-D phases. It is found that both negativity and QD exhibit step-like patterns in different phases as the size of the system increases. Interestingly, the single-ion anisotropy parameter $D$, which can be modulated using nuclear electric resonance (2020 \textit{Nature} \textbf{579} 205), plays an important role in tuning the quantum phase transition (QPT) of the system. Both the first partial derivative of the negativity and quantum discord with respect to $D$ or $\bigtriangleup$ exhibit nonanalytic behavior at the phase transition points, which corresponds directly to the divergence of the correlation length. The quantum correlation critical exponents derived from negativity and QD are equal, and are the reciprocal of the correlation length exponent at each critical point. This work extends the application of quantum entanglement and correlations as tools for depicting QPTs in spin-1 systems., Comment: 28 pages, 17 figures

Employing the correlation matrix technique, the spatial distribution of thermal energy in two-dimensional triangular lattices in equilibrium, interacting with linear springs, is studied. It is found that the spatial distribution of thermal energy varies with the included angle of the springs. In addition, the average thermal energy of the longer springs is lower. Springs with different included angle and length will lead to an inhomogeneous spatial distribution of thermal energy. This suggests that the spatial distribution of thermal energy is affected by the geometrical structure of the system: the more asymmetric the geometrical structure of the system is, the more inhomogeneous is the spatial distribution of thermal energy.

The dynamics of the random Ising spin chain in coexisting transverse and longitudinal magnetic fields is studied by the recursion method. Both the spin autocorrelation function and its spectral density are investigated by numerical calculations. It is found that system’s dynamical behaviors depend on the deviation σ J of the random exchange coupling between nearest-neighbor spins and the ratio r l t of the longitudinal and the transverse fields: (i) For r l t = 0 , the system undergoes two crossovers from N independent spins precessing about the transverse magnetic field to a collective-mode behavior, and then to a central-peak behavior as σ J increases. (ii) For r l t ≠ 0 , the system may exhibit a coexistence behavior of a collective-mode one and a central-peak one. When σ J is small (or large enough), system undergoes a crossover from a coexistence behavior (or a disordered behavior) to a central-peak behavior as r l t increases. (iii) Increasing σ J depresses effects of both the transverse and the longitudinal magnetic fields. (iv) Quantum random Ising chain in coexisting magnetic fields may exhibit under-damping and critical-damping characteristics simultaneously. These results indicate that changing the external magnetic fields may control and manipulate the dynamics of the random Ising chain.

OBJECTIVE: To determine the high-risk factors for early failure of high-flow nasal cannula (HFNC) oxygen therapy in children with acute respiratory insufficiency (ARI). METHODS: The clinical data of 123 children with ARI were reviewed who received HFNC oxygen therapy in the pediatric intensive care unit from January to June, 2018. The children who did not require an upgrade of respiratory support during hospitalization and were successfully weaned from HFNC were classified as HFNC success group (69 cases). Of the remaining children (54 cases) who required an upgrade of their respiratory support during hospitalization, those that needed to upgrade their respiratory support within 48 hours of receiving HFNC were classified as early HFNC failure group (46 cases). Risk factors for early failure of HFNC were determined using multivariate logistic regression analysis. RESULTS: The incidence rates of shock, sepsis, intracranial hypertension syndrome, and multiple organ dysfunction syndrome were significantly higher in the early HFNC failure group than in the HFNC success group (P < 0.05). Before implementation of respiratory support, the early HFNC failure group had significantly lower Glasgow coma score, pH value, and oxygenation index and significantly higher Pediatric Risk of Mortality (PRISM) score and PaCO(2)/PaO(2) ratio than the HFNC success group (P < 0.05). Multivariate logistic regression analysis showed that PRISM score > 4.5 and PaCO(2)/PaO(2) ratio > 0.64 were independent risk factors for early HFNC failure (OR=5.535 and 9.089 respectively; P < 0.05). CONCLUSIONS: Pediatric ARI patients with PRISM score > 4.5 or PaCO(2)/PaO(2) ratio > 0.64 have relatively high risk of early HFNC failure.

ObjectiveTo describe the epidemiology of holoprosencephaly (HPE) in China with special reference to prevalence and associated anomalies.MethodsData were abstracted from the Chinese Birth Defects Monitoring Network for the period 2007-2014. Birth prevalence of HPE were assessed by birth year, fetal/infant sex, maternal age, and maternal residential area. Poisson regressions were used to calculate the crude and adjusted prevalence ratios (PR) and their 95% confidence intervals, and linear chi-square test was used to explore time trend for the prevalence of HPE.ResultsA total of 1222 HPE cases were identified in 13,284,142 births, yielding an overall prevalence of 0.92 per 10,000 births. The annual prevalence of HPE presented an upward trend (PConclusionsHPE is an important perinatal health issue because of its poor prognosis. This is the first study depicting a picture of epidemiological characteristics of HPE in China, which can provide useful references for future studies.

The quantum entanglement and quantum phase transition of the transverse-field Ising model on a two-dimensional square lattice were investigated by applying the quantum renormalization group method. The quantum critical point (QCP) and the correlation length exponent, ν , were obtained. By taking the concurrence as a measure of entanglement, the entanglement between spin blocks near the QCP is calculated as the size of the system becomes large. The entanglement reaches a maximum close to QCP, and can exist in a small range around QCP just at the limit of thermodynamics. The nonanalytic behavior of the derivative of the entanglement with the external field shows that the system undergoes a second order quantum phase transition from a ferromagnetic phase to a paramagnetic phase. The finite-size scaling behavior of the entanglement is described, and the relationship between the entanglement exponent, θ , the correlation length exponent, ν , and the dimension of the system d is also found, i.e., θ = 1 / ( ν d ) .

Quantum phase transitions (QPT) in the infinite-long Ising-XXZ diamond chain, characterized by the quantum correlations measured by the quantum discord (QD) and the entanglement of formation (EoF), are investigated exactly by the transfer-matrix method. QD and EoF are calculated numerically for different values of anisotropy parameter, external magnetic field, and temperature. It is found that the singularity of QD and EoF around quantum critical points (QCPs), especially that of their first derivatives may not only spotlight the QCPs but also depict the QPT from unentangled state in ferrimagnetic phase to an entangled state in frustrated phase or to an entangled state in the ferrimagnetic phase.

Adopting concurrence as entanglement measure, we study entanglement and quantum phase transition of the Ising spin systems on the triangular lattice and Sierpi\ifmmode \acute{n}\else \'{n}\fi{}ski fractal lattices by using the quantum renormalization-group method. It is found that the ground-state entanglement between two spins (or spin blocks) depends on the following factors: the size of system, the magnetic field, the exchange coupling, and the structure of lattice. As the size of the system becomes large, (a) the range of the magnetic field, in which the entanglement exists, contracts gradually and focuses on the critical point; and (b) the first derivative of entanglement shows singular behavior, and its maximum or minimum is approaching to the critical point gradually. The scaling behaviors of entanglement on the different lattices are similar but the scaling relations are diverse. For the triangular lattice, the space dimensionality determines the scaling relationship between the critical exponent of the entanglement and the critical exponent correlation length. However, for fractal lattices, it is the fractal dimensionality but not the space one to determine this relationship.

The aim of the present study was to elucidate the effects of blocking the calcium signaling pathway of astrocytes (ASs) on oxygen and glucose deprivation (OGD)‑induced AS injury. The association between the changes in the concentrations of AS‑derived transmitter ATP and glutamic acid, and the changes in calcium signaling under the challenge of OGD were investigated. The cortical ASs of Sprague Dawley rats were cultured to establish the OGD models of ASs. The extracellular concentrations of ATP and glutamic acid in the normal group and the OGD group were detected, and the intracellular concentration of calcium ions (Ca2+) was detected. The effects of 2'‑deoxy‑N6‑methyl adenosine 3', 5'‑diphosphate diammonium salt (MRS2179), a P2Y1 receptor antagonist, on the release of calcium and glutamic acid of ASs under the condition of OGD were observed. The OGD challenge induced the release of glutamic acid and ATP by ASs in a time‑dependent manner, whereas elevation in the concentration of glutamic acid lagged behind that of the ATP and Ca2+. The concentration of Ca2+ inside ASs peaked 16 h after OGD, following which the concentration of Ca2+ was decreased. The effects of elevated release of glutamic acid by ASs when challenged by OGD may be blocked by MRS2179, a P2Y1 receptor antagonist. Furthermore, MRS2179 may significantly mitigate OGD‑induced AS injury and increase cell survival. The ASs of rats cultured in vitro expressed P2Y1 receptors, which may inhibit excessive elevation in the concentration of intracellular Ca2+. Avoidance of intracellular calcium overload and the excessive release of glutamic acid may be an important reason why MRS2179 mitigates OGD‑induced AS injury.

The geometrically frustrated spin-1 Blume-Capel model on an infinite sawtooth chain is exactly solved by the transfer matrix method. The magnetization, ground-state phase diagram, magnetocaloric properties, and specific heat of the system are investigated. The results indicate that: (i) Magnetization plateaus appear at zero temperature. Their number depends on the sign of the crystal field D. For D≥0 there are two magnetization plateaus; however, for D

Our study indicates suspended water films, driven by crossed square-wave electric fields, may act as “washers”, “centrifuges” and “mixers”. Based on our recent model successfully describing experimentally observed electro-hydrodynamical flows in water films, we derive conditions for generating specific rotational flows. Our main findings, which are advantageous for microfluidic devices and basic research, are as follows: (1) the film’s rotational patterns depend on the phase difference $$\Updelta\varphi$$ and frequencies f of the applied fields. (2) For $$\Updelta\varphi=\pi/2$$ and $$f\sim10^{-1}-10^{0}$$ Hz, the film exhibits symmetrical reciprocating rotations, i.e. it constitutes a washer. (3) For $$\Updelta\varphi=0$$ and any f, it exhibits an ordinary anticlockwise (or clockwise) rotation, i.e. it constitutes a centrifuge or motor. (4) For $$\Updelta\varphi$$ with other values and f below 1 Hz, it exhibits asymmetrical reciprocating rotations, it constitutes an asymmetrical mixer.

Illegal logging is a pervasive problem due to lack of effective monitoring methods. A novel wireless method for illegal logging is proposed which leverage the RSSI ranging and communication of WSN and GPRS. The node displacement incurred by tree’s falling down can be detected in time. Furthermore, failure of target node can be judged with its neighbor cooperation. The effectiveness and efficiency of this system was verified in our test-bed. Thus this solution has several characteristics such as lower power, remote, lower cost, real-time and non-intrusive，which are very appropriate to protect rare trees continuously.

Whether Simvastatin has beneficial effect on pulmonary artery hypertension (PAH) remains unclear. This study aimed to explore the effect of simvastatin on PAH and the underlying mechanism. Male SD rats were randomized into three groups: control group, PAH model group, and treatment group with the intervention of the Simvastatin (n = 10, each group). Rat PVSMCs were isolated from pulmonary artery, cultured in vitro, and subjected to different treatment with PDGF, and/or Simvastatin or parthenolide. The mean pulmonary arterial pressure (mPAP), endomembrane proliferation in the pneumono-arteriole, and scores of the average angiemphraxis (VOS) were measured. The expression of NF-κB at mRNA and protein levels in the artery and PVSMCs was evaluated by fluorescent quantitative PCR, immunohistochemistry, and Western blot. Our results showed that mPAP, endomembrane proliferation in the pneumono-arteriole and VOS increased significantly in PAH model group compared with control group (P < 0.05). NF-κB expression was significantly higher in PAH model group than control group (P < 0.05), and also higher in the stimulated PVSMCs than control PVSMCs (P < 0.05). With the intervention of simvastatin, mPAP, endomembrane proliferation in the pneumono-arteriole and VOS decreased dramatically, compared with model group (P < 0.05). NF-κB expression was significantly decreased in both the artery and PVSMCs (P < 0.05). In conclusion, our study provides experimental evidence that NF-κB plays an important role in the occurrence of pulmonary artery hypertension and Simvastatin has beneficial effect on pulmonary artery hypertension by inhibiting the expression of NF-κB.

To explore the effects of NF-κB on proliferation of rat pulmonary artery smooth muscle cells (PASMC) inhibited by simvastatin.PASMC isolated from rats and cultured in vitro were randomly divided into four groups (n=6 each): control, platelet-derived growth factor (PDGF) treatment, PDGF+simvastatin treatment, and PDGF+simvastatin+parthenolide (NF-κB inhibitor) treatment. MTT colorimetric assay and flow cytometry were performed to detect cell proliferation and cell cycle distribution. Immunohistochemistry was performed to detect the expression of NF-κB protein. Real-Time PCR was performed to detect NF-κB mRNA expression.Compared with the control group, MTT values of PASMC at all time points, cell proportion at the S phase and G2+M phase, NF-κB protein and mRNA expression increased significantly in the PDGF group (P0.05). With the intervention of simvastatin, the levels of above indexes decreased compared with the PDGF group (P0.05). With the intervention of simvastatin and parthenolide, the levels of above indexes decreased more obviously, but were not significantly different from those in the simvastatin intervention group.Simvastatin can inhibit proliferation of PASMC and cell cycle process. NF-κB may play an important role in the inhibitory effect of simvastatin on the proliferation of PASMC.

Objective Stroke volume variation (SVV) is a reliable predictor of fluid responsiveness in adult patients. However, the predictive value of SVV is uncertain in pediatric patients. We performed the first systematic meta-analysis to evaluate the diagnostic value of SVV in predicting fluid responsiveness in children. Methods PUBMED, EMBASE, and Cochrane Central Register of Controlled Trials were searched up to December 2016. Original studies assessing the diagnostic accuracy of SVV in predicting fluid responsiveness in children were considered to be eligible. A random-effects model was used to calculate pooled values of sensitivity, specificity and diagnostic odds ratio with 95% CI. The summary receiver operating characteristic curve was estimated and area under the curve was calculated. Quality of the studies was assessed with the QUADAS-2 tool. Results Six studies with a total of 279 fluid boluses in 224 children were included. The analysis demonstrated a pooled sensitivity of 0.68 (95% CI,0.59–0.76), pooled specificity of 0.65 (95% CI, 0.57–0.73), pooled diagnostic odds ratio of 8.24 (95% CI, 2.58–26.30), and the summary area under the summary receiver operating characteristic curve of 0.81. However, significant inter-study heterogeneity was found (p

A new approach for exploring effects of interfaces on polar liquids is presented. Their impact on the polar liquid film motor (PLFM) – a novel micro-fluidic device – is studied. We account for the interface's impact by modeling slip boundary effects on the PLFM's electro-hydro-dynamical rotations. Our analytical results show as increases (with denoting the slip length resulting from the interface's impact on the film's properties, k > -1 and R denoting the film's radius): (a) PLFMs subsequently exhibit rotation characteristics under "negative-", "no-", "partial-" and "perfect-" slip boundary conditions; (b) The maximum value of the linear velocity of the steady rotating film increases linearly and its location approaches the film's border; (c) The decay of the angular velocities' dependency on the distance from the center of the film slows down, resulting in a macroscopic flow near the boundary. With our calculated rotation speed distributions consistent with the existing experimental ones, research aiming at fitting computed to measured distributions promises identifying the factors affecting , e.g., solid-fluid potential interactions and surface roughness. The consistency also is advantageous for optimizing PLFM's applications as micro-washers, centrifuges, mixers in the lab-on-a-chip.

We investigate the quantum correlation measured by quantum discord (QD) for thermalized ferromagnetic Heisenberg spin systems in one-dimensional chains and on fractal lattices using the decimation renormalization group approach. It is found that the QD between two non-nearest-neighbor end spins exhibits some interesting behaviors which depend on the anisotropic parameter Δ, the temperature T, and the size of system L. With increasing Δ continuously, the QD possesses a cuspate change at Δ = 0 which is a critical point of quantum phase transition (QPT). There presents the “regrowth” tendency of QD with increasing T at Δ 0. As the size of the system L becomes large, there still exists considerable thermal QD between long-distance end sites in spin chains and on the fractal lattices even at unentangled states, and the long-distance QD can spotlight the presence of QPT. The robustness of QD on the diamond-type hierarchical lattices is stronger than that in spin chains and Koch curves, which indicates that the fractal can affect the behaviors of quantum correlation.

To study risk factors for severe hand, foot and mouth disease (HFMD) complicated by heart and lung failure and treatment experience.A total of 198 children with severe HFMD between March and August in 2011 were enrolled. Univariate analysis and logistic regression model were used to analyze the risk factors severe HFMD complicated by heart and lung failure. The effects of combination therapy with immunoglobulin+dexamethasone+ribavirin were observed.Univariate analysis indicated that HFMD patients with heart and lung failure had higher proportions of consciousness, tachypnoea, abnormal hemodynamics, increased troponin and EV71 infection than HFMD patients without heart and lung failure (P0.05).Multivariate logistic regression analysis indicated that tachypnoea, abnormal hemodynamics and EV71 infection were the main risk factors for heart and lung failure. Compared with combination therapy with dexamethasone+ribavirin, combination therapy with immunoglobulin+dexamethasone+ribavirin was more effective for preventing hemodynamic changes in children with severe HFMD (P0.01). Compared with HFMD patients with heart and lung failure, the effect of the combination therapy with immunoglobulin+dexamethasone+ribavirin was better in HFMD patients without heart and lung failure (P0.01).The main risk factors for heart and lung failure in children with severe HFMD include tachypnoea, abnormal hemodynamics and EV71 infection. Early combination therapy with immunoglobulin+dexamethasone+ribavirin can reduce the incidence of heart and lung failure in children with severe HFMD.

To study the relationship of varicocele (VC) with the expressions of T-type channel alpha1H and alpha1G in the sperm of VC patients.Based on the WHO criteria, we examined the semen samples by computer-aided sperm analysis (CASA), and divided the samples into groups A (normal semen from volunteers, n = 20), B (normal semen from VC patients, n = 16) and C (abnormal semen from VC patients, n = 44). We optimized the semen by discontinuous Percoll grade centrifugation, and determined the mRNA expressions of T-type channel alpha1H and alpha1G in the three groups using using reverse transcription polymerase chain reaction (RT-PCR).Compared with group A, the mRNA expressions of alpha1H and alpha1G showed with no significant decrease in group B (P0.05), but were remarkably reduced in group C (P0.01).The abnormal mRNA expressions of T-type channel alpha1H and alpha1G may be one of the causes of declined semen quality and consequently infertility in VC patients, which has pointed out a new direction for the studies of the causes and treatment of VC-related infertility.

To explore the influence of inhibiting Notch signal on pulmonary vascular remodeling induced by PDGF.Vessel strips taken from healthy Wistar rats were cultured together with extrogenous PDGF, the potent smooth muscle cell proliferation stimulators, for 7 days. Some vessel strips were cultured with PDGF and gamma-secretase inhibitor DAPT, a Notch signaling inhibitor for 7 days. Vascular wall thickness, PCNA and caspase-3 positive cell rate were examined in vessel strips. The alterations of Notch 1 to 4 receptor and HERP1, 2 mRNA were discerned by FQ-PCR to observe the influence of DAPT on Notch signal. At the same time, above indexes, which were related with pulmonary vascular remodeling, were measured too.PDGF stimulation in the cultured normal pulmonary arteries resulted in vascular medial thickness increase for about 50%, accompanied by significant increase in PCNA positive cell rate and decrease of caspase-3 positive cell rate. When DAPT were added to inhibit Notch signaling, the expression of HERP1, 2 mRNA decreased, the degrees of PDGF induced vascular medial thickness and PCNA positive cell rate increase as well as caspase-3 positive cell rate decrease were all attenuated notably.Inhibiting Notch signal induced by gamma-secretase inhibitor lead to the suppression of pulmonary vascular remodeling induced by PDGF, suggesting inhibition of Notch signal pathway might be a novel strategy in the intervention of pulmonary hypertension.

The "liquid film motor," a novel device with important implications for basic research and technology, is analyzed. It works perfectly with both direct current (dc) and alternating current (ac) fields. We develop a mathematical model describing electrohydrodynamical (EHD) motions induced by ac fields, which are more complex and have wider technological applications than those produced by dc fields. The main characteristics of these motions, derived in our paper and in full agreement with the experimental ones, are as follows: (i) Rotation of the film requires that the frequencies of the ac fields are exactly the same and their magnitudes surpass a threshold, which depends on their phase difference. (ii) Vibrations may be induced by fields with different frequencies. (iii) The EHD motions strongly depend on the polarization induced by the external electric field. However, these motions are little affected by the liquid's electrical conductivity, viscosity, dielectric constant, and density. Our model also predicts several features, which have yet to be experimentally verified.

The paper presents a simple dynamical model to systemically explain the rotation mechanism of the liquid film motor reported by experiments. The field-induced-plasticity effect of the liquid film is introduced into our model, in which the liquid film in crossed electric fields is considered as a Bingham plastic fluid with equivalent electric dipole moment. Several analytic results involving the torque of rotation, the scaling relation of the threshold fields, and the dynamics equation of a square film and its solution are obtained. We find that the rotation of the liquid film motor originates from the continuous competition between the destruction and the reestablishment of the polarization equilibrium maintained by the external electric field, which is free from the boundary effects. Most experimental phenomena observed in direct current electric fields are interpreted well.

To identify the gene expression profiles associated with the apoptosis of pulmonary arterial smooth muscle cells stimulated by carbon monoxide (CO).Primary cultured Sprague-Dawley rat pulmonary arterial smooth muscle cells (PASMC) were stimulated by platelet-derived growth factor (PDGF, 20 ng/mL) and hemin (20 μmol/L). Cells were harvested after 2 hrs and Affymetrix microarrays were used to detect the gene expression profile.Some genes associated with Map2k3 (P38) signal pathway, such as CyclinD1, CyclinH, CyclinL1, MAP2K3, Kras and Nras, were upregulated, but P27 expression was downregulated after PDGF treatment. After endogenous CO treatment, some genes associated with P53 pathway, such as Gadd45α, P21 and Trp53inp1, were upregulated.P53 pathway probably plays an important role in apoptosis of pulmonary arterial smooth muscle cells treated with endogenous CO.

The effect of alkaline thermal hydrolysis method on excess sludge and its characteristic parameters(such as soluble chemical oxygen demand, volatile fatty acids, ammonia-nitrogen, pH value, sludge concentration, etc.) were investigated. The results show that the addition of alkali can reduce the resistance of the sludge cells to high temperature and enhance the release and the hydrolysis of organic materials from the sludge cells with the increase of temperature, pH value and reaction time. The concentration of SCOD reached 17,950 mg/L and SCOD/TCOD was 0.65 on the conditions of pH 13, 170 degrees C and 75 min. The maximal dissolving rate of suspended solids (SS) was 67% and 72% for volatile suspended solids (VSS) at pH 13 with 60 min. The concentration of SCOD after alkaline thermal hydrolysis treatment increased with the increase of sludge concentration, in which the nice linear relation was reached and the correlation coefficient (R2) was above 0.97. The increasing rate of the SCOD was improving with the increase of the pH value and the SCOD of unit sludge reached 672 mg/g at pH 13. The effect of three factors on the SCOD was investigated through orthogonal experiment at the temperature of 170 degrees C, the importance was sludge concentration,pH value and reaction time in turn.

The dynamics of the one-dimensional random transverse Ising model with both nearest-neighbor (NN) and next-nearest-neighbor (NNN) interactions is studied in the high-temperature limit by the method of recurrence relations. Both the time-dependent transverse correlation function and the corresponding spectral density are calculated for two typical disordered states. We find that for the bimodal disorder the dynamics of the system undergoes a crossover from a collective-mode behavior to a central-peak one and for the Gaussian disorder the dynamics is complex. For both cases, it is found that the central-peak behavior becomes more obvious and the collective-mode behavior becomes weaker as $K_{i}$ increase, especially when $K_{i}>J_{i}/2$ ($J_{i}$ and $K_{i}$ are exchange couplings of the NN and NNN interactions, respectively). However, the effects are small when the NNN interactions are weak ($K_{i}, Comment: 15 pages,5 figures.Submitted to Journal of Physics: Condensed Matter

The effects of Gaussian disorder on the dynamics of the one-dimensional spin-1/2 random transverse Ising model are studied in the high-temperature limit by the recursion method. Both spin autocorrelation functions and the corresponding spectral densities are calculated for three types of disordered cases. It is found that when the standard deviation ${\ensuremath{\sigma}}_{J}$ of the exchange coupling (or the standard deviation ${\ensuremath{\sigma}}_{B}$ of the random transverse field) is small, the dynamics of the system undergoes two crossovers in sequence as the mean value of the exchange coupling (or the random transverse field) varies: from a central-peak behavior to a collective-mode one, and then to the precession of free spins in an external transverse magnetic field. However, when ${\ensuremath{\sigma}}_{J}$ or ${\ensuremath{\sigma}}_{B}$ are large enough, there is no crossover, i.e., the dynamics of the system shows a central-peak behavior and a disordered behavior, respectively.

The dynamical properties of one-dimensional random transverse Ising model (RTIM) with a double-Gaussian disorder is investigated by the recursion method. Based on the first twelve recurrences derived analytically, the spin autocorrelation function (SAF) and associated spectral density at high temperature were obtained numerically. Our results indicate that when the standard deviation σJ (or σB) of the exchange couplings Ji (or the random transverse fields Bi) is small, no long-time tail appears in the SAF. The spin system undergoes a crossover from a central-peak behavior to a collective-mode behavior, which is the dynamical characteristics of RTIM with the bimodal disorder. However, when σJ (or σB) is large enough, the system exhibits similar dynamics behaviors to those of the RTIM with the Gaussian disorder, i.e., the system exhibits an enhanced central-peak behavior for large σJ or a disordered behavior for large σB. In this instance, SAFs exhibit a similar long-time tail, i.e., C(t) ~ t−2 for large t. Similar properties are obtained when Ji (or Bi) satisfy the double-exponential distribution or the double-uniform distribution. Besides, when both the standard deviations and the mean values of the exchange couplings are small, the effects of the Gaussian random bonds may drive the system undergo two crossovers from a triplet state to a doublet state, and then to a collective-mode state.

The density distribution of ultracold two-component fermionic gases 6Li, which are confined in a gradient magnetic field and a symmetrical double-well potential, is investigated by employing local-density approximation. It is found that three different regimes including quasi-molecular Bose—Einstein condensation (BECm), the dimers in the unitarity limit (ULd), and Bardeen—Cooper—Schrieffer superfluid (BCS) can coexist at the same time. Furthermore, the ranges of these regimes can be controlled to some extent by tuning the gradient of the magnetic field and the parameters characterizing the properties of the double-well potential. This study is of guidance and significance for experimentally realizing the coexistence of BECm, ULd, and BCS in the double-well potential.

Hereditary multiple exostoses (HME) is an autosomal-dominant disorder characterized by the presence of bony outgrowths on the long bones. In this report, we describe a Chinese family with HME. Linkage analysis and mutation detection were performed. Linkage with the EXT2 was established in this family. A novel mutation, EXT2 c239-244delG, was identified. Mutation analysis in a family with HME allows for genetic counseling and prenatal diagnosis.