Fluorescent Double Network Hydrogels with Ionic Responsiveness and High Mechanical Properties for Visual Detection

We developed a fluorescent double network hydrogel with ionic responsiveness and high mechanical properties for visual detection.The nanocomposite hydrogel of laponite and polyacrylamide serves as the first network,while the ionic cross-linked hydrogel of terbium ions and sodium alginate serves as the second network.The double-network structure,the introduction of nanoparticles and the reversible ionic crosslinked interactions confer high mechanical properties to the hydrogel.Terbium ions are not only used as the ionic cross-linked points,but also used as green emitters to endow hydrogels with fluorescent properties.On the basis of the “antenna effect” of terbium ions and the ion exchange interaction,the fluorescence of the hydrogels can make selective responses to various ions(such as organic acid radical ions,transition metal ions) in aqueous solutions,which enables a convenient strategy for visual detection toward ions.Consequently,the fluorescent double network hydrogel fabricated in this study is promising for use in the field of visual sensor detection.

Analysis on high speed response of a uni-traveling-carrier double hetero-junction phototransistor

In this paper, the positive influence of a uni-traveling-carrier （UTC） structure to ease the contract between the respon- sivity and working speed of the InP-based double hetero-junction phototransistor （DHPT） is illustrated in detail. Different results under electrical bias, optical bias or combined electrical and optical bias are analyzed for an excellent UTC-DHPT performance. The results show that when the UTC-DHPT operates at three-terminal （3T） working mode with combined electrical bias and optical bias in base, it keeps a high optical responsivity of 34.72 A/W and the highest optical transition frequency of 120 GHz. The current gain of the 3T UTC-DHPT under 1.55-μm light illuminations reaches 62 dB. This indicates that the combined base electrical bias and optical bias of 3T UTC-DHPT can make sure that the UTC-DHPT provides high optical current gain and high optical transition frequency simultaneously.

Dynamic responses of reinforced concrete beams under double-endinitiated close-in explosion

The reinforced concrete(RC) structural component might suffer a great damage under close-in explosion.Different from distant explosions, blast loads generated by the close-in explosion are non-uniformly distributed on the structural component and may cause both local and structural failure. In this study,an experimental study was conducted to investigate the dynamic responses of RC beams under doubleend-initiated close-in explosions. The experimental results show that the distribution of blast loads generated by the double-end-initiated explosion is much more non-uniform than those generated by single-point detonation, which is caused by the self-Mach-reflection effects. A 3 D finite element model was developed and validated in LS-DYNA by employing the modified K&C model. Intensive numerical calculations were conducted to study the influences of the initiation way, scaled distance and longitudinal reinforcement ratio on the dynamic responses and failure modes of RC beams. Numerical results show that the RC beam suffers greater damage as the cylindrical explosive is detonated at its double ends than the scenario in which the cylindrical explosive is detonated at its central point. RC beams mainly suffer flexural failure and flexure-shear failure under the double-end close-in explosion, and the failure modes of RC beams change from the flexural damage to flexure-shear damage as the scaled distance or the longitudinal reinforcement ratio decreases. The direct shear failure mode is not usually observed in the double-end-initiated explosion, since the intense blast loads is basically concentrated in the midspan of RC beam, which is due to self-Mach-reflection enhancement.

Delayed response to the photovoltaic performance in a double quantum dots photocell with spatially correlated fluctuation

A viable strategy for enhancing photovoltaic performance is to comprehend the underlying quantum physical regime of charge transfer in a double quantum dots(DQD) photocell. This work explored the photovoltaic performance dependent spatially correlated fluctuation in a DQD photocell. The effects of spatially correlated fluctuation on charge transfer and output photovoltaic efficiency were explored in a proposed DQD photocell model. The results revealed that the charge transport process and the time to peak photovoltaic efficiency were both significantly delayed by the spatially correlated fluctuation, while the anti-spatially correlated fluctuation reduced the output peak photovoltaic efficiency. Further results revealed that the delayed response could be suppressed by gap difference and tunneling coefficient within two dots. Subsequent investigation demonstrated that the delayed response was caused by the spatial correlation fluctuation slowing the generative process of noise-induced coherence, which had previously been proven to improve the quantum photovoltaic performance in quantum photocells. And the reduced photovoltaic properties were verified by the damaged noise-induced coherence owing to the anti-spatial correlation fluctuation and a hotter thermal ambient environment. The discovery of delayed response generated by the spatially correlated fluctuations will deepen the understanding of quantum features of electron transfer, as well as promises to take our understanding even further concerning quantum techniques for high efficiency DQD solar cells.

Synthesis and Optical Responses of Ag@Au/Ag@Au Double Shells

We synthesize hollow-structured Ag@Au nanoparticles with single porous shell and Ag@Au/Ag@Au double shells by using the galvanic replacement reaction and investigate their linear and nonlinear optical properties. Our results show that the surface plasmon resonance wavelength of the hollow porous nanoparticles could be easily tuned in a wide range in the visible and near infrared region by controlling the volume of HAuCl4. The nonlinear optical refraction of the double-shelled Ag@Au/Ag@Au nanoparticles is prominently enhanced by the plasmon resonance. Our findings may find applications in biosensors and nonlinear optical nanodevices.

Seasonal responses of monthly mean sea levels in the Bohai Sea to hydrometeorological forcing and their double screening regression models

-In this paper, the maximum entropy spectral, the cross-spectral and the frequency response analyses are madeon the basis of the data of monthly mean sea levels at coastal stations in the Bohai Sea during 1965-1986. The results show that the annual fluctuations of the monthly mean sea levels in the Bohai Sea are the results of the coupling response of seasonal variations of the marine hydrometeorological factors. Furthermore, the regression prediction equation is obtained by using the double screening stepwise regression analysis method . Through the prediction test , it is proved that the obtained results are desirable.

Double-Lumen Needle Follicular Flushing System versus Single-Lumen Aspiration Needle in IVF/ICSI Patients with Poor Ovarian Response: A Meta-Analysis

Background: The present study performed a meta-analysis to comprehensively analyze existing randomized controlled trials (RCT) involving the use of double-lumen needle in patients with poor ovarian response to explore whether double-lumen needle was good for specific patients. Methods: The PubMed, EMBASE, Cochrane Library databases and two randomized controlled trials registration centers were thoroughly searched until April 2017. The clinical outcomes of IVF/ICSI cycles were compared between two groups with double-lumen needle and single-lumen needle. Results: Four RCT studies were included in this present meta-analysis. The oocytes yield was similar in two groups (OR 0.88, 95%CI 0.66 - 1.16;I2 = 4%). The procedure time with double-lumen needle was significantly longer than that with single-lumen needle (IV = 1.98, 95%CI 0.95 - 3.00;I2 = 86%). The fertilization rate with double-lumen needle was lower than that with single-lumen needle (OR 0.66, 95%CI 0.44 - 0.97;I2 = 0%). There was no significant difference of live birth rate in two groups (OR 0.76, 95%CI 0.32 - 1.76;I2 = 41%). Conclusion: Double-lumen needle could not benefit patients with a POR in terms of the number of oocytes retrieved, oocyte recovery rate, normal fertilization rate, clinical pregnancy rate, and live birth rate, compared with single-lumen needle.

Compromise Allocation for Combined Ratio Estimates of Population Means of a Multivariate Stratified Population Using Double Sampling in Presence of Non-Response

This paper is an attempt to work out a compromise allocation to construct combined ratio estimates under multivariate double sampling design in presence of non-response when the population mean of the auxiliary variable is unknown. The problem has been formulated as a multi-objective integer non-linear programming problem. Two solution procedures are developed using goal programming and fuzzy programming techniques. A numerical example is also worked out to illustrate the computational details. A comparison of the two methods is also carried out.

Double deck bridge behavior and failure mechanism under seismic motions using nonlinear analyzes

This paper investigates the behavior and the failure mechanism of a double deck bridge constructed in China through nonlinear time history analysis. A parametric study was conducted to evaluate the influence of different structural characteristics on the behavior of the double deck bridge under transverse seismic motions, and to detect the effect of bi- directional loading on the seismic response of this type of bridge. The results showed that some characteristics, such as the variable lateral stiffness, the foundation modelling, and the longitudinal reinforcement ratio of the upper and lower columns of the bridge pier bents have a major impact on the double deck bridge response and its failure mechanism under transverse seismic motions. It was found that the soft story failure mechanism ：is not unique to the double deck bridge and its occurrence is related to some conditions and structural characteristics of the bridge structure. The analysis also showed that the seismic vulnerability of the double deck bridge under bi-directional loading： was severely increased compared to the bridge response under unidirectional transverse loading, and out-of-phase movements were triggered between adjacent girders.

The role of NBS1 in DNA double strand break repair, telomere stability, and cell cycle checkpoint control

The genomes of eukaryotic cells are under continuous assault by environmental agents and endogenous metabolic byproducts. Damage induced in DNA usually leads to a cascade of cellular events, the DNA damage response. Failure of the DNA damage response can lead to development of malignancy by reducing the efficiency and fidelity of DNA repair. The NBS1 protein is a component of the MRE11/RAD50/NBS 1 complex （MRN） that plays a critical role in the cellular response to DNA damage and the maintenance of chromosomal integrity. Mutations in the NBS1 gene are responsible for Nijmegen breakage syndrome （NBS）, a hereditary disorder that imparts an increased predisposition to development of malignancy. The phenotypic characteristics of cells isolated from NBS patients point to a deficiency in the repair of DNA double strand breaks. Here, we review the current knowledge of the role of NBS1 in the DNA damage response. Emphasis is placed on the role of NBS1 in the DNA double strand repair, modulation of the DNA damage sensing and signaling, cell cycle checkpoint control and maintenance oftelomere stability.

Investigation on structural component behaviours of double bottom arrangement under grounding accidents

Marine accidents have caused immense casualties on various parties in shipping and shipbuilding industries, including financial and structural losses. This situation makes ship accident becomes a critical subject in naval architecture and marine structures, as it needs continuous assessment and investigation to broaden insight and data of collision and grounding phenomena. The paper aims to investigate structural conditions of a ship arranged by double hull system under accidental scenario, namely ship grounding. Fundamental concept of structure-rock interaction in poweredhard grounding is adopted to design impact configuration for calculation using finite element(FE)simulation. Involved entities are defined as the structure represented by tanker vessel, and oceanic rock is deployed as the indenter in analysis. Calculation results indicate that the crashworthiness capability of structural part strengthened by longitudinal girder is higher than other selected locations on the structures against rock penetration. Localized flooding of storage oil may occur during raking damage is formed on structural part between two girders.

Shaking table test for reinforcement of soil slope with multiple sliding surfaces by reinforced double-row anti-slide piles

Despite the continuous advancements of engineering construction in high-intensity areas,many engineering landslides are still manufactured with huge thrust force,and double-row piles are effective to control such large landslides.In this study,large shaking table test were performed to test and obtain multi-attribute seismic data such as feature image,acceleration,and dynamic soil pressure.Through the feature image processing analysis,the deformation characteristics for the slope reinforced by double-row piles were revealed.By analyzing the acceleration and the dynamic soil pressure time domain,the spatial dynamic response characteristics were revealed.Using Fast Fourier Transform and half-power bandwidth,the damping ratio of acceleration and dynamic soil pressure was obtained.Following that,the Seism Signal was used to calculate the spectral displacement of the accelerations to obtain the regional differences of spectral displacement.The results showed that the overall deformation mechanism of the slope originates from tension failure in the soil mass.The platform at the back of the slope was caused by seismic subsidence,and the peak acceleration ratio was positively correlated with the relative pile heights.The dynamic soil pressure of the front row piles showed an inverted"K"-shaped distribution,but that of the back row piles showed an"S"-shaped distribution.The predominant frequency of acceleration was 2.16 Hz,and the main frequency band was 0.7-6.87 Hz;for dynamic soil pressure,the two parameters became 1.15 Hz and 0.5-6.59 Hz,respectively.In conclusion,dynamic soil pressure was more sensitive to dampening effects than acceleration.Besides,compared to acceleration,dynamic soil pressure exhibited larger loss factors and lower resonance peaks.Finally,back row pile heads were highly sensitive to spectral displacement compared to front row pile heads.These findings may be of reference value for future seismic designs of double-row piles.

Platelet Doubling After First Decitabine Cycle Predicts Response and Survival of Myelodysplastic Syndrome Patients

Objective:Although the effect of decitabine on myelodysplastic syndrome(MDS)has been demonstrated,merely a proportion of patients respond to therapy,and no well-recognized predictors have been identified.This study was conducted to investigate the effectiveness of decitabine in real-world clinical practice,and determine the predictive factors of response and overall survival(OS)in MDS patients.

Dynamic and Static Characteristics of Double Push Rods Electromechanical Converter

Due to the influence of material characteristics and winding power, single output electromagnet has limited ability to improve the dynamic characteristic of electro-hydraulic valve. Therefore, an electromechanical converter with double push rods is proposed in this paper, which can simultaneously output two electromagnetic forces, can push or pull the valve core and sleeve according to the current direction and realize rapid operation of load. According to the electromagnetic principle and the magnetic circuit analysis method, the mathematical model and equivalent circuit of the electromechanical converter with double push rods are established. Through the finite element simulation model of the electromechanical converter with double push rods with the same magnetization directions, the changing rules of its magnetic field distribution and force–displacement behaviors are studied and analyzed. According to the analysis results, the electromagnetic mechanical parameters and mechanical structure of the electromechanical converter with double push rods are determined, and the prototype is made. The test platform for the push-pull characteristics of the electromechanical converter with double push rods is built, and its static and dynamic characteristics are tested and analyzed. The results show that the thrust and pull output characteristics of the internal and external push rods are basically consistent with the simulation output, and proportional to the current density of the coil;the push-pull hysteresis of internal and external push rods output force is less than 5%;and the dynamic time response characteristics of the displacement and force are obtained. The hysteresis e ect of output force is improved e ectively through the H bridge drive control circuit modulated by PWM. Compared with the displacement response of a singlewinding electromagnet with a similar volume, it can e ectively improve the dynamic displacement response. Followup work will further optimize the structure of the electromechanical converter and test the corresponding pilot valve. The research results provide a new theory for improving the output characteristics of electro-hydraulic pilot valve and have an extremely high engineering application value and broad application prospect.

Double diabetes in Saudi Arabia: A new entity or an underestimated condition

AIM To determine the clinical and biological characteristics of double diabetes(DD) among young people in Saudi Arabia.METHODS This was a retrospective descriptive chart review study including 312 young newly diagnosed diabetic patients(aged 12-20 years), whom were admitted over a five year period(January 2009 to December 2013). Family history of diabetes mellitus(DM)(first degree), physical body mass index(BMI), acanthosis nigricans, history of auto-immune disease and laboratory information for glycosylated hemoglobin, basal C peptide level and diabetes autoantibody response(anti-GAD, anti-IA2 and anti-ICA) were collected from medical report. A mean follow-up of 3 years for these patients was performed.RESULTS Patients were categorized into 4 groups, based on the autoantibody response(Ab+ or Ab-) and C-peptide secretion(β+ for fasting level 0.4-2.1 ng/mL and β- if < 0.4 ng/mL). Group1(type 1a): Ab+ β-(21%), group 2(type 1b): Ab- β-(9%), group 3(DD): Ab+ β+(31%)and group 4(classic type 2 DM): Ab- β+(39%). The mean age of the DD patients in our study was 15.1 ± 6.4 years. A total of 41% of the study population presented with diabetic ketoacidosis and 61% of the study population presented with positive family history of DM. The mean BMI was 26.8 kg/m2 with 64% of overweight or obese patients. Ninety two percent of the patients were started on insulin at the time of diagnosis. During a mean follow-up of 3 years, only 32% of the patients with DD required insulin and 78% were on metformin alone or with insulin. CONCLUSION Our findings enable us to arrive at the conclusion that almost one-third of the young Saudi diabetic patients reveal atypical forms of DM(double diabetes) expressing features resulting from both T1D and T2D.

模块化多电平矩阵换流器的等值阻抗模型解析分析

模块化多电平矩阵换流器(M3C)的阻抗建模是柔性低频输电系统稳定性分析和故障特性分析的关键理论基础。介绍了M3C的拓扑结构、数学模型与控制策略。在此基础上,分析了计及M3C拓扑结构特点、dq坐标变换过程和双dq分解控制的扰动电流-桥臂电压-扰动电压传递响应特性,推导了M3C等值阻抗特性与频率的关系,建立了可用固定电阻与随频率变化电抗串联表示的M3C等值阻抗数学模型。在PSCAD/EMTDC仿真平台上利用扫频法对等值阻抗理论分析的准确性进行验证,并讨论了系统控制参数、运行功率、一次参数等不同因素对M3C阻抗频率特性的影响。

超大城市乡镇场域接诉即办多主体策略行为:内在机理与困境纾解

接诉即办工作机制是健全“共建共治共享”社会治理格局的重要抓手。然而,在超大城市乡镇场域接诉即办的实践中,社会结构的复杂性、利益诉求的多元性和治理场景的多样性使得多主体策略行为频发。通过构建超大城市乡镇场域下的“结构—过程”分析框架,剖析接诉即办结构耦合、过程调试和互构互赖的运行逻辑。基于对北京市Z镇的案例分析,剖析诉求方“诉求合理化+评价负面化”策略行为、乡镇政府“风险规避+非正式简约治理”策略行为和村民委员会“变通化协商+被动执行”策略行为的深层动因,提出通过结构要素配置、增强过程统合优化和推动“结构—过程”联动共治,纾解超大城市乡镇场域接诉即办多主体策略行为双刃效应导致的困境,为中国基层治理中现实问题的解决提供理论支持。

外圈故障状态下动车组轴箱轴承振动响应影响因素分析

针对轴箱轴承故障下的动力学响应问题,将滚子设为刚性体,其他部件设为柔性体,构建了带外滚道剥落故障的双列圆锥滚子轴承的刚柔耦合有限元模型,研究了故障尺寸、故障位置以及载荷变化对轴承动态响应的影响。结果表明:刚柔耦合模型既改善了全刚性体振动响应偏大的问题,又避免了全柔性体计算时间过长的缺点;轴承的故障尺寸越大,故障位置越接近承载区,轴承载荷越大,振动信号显示出的故障特征越明显,故障尺寸达到一定程度时故障特征将由单冲击变为双冲击;径向载荷对轴承故障响应的影响远大于轴向载荷。

双条金原子链体系等离激元的激发特性

基于线性响应理论,利用能量吸收谱研究了双条金原子链体系等离激元的频率和电荷分布。结果表明,当链长相同时,双条原子链的等离激元模式比单条原子链的更容易发生耦合,表现为:单链体系大的单一能量吸收峰在双链体系时分裂为多个尖细的峰,且耦合的几个等离激元模式会出现相反的电荷极化方向。此外,无论是偶极还是四极等离激元,双条原子链最强的能量吸收峰的频率都大于单链最强能量吸收峰的频率。等离激元的尺寸效应使得同一序号的等离激元在双链体系中的频率会低于其在单链体系中的频率,且在低频率范围,双链体系的等离激元模式数要多于单链体系的模式数。

风浪流作用下双船码头系泊系统响应特性研究

在强风大浪等恶劣海况下,双船码头的系泊安全性至关重要。为确保其稳定与安全,有必要对双船码头的系泊响应特性进行深入研究。本文采用水动力软件AQWA,基于三势流理论对2艘10.5×10^(4)t散货船并排码头系泊进行数值仿真研究,得到在风流浪联合作用下不同浪向角下系泊系统动力响应特性。研究结果表明,双船并排码头系泊时,外船的运动响应大于内船;在离岸风下,系泊系统的缆绳张力较大;在向岸风下,系泊系统的护舷力较大;环境载荷同向时,缆绳张力及护舷力较大。为双船码头系泊的安全性提供了参考。