Negative thermal expansion and phase transition of low-temperature Mg_(2)NiH_(4)

The negative thermal expansion(NTE) phenomenon is of great significance in fabricating zero thermal expansion(ZTE) materials to avoid thermal shock during heating and cooling. NTE is observed in limited groups of materials, e.g., metal cyanides, oxometallates, and metalorganic frameworks, but has not been reported in the family of metal hydrides. Herein, a colossal and continuous negative thermal expansion is firstly developed in the low-temperature phases of LT1-and LT2-Mg_(2)NiH_(4) between 488 K and 733 K from in-situ transmission electron microscope(TEM) video, with the volume contraction reaching 18.7% and 11.3%, respectively. The mechanisms for volume contraction of LT1 and LT2 phases are elucidated from the viewpoints of phase transformation, magnetic transition, and dehydrogenation, which is different from common NTE materials containing flexible polyhedra units in the structure. The linear volume shrinkage of LT2 in the temperature of 488-553 K corresponds to the phase transition of LT2→HT with a thermal expansion coefficient of -799.7 × 10^(-6) K^(-1) revealed by in-situ synchrotron powder X-ray diffraction. The sudden volume contraction in LT1 between 488 and 493 K may be caused by the rapid dehydrogenation of LT1 to Mg_(2)Ni. The revealed phenomenon in single composite material with different structures would be significant for preparing zero thermal expansion materials by tuning the fraction of LT1 and LT2 phases.

Evolution law of a negative binomial state in an amplitude dissipative channel

For the first time we derive the evolution law of the negative binomial state In） （nI in an ampli-tude dissipative channel with a damping constant to. We find that after passing through the channel, the final state is still a negative binomial state, however the parameter γ evolves into The decay law of theaverage photon number is also obtained.

Wigner function for squeezed negative binomial state and evolution of density operator for amplitude decay

Using the thermal-entangled state representation and the operator-ordering method, we investigate Wigner function(WF) for the squeezed negative binomial state(SNBS) and the analytical evolution law of density operator in the amplitude decay channel.The results show that the analytical WF is related to the square of the module of single-variable Hermite polynomials, which leads to a new two-variable special function and its generating function, and the parameters s and γplay opposite roles in the WF distributions.Besides, after undergoing this channel, the initial pure SNBS evolves into a new mixed state related to two operator Hermite polynomials within normal ordering, and fully loses its nonclassicality and decays to vacuum at long decay time.

Negative Binomial Distribution Based Reputation Direct Update for Wireless Sensor Networks

In the reputation modeling of wireless sensor networks（WSNs） many literatures have proposed creative reputation indirect update methods,such as reputation integration,discounting,aging to eliminate,and filtering malicious reputation information. However,few have discussed the reputation direct update. In this paper,based on sound statistical theories,a negative binominal distribution method in the reputation direct update for WSNs is proposed. Results show that the proposed method is more suitable and time-saving for the reputation update of the resource constraint WSNs and can improve the computation power efficiency as well.

Zero-inflated non-central negative binomial distribution

In this article, the zero-inflated non-central negative binomial(ZINNB) distribution is introduced. Some of its basic properties are obtained. In addition, we use the maximum likelihood estimation method to estimate the parameters of the ZINNB distribution, and illustrate its application by fitting the actual data sets.

Stochastic Orders Comparisons of Negative Binomial Distribution with Negative Binomial—Lindley Distribution

The purpose of this study is to compare a negative binomial distribution with a negative binomial—Lindley by using stochastic orders. We characterize the comparisons in usual stochastic order, likelihood ratio order, convex order, expectation order and uniformly more variable order based on theorem and some numerical example of comparisons between negative binomial random variable and negative binomial—Lindley random variable.

On a Characterization of Zero-Inflated Negative Binomial Distribution

Zero-inflated negative binomial distribution is characterized in this paper through a linear differential equation satisfied by its probability generating function.

A First Order Stationary Branching Negative Binomial Autoregressive Model with Application

In the area of time series modelling, several applications are encountered in real-life that involve analysis of count time series data. The distribution characteristics and dependence structure are the major issues that arise while specifying a modelling strategy to handle the analysis of those kinds of data. Owing to the numerous applications there is a need to develop models that can capture these features. However, accounting for both aspects simultaneously presents complexities while specifying a modeling strategy. In this paper, an alternative statistical model able to deal with issues of discreteness, overdispersion, serial correlation over time is proposed. In particular, we adopt a branching mechanism to develop a first-order stationary negative binomial autoregressive model. Inference is based on maximum likelihood estimation and a simulation study is conducted to evaluate the performance of the proposed approach. As an illustration, the model is applied to a real-life dataset in crime analysis.

Time evolution of negative binomial optical field in a diffusion channel

We find the time evolution law of a negative binomial optical field in a diffusion channel. We reveal that by adjusting the diffusion parameter, the photon number can be controlled. Therefore, the diffusion process can be considered a quantum controlling scheme through photon addition.

Non-anthracycline-containing docetaxel and cyclophosphamide regimen is associated with sustained worse outcome compared with docetaxel, anthracycline and cyclophosphamide in neoadjuvant treatment of triple negative and HER2-positive breast cancer patients:

Objective： A previous study demonstrated that non-anthracycline-containing docetaxel plus cyclophosphamide（TC） regimen was inferior to docetaxel, anthracycline and cyclophosphamide（TAC） in neoadjuvant treatment of triple-negative breast cancer（TNBC） and human epidermal growth factor receptor-2-（HER2）-positive breast cancer in a short-term follow-up. Herein, long-term follow-up survival outcomes have been investigated.Methods： TNBC or HER2-positive patients were randomized to receive 6 cycles of TC or TAC neoadjuvant treatment. The primary endpoint was pathological complete remission（p CR）. Secondary endpoints included clinical response rate, event-free survival（EFS）, and overall survival（OS）.Results： A cohort of 96 patients consisted of 45 in TC and 51 in TAC arm. With a median follow-up period of53（range, 8-76） months, the patients achieving p CR post neoadjuvant chemotherapy exhibited superior EFS and OS than patients without p CR（P〈0.05）. TAC treatment resulted in consistently better EFS than TC treatment：the estimated 5-year EFS was 66.1% vs. 29.8%（P=0.002）. Moreover, the estimated 5-year OS was also in favor of TAC： 88.4% vs. 51.6%（P〈0.001）. Multivariable analysis demonstrated that the treatment regimen was an independent prognostic factor, and patients treated with TAC had a superior EFS [hazard ratio（HR）, 0.48; 95%confidence interval（95% CI）, 0.26-0.90; P=0.021] and OS（HR, 0.20; 95% CI, 0.08-0.60; P=0.003）.Conclusions： The updated long-term follow-up data demonstrated a sustained benefit in EFS and OS from anthracycline-containing TAC treatment, indicating that anthracycline is an essential and effective drug in this clinical trial.

Changes of Serum Insulin-like Growth Factor-2 Response to Negative Symptom Improvements in Schizophrenia Patients Treated with Atypical Antipsychotics

Accumulating evidence suggests that a disruption of early brain development,in which insulin-like growth factor-2(IGF-2)has a crucial role,may underlie the pathophysiology of schizophrenia.Our previous study has shown that decreased serum IGF-2 was correlated with the severity of psychopathology in patients with schizophrenia.Here we conducted a prospective observation trial to investigate the effects of atypical antipsychotics on serum IGF-2 level and its relationship with clinical improvements in schizophrenia patients.Thirty-one schizophrenia patients with acute exacerbation and 30 healthy individuals were recruited in this study.Psychiatric symptoms were assessed using the Positive and Negative Syndrome Scale(PANSS)and serum IGF-2 levels were determined using ELISA.We found that schizophrenia patients with acute exacerbation had lower serum IGF-2 levels than control individuals at baseline(P<0.05).After 2 months of atypical antipsychotic treatment,a significant improvement in each PANSS subscore and total score was observed in patients(all P<0.01),and the serum IGF-2 levels of patients were significantly increased compared with those at baseline(203.13±64.62 vs.426.99±124.26 ng/mL;t=−5.044,P<0.001).Correlation analysis revealed that the changes of serum IGF-2 levels in patients were significantly correlated with the improvements of negative symptoms(r=−0.522,P=0.006).Collectively,our findings demonstrated changes of serum IGF-2 response to improvements of negative symptoms in schizophrenia patients treated with atypical antipsychotics,suggesting that serum IGF-2 might be a treatment biomarker for schizophrenia.

Characterization of the negative thermal expansion material Zr_(1-x)Hf_xW_2O_8

The oxide ZrW_2O_8 displays unusual property of isotropic negative thermalexpansion in a large wide temperature range, which makes it have a number of important potentialapplications. The cubic Zr_(1-x)Hf_xW_2O_8 (x velence 0,0.3, 0.5, 0.7, and 1.0) were synthesized bystandard solid state reaction technique. The high and low temperature X-ray diffraction analysisindicate that the substitution of the Hf^(4+) for Zr^(4+) only leads to reducing the latticeconstants, and the changes of negative thermal expansion coefficients are not obvious. The linearexpansion coefficients of Zr_(1-x)Hf_xW_2O_8 (x velence 0,0.3, 0.5, 0.7, and 1.0) are about -6 X 10^(-6) K^(-1) in the temperature range of 298 to 973 K, while that of Zr_(0.5)Hf_(0.5)W_2O_8 is -9.6X 10^(-6) K_(-1) from 83 to 298 K. The phase transition temperatures from alpha-ZrW_2O_8 tobeta-ZrW_2O_8 structure were also determined by X-ray diffraction method. Thermogravimetric analysis(TGA) exhibits that Zr_(1-x)Hf_xW_2O_8 is not hygroscopic in air.

Influence of Negative Bias Voltage on the Mechanical and Tribological Properties of MoS_2/Zr Composite Films

MoS2/Zr composite films were deposited on the cemented carbide YT14 （WC＋14%TiC＋6%Co） by medium-frequency magnetron sputtered and coupled with multi-arc ion plated techniques.The influence of negative bias voltage on the composite film properties,including adhesion strength,micro-hardness,thickness and tribological properties were investigated.The results showed that proper negative bias voltage could significantly improve the mechanical and tribological properties of composite films.The effects of negative bias voltage on film properties were also put forward.The optimal negative bias voltage was -200 V under this experiment conditions.The obtained composite films were dense,the adhesion strength was about 60 N,the thickness was about 2.4 μm,and the micro-hardness was about 9.0 GPa.The friction coefficient and wear rate was 0.12 and 2.1×10-7 cm3/N·m respectively after 60 m sliding operation against hardened steel under a load of 20 N and a sliding speed of 200 rev·min-1.

Negative differential resistance and quantum oscillations in FeSb_2 with embedded antimony

We present a systematical study on single crystalline FeSb2 using electrical transport and magnetic torque measurements at low temperatures. Nonlinear magnetic field dependence of Hall resistivity demonstrates a multi-carrier transport instinct of the electronic transport. Current-controlled negative differential resistance(CC-NDR) observed in currentvoltage characteristics below ～ 7 K is closely associated with the intrinsic transition ～ 5 K of FeSb2, which is, however,mediated by extrinsic current-induced Joule heating effect. The antimony crystallized in a preferred orientation within the FeSb2 lattice in the high-temperature synthesis process leaves its fingerprint in the de Haas-Van Alphen(dHvA) oscillations, and results in the regular angular dependence of the oscillating frequencies. Nevertheless, possible existence of intrinsic non-trivial states cannot be completely ruled out. Our findings call for further theoretical and experimental studies to explore novel physics on flux-free grown FeSb_2 crystals.

Negative Thermal Expansion of the Dy_2Fe_(16)Cr Compound

Structural, thermal expansion, and magnetic properties of the Dy_2Fe_(16)Cr compound are investigated by means of x-ray diffraction and magnetization measurements. The Dy_2Fe_(16)Cr compound has a hexagonal Th_2Ni_(17)-type structure. There exists a negative thermal expansion resulting from a strong spontaneous magnetostriction in the magnetic state of the Dy_2Fe_(16)Cr compound. The average thermal expansion coefficient is-0.794 × 10^(-5)/K in the temperature range 292–407 K. The spontaneous magnetostrictive deformation and the Curie temperature are discussed.

Chidamide Combined with Paclitaxel Liposome for the Treatment of Advanced HER2-negative Breast Cancer in Clinical Study

The purpose of this study was to investigate the efficacy and safety of chidamide combined with paclitaxel liposome in the treatment of advanced HER-2-negative breast cancer.First,41 patients with advanced HER-2-negative breast cancer who had received two chemotherapy regimens from May 2017 to November 2017 were randomly selected to receive chidamide combined with paclitaxel liposome treatment(observation group,n=20)or placebo combined with paclitaxel liposome treatment(control group,n=21).The treatment scheme of the observation group was oral chidamide 30mg twice a week for 2 months.In addition,on day 1,the patients were given paclitaxel liposome orally and intravenously administered with 175 mg/m2 for 1 cycle for 21 days and 3 cycles of chemotherapy.The treatment scheme of the control group was oral placebo 30 mg twice a week for 2 months.In addition,the method of paclitaxel liposome administration was the same as the observation group.The response rate(RR),disease control rate(DCR),and progression-free survival(PFS)were compared between the two groups.The results showed that all the 41 patients could be evaluated.In the observation group,CR5,PR7,SD5 and PD3 were obtained.RR was 60.0%and DCR was 85.0%.In the control group,CR3,PR3,SD5 and PD10 were obtained.RR was 28.6%and DCR was 52.4%.RR and DCR in the observation group were better than those in the control group,and the difference was statistically significant(P<0.05).The median PFS of the observation group was 5.2 months,longer than that of the control group(3.1 months,P<0.05).The main adverse reactions in the two groups were gastrointestinal reactions and bone marrow suppression,with grade 1~2 as the main ones.The incidence of leukopenia,thrombocytopenia and nausea and vomiting in the observation group was higher than that in the control group(P<0.05).Therefore,the chidamide combined with paclitaxel liposome is effective in the treatment of advanced HER-2-negative breast cancer,and the adverse reactions can be tolerated.

Numerical Study on Comparison of Negative and Positive Surface Discharge in c-C_(4)F_(8)/CF_(3)I/CO_(2) Gas Mixture

The dynamics of negative surface discharges in c-C_(4)F_(8)/CF_(3)I/CO_(2) gas mixture is investigated here with a 2D fuid model.The distributions of ion concentration,electric field strength and photon flux during the propagation of the streamer are obtained by solving the drift-diffusion equations of particles and Poisson's equation,and the photon flux variation function during the propagation is also fitted.It is found that the streamer branches occur when the streamer transitions from the upper surface of the insulator to the side surface,and then when the streamer approaches the plane electrode,the photon flux will increase significantly.On this basis,the positive and negative surface discharge models are compared in terms of streamer characteristics,particle characteristics and streamer branches.It is found that the streamer has a higher electron concentration and electric field in the positive model.The streamer develops“floating”in the positive surface discharge,while it is close to the surface of the insulator in the negative model.In addition,the negative streamer branch has a wider width and develops further.

A Preliminary Investigation of Arctic Sea Ice Negative Freeboard from in-situ Observations and Radar Altimetry

The negative freeboard of sea ice(i.e., the height of ice surface below sea level) with subsequent flooding is widespread in the Southern Ocean, as opposed to the Arctic, due to the relatively thicker ice and thinner snow. In this study, we used the observations of snow and ice thickness from 103 ice mass balance buoys(IMBs) and NASA Operation IceBridge Aircraft Missions to investigate the spatial distribution of negative freeboard of Arctic sea ice. The Result showed that seven IMBs recorded negative freeboards, which were sporadically located in the seas around Northeast Greenland, the Central Arctic Ocean, and the marginal areas of the Chukchi–Beaufort Sea. The observed maximum values of negative freeboard could reach-0.12 m in the seas around Northeast Greenland. The observations from IceBridge campaigns also revealed negative freeboard comparable to those of IMBs in the seas around North Greenland and the Beaufort Sea. We further investigated the large-scale distribution of negative freeboard using NASA CryoSat-2 radar altimeter data, and the result indicates that except for the negative freeboard areas observed by IMBs and IceBridge, there are negative freeboards in other marginal seas of the Arctic Ocean. However, the comparison of the satellite data with the IMB data and IceBridge data shows that the Cryosat-2 data generally overestimate the extent and magnitude of the negative freeboard in the Arctic.

Effects of extended lymphadenectomy and postoperative chemotherapy on node-negative gastric cancer

AIM:To investigate the effects of extended lymphadenectomy and postoperative chemotherapy on gastric cancer without lymph node metastasis.METHODS:Clinical data of 311 node-negative gastric cancer patients who underwent potentially curative gastrectomy with more than 15 lymph nodes resected,from January 2002 to December 2006,were analyzed retrospectively.Patients with pT4 stage or distant metastasis were excluded.We analyzed the relationship between the D2 lymphadenectomy and the 5-year survival rate among different subgroups stratified by clinical features,such as age,tumor size,tumor location and depth of invasion.At the same time,the relationship between postoperative chemotherapy and the5-year survival rate among different subgroups were also analyzed.RESULTS:The overall 5-year survival rate of the entire cohort was 63.7%.The 5-year survival rate was poor in those patients who were:(1)more than 65 years old;(2)with tumor size larger than 4 cm;(3)with tumor located in the upper portion of the stomach;and(4)with pT3 tumor.The survival rate was improved significantly by extended lymphadenectomy only in patients with pT3 tumor(P=0.019),but not in other subgroups.Moreover,there was no significant difference in survival rate between patients with and without postoperative chemotherapy among all of the subgroups(P>0.05).CONCLUSION:For gastric cancer patients without lymph node metastasis,extended lymphadenectomy could improve the survival rate of those who have pT3-stage tumor.However,there was no evidence of a survival benefit from postoperative chemotherapy alone.

Entanglement properties between two atoms in the binomial optical field interacting with two entangled atoms

The temporal evolution of the degree of entanglement between two atoms in a system of the binomial optical field interacting with two arbitrary entangled atoms is investigated. The influence of the strength of the dipole–dipole interaction between two atoms, probabilities of the Bernoulli trial, and particle number of the binomial optical field on the temporal evolution of the atomic entanglement are discussed. The result shows that the two atoms are always in the entanglement state. Moreover, if and only if the two atoms are initially in the maximally entangled state, the entanglement evolution is not affected by the parameters, and the degree of entanglement is always kept as 1.