Phase-matching quantum key distribution with imperfect sources

The huge discrepancies between actual devices and theoretical assumptions severely threaten the security of quantum key distribution.Recently,a general new framework called the reference technique has attracted wide attention in defending against the imperfect sources of quantum key distribution.Here,the state preparation flaws,the side channels of mode dependencies,the Trojan horse attacks,and the pulse classical correlations are studied by using the reference technique on the phase-matching protocol.Our simulation results highlight the importance of the actual secure parameters choice for transmitters,which is necessary to achieve secure communication.Increasing the single actual secure parameter will reduce the secure key rate.However,as long as the parameters are set properly,the secure key rate is still high.Considering the influences of multiple actual secure parameters will significantly reduce the secure key rate.These actual secure parameters must be considered when scientists calibrate transmitters.This work is an important step towards the practical and secure implementation of phase-matching protocol.In the future,it is essential to study the main parameters,find out their maximum and general values,classify the multiple parameters as the same parameter,and give countermeasures.

Effect of weak randomness flaws on security evaluation of practical quantum key distribution with distinguishable decoy states

Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.

Effects of acupuncture on Alzheimer’s disease: the mechanistic study

Introduction Alzheimer’s disease(AD)is a degenerative disease of the central nervous system characterized by memory loss and cognitive impairment,often accompanied by emotional apathy,agitation,depression,delusions aggression,and other psychological symptoms[1–3].Psychological symptoms such as apathy,agitation,and depression tend to increase with the duration and severity of AD.

宁夏胃癌病例流行现状及预后5022例分析

背景宁夏地处我国西北,是我国胃癌(gastric cancer,GC)的高发区,GC位于宁夏地区恶性肿瘤死亡原因首位.但目前关于宁夏地区GC患者流行现状、分布特征及预后的大样本量的流行病学资料非常有限.目的回顾性分析5022例宁夏籍GC住院患者的临床病理资料,了解宁夏地区GC流行现状,明确影响其预后的独立危险因素.方法收集2009年至2017年在宁夏医科大学总医院住院治疗的5022例宁夏籍GC患者的临床病理资料及预后生存信息.以患者确诊日期为观察起点,以因GC死亡日期为观察终点,随访截止日期为2019-01-24,建立数据库.一般人口学资料及临床病理资料描述用率表示.Kaplan-Meier法计算中位生存时间,生存分析组间比较用log-rank法,Cox比例风险模型分析GC患者预后影响因素.通过计算危险比和95%CI计算相对风险.分析GC在该地区的流行现状,明确影响其预后的主要危险因素.结果5022例宁夏籍GC患者中,男性3888例(77.4%),女性1134例(22.6%),男女比为3.43:1,年龄范围为15-93岁,中位年龄为61(15)岁;1734例患者因GC死亡,死亡率为34.5%.GC患者死亡率随年龄增加呈增长的趋势;单因素生存分析显示,年龄、肿瘤(Tumor-Node-Metastasis,TNM)分期、肿瘤位置、大小、分化程度等是宁夏籍GC患者预后的独立危险因素,手术和术后放化疗是其保护因素;Cox生存分析显示,年龄、TNM分期、肿瘤位置、大小、分化程度均是GC患者预后的危险因素,手术和术后放化疗是其保护因素(P<0.01).结论宁夏地区GC患者以男性和老年患者为主;宁夏地区GC患者整体死亡率较高,预后较差;年龄、TNM分期、肿瘤位置等均是该地区GC患者预后的独立危险因素,手术和术后放化疗是其保护因素.

The geothermal formation mechanism in the Gonghe Basin: Discussion and analysis from the geological background

The Gonghe Basin,a Cenozoic down-warped basin,is located in the northeastern part of the Qinghai-Xizang (Tibetan) Plateau,and spread over important nodes of the transfer of multiple blocks in the central orogenic belt in the NWW direction.It is also called “Qin Kun Fork” and “Gonghe Gap”.The basin has a high heat flow value and obvious thermal anomaly.The geothermal resources are mainly hot dry rock and underground hot water.In recent years,the mechanism of geothermal formation within the basin has been controversial.On the basis of understanding the knowledge of predecessors,this paper proposes the geothermal formation mechanism of the “heat source–heat transfer–heat reservoir and caprock–thermal system”of the Gonghe Basin from the perspective of a geological background through data integrationintegrated research-expert,discussion-graph,compilation-field verification and other processes: (1) Heat source: geophysical exploration and radioisotope calculations show that the heat source of heat in the basin has both the contribution of mantle and the participation of the earth's crust,but mainly the contribution of the deep mantle.(2) Heat transfer: The petrological properties of the basin and the exposed structure position of the surface hot springs show that one transfer mode is the material of the mantle source upwells and invades from the bottom,directly injecting heat;the other is that the deep fault conducts the deep heat of the basin to the middle and lower parts of the earth's crust,then the secondary fracture transfers the heat to the shallow part.(3) Heat reservoir and caprock: First,the convective strip-shaped heat reservoir exposed by the hot springs on the peripheral fault zone of the basin;second,the underlying hot dry rock layered heat reservoir and the upper new generation heat reservoir and caprock in the basin revealed by drilling data.(4) Thermal system: Based on the characteristics of the “heat source-heat transfer-heat reservoir and caprock”,it is preliminarily believed that the Gonghe Basin belongs to the non-magmatic heat source hydrothermal geothermal system (type II21) and the dry heat geothermal system (type II22).Its favorable structural position and special geological evolutionary history have given birth to a unique environment for the formation of the geothermal system.There may be a cumulative effect of heat accumulation in the eastern part of the basin,which is expected to become a favorable exploration area for hot dry rocks.

Finite-key analysis of practical time-bin high-dimensional quantum key distribution with afterpulse effect

High-dimensional quantum resources provide the ability to encode several bits of information on a single photon,which can particularly increase the secret key rate rate of quantum key distribution(QKD) systems. Recently, a practical four-dimensional QKD scheme based on time-bin quantum photonic state, only with two single-photon avalanche detectors as measurement setup, has been proven to have a superior performance than the qubit-based one. In this paper, we extend the results to our proposed eight-dimensional scheme. Then, we consider two main practical factors to improve its secret key bound. Concretely, we take the afterpulse effect into account and apply a finite-key analysis with the intensity fluctuations.Our secret bounds give consideration to both the intensity fluctuations and the afterpulse effect for the high-dimensional QKD systems. Numerical simulations show the bound of eight-dimensional QKD scheme is more robust to the intensity fluctuations but more sensitive to the afterpulse effect than the four-dimensional one.

Effects of neutral phytase on growth performance and phosphorus utilization in crucian carp(Carassius auratus)

A feeding trial was conducted for nine weeks to investigate the effects of partially replacing Ca（H2PO4）2 with neutral phytase on the growth performance, phosphorus utilization, nutrient digestibility, serum biochemical parameters, bone and carcass mineral composition, and digestive-enzyme-specific activity in crucian carp（Carassius auratus）.The diets prepared with 0.8%, 0%, and 1.8% Ca（H2PO4）2（1%=1 g/100 g） supplements were regarded as the P1E0, negative control（NC）, and positive control（PC） groups, respectively; the other three experimental diets were prepared with the addition of 200, 300, and 500 U/kg of neutral phytase, respectively, based on the P1E0 group.Three hundred and eighty-four fish（（1.50±0.01） g） were randomly distributed in the six treatments with four replicates each.The fish were initially fed with 2%–3% diets of their body weight per day, with feeding twice daily（08：00 and 16：00）, under a 12-h light/12-h dark cycle at the temperature of（27.56±0.89） ℃.The results showed that supplemental phytase at different levels in the diet improved the final body weight, average daily gain, feed conversion ratio, phosphorus utilization, and protein efficiency ratio of crucian carp（P〈0.05）.Phytase supplementation increased the mineral content in serum（P）, bone（P, Ca）, and carcass（P, Ca, Zn, Na, and Mg）（P〈0.05）; the trypsin and chymotrypsin activity soared when fed with the phytase-supplemented diets（P〈0.05）.We may conclude that supplemental dietary neutral phytase improved the growth performance, phosphorus utilization as well as nutrient utilization in crucian carp, and it can be considered an important nutritional replacement for Ca（H2PO4）2.

Profiling and annotation combined method for multimedia application specific MPSoC performance estimation

Accurate and fast performance estimation is necessary to drive design space exploration and thus support important design decisions. Current techniques are either time consuming or not accurate enough. In this paper, we solve these problems by presenting a hybrid method for multimedia multiprocessor system-on-chip （MPSoC） performance estimation. A general coverage analysis tool GNU gcov is employed to profile the execution statistics during the native simulation. To tackle the complexity and keep the analysis and simulation manageable, the orthogonalization of communication and computation parts is adopted. The estimation result of the computation part is annotated to a transaction accurate model for further analysis, by which a gradual refinement of MPSoC performance estimation is supported. The implementation and its experimental results prove the feasibility and efficiency of the proposed method.

Characterization of β-glucosidase from Aspergillus terreus and its application in the hydrolysis of soybean isoflavones

An extracellular β-glucosidase produced by Aspergillus terreus was identified, purified, characterized and was tested for the hydrolysis of soybean isofiavone. Matrix-assisted laser desorption/ionization with tandem time-of- flight/time-of-flight mass spectrometry （MALDI-TOF/TOF MS） revealed the protein to be a member of the glycosyl hydrolase family 3 with an apparent molecular mass of about 120 kDa. The purified 13-glucosidase showed optimal activity at pH 5.0 and 65℃ and was very stable at 50℃. Moreover, the enzyme exhibited good stability over pH 3.0-8.0 and possessed high tolerance towards pepsin and trypsin. The kinetic parameters Km （apparent Michaelis- Menten constant） and Vmax （maximal reaction velocity） for p-nitrephenyl-β-D-cjlucopyranoside （pNPG） were 1.73 mmol/L and 42.37 U/mg, respectively. The Krn and Vmax for cellobiose were 4.11 mmol/L and 5.7 U/mg, respectively. The enzyme efficiently converted isoflavone glycosides to aglycones, with a hydrolysis rate of 95.8% for daidzin, 86.7% for genistin, and 72.1% for glycitin. Meanwhile, the productivities were 1.14 mmol/（L.h） for daidzein, 0.72 mmol/（L.h） for genistein, and 0.19 mmol/（L.h） for glycitein. This is the first report on the application of A. terreus β-glucosidase for converting isoflavone glycosides to their aglycones in soybean products.