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The energy density of solid-state lithium batteries (SSLBs) has been primarily limited by the low ionic conductivity of solid electrolyte and poor interface compatibility between electrolyte and electrodes. Herein, a multifunctional composite solid polymer electrolyte (CSPE) based on polyethylene oxide (PEO) embedded with zeolitic imidazolate framework-8 deposited on carboxymethyl cellulose (ZIF@CMC) is reported. The ZIF@CMC interpenetrated in PEO matrix creates a continuous Li

The Hot Universe Baryon Surveyor (HUBS) is a proposed space-based X-ray telescope for detecting X-ray emissions from the hot gas content in our universe. With its unprecedented spatially-resolved high-resolution spectroscopy and large field of view, the HUBS mission will be uniquely qualified to measure the physical and chemical properties of the hot gas in the interstellar medium, the circumgalactic medium, the intergalactic medium, and the intracluster medium. These measurements will be valuable for two key scientific goals of HUBS, namely to unravel the AGN and stellar feedback physics that governs the formation and evolution of galaxies, and to probe the baryon budget and multi-phase states from galactic to cosmological scales. In addition to these two goals, the HUBS mission will also help us solve some problems in the fields of galaxy clusters, AGNs, diffuse X-ray backgrounds, supernova remnants, and compact objects. This paper discusses the perspective of advancing these fields using the HUBS telescope., Comment: 52 pages, 22 figures. Accepted for publication in Science China: Physics, Mechanics and Astronomy

The peculiar velocities of dark matter halos are crucial to study many issues in cosmology and galaxy evolution. In this study, by using the state-of-the-art deep learning technique, a UNet-based neural network, we propose to reconstruct the peculiar velocity field from the redshift-space distribution of dark matter halos. Through a point-to-point comparison and examination of various statistical properties, we demonstrate that, the reconstructed velocity field is in good agreement with the ground truth. The power spectra of various velocity field components, including velocity magnitude, divergence and vorticity, can be successfully recovered when $k\lesssim 1.1$ $h/\rm Mpc$ (the Nyquist frequency of the simulations) at about 80% accuracy. This approach is very promising and presents an alternative method to correct the redshift-space distortions using the measured 3D spatial information of halos. Additionally, for the reconstruction of the momentum field of halos, UNet achieves similar good results. Hence the applications in various aspects of cosmology are very broad, such as correcting redshift errors and improving measurements in the structure of the cosmic web, the kinetic Sunyaev-Zel'dovich effect, BAO reconstruction, etc., Comment: 15 pages, 13 figures, 4 tables

BJC16-A38

Mediation analysis examines the exposure-outcome association that acts through an intermediate variable. However, mediation analysis becomes challenging when data have missing values. Although methods exist to deal with missing data and mediation analysis independently, few studies have examined how to combine the approaches, specifically, how to pool the mediation analysis results across a series of imputed datasets and compute confidence intervals for target parameters. We propose a new technique that combines multiple imputation with maximum likelihood estimation. Using computer simulations, we compare the performance of our proposed approach with a traditional bootstrap approach. Our method performs well and is more computationally efficient than other resampling methods. We apply the new method to randomized trial data on the role of cadmium exposure in mediating the effects of an environmental health intervention on birth weight.

The instability of phosphine ligated copper hydride nanoclusters (CuH NCs) has largely limited their application in areas such as H2 storage, CO2 reduction, etc. In this work, the stability of CuH NCs was remarkably enhanced by improving their antioxidant capacity through two different approaches: (i) metal doping and (ii) ligand modification. Three NCs, AuCu24H22(PPh3)12, Cu25H22((p-FPh)3P)12, and AuCu24H22((p-FPh)3P)12, were controllably synthesized, and their structures were determined by single-crystal X-ray diffraction. The compositions of these NCs were further confirmed by electrospray ionization mass spectrometry and nuclear magnetic resonance. More importantly, we achieved gram-level production of M@Cu24 (M = Cu/Au) NCs protected by electron-withdrawing ligands (p-FPh)3P, which in turn proved their superior stability; such a large-scale preparation laid the foundation for future explorations of copper-rich NCs. This work hopes to shed light on large-scale generation of ultrastable Cu-based NCs.

Many applications in public clouds require a high fan-in, many-to-one type of data communication (known as TCP incast) in modern Data Center Networks (DCNs). Such communication could cause severe incast congestion in switches and result in TCP throughput collapse, substantially degrading the application performance. The root cause of throughput collapse is the Retransmission Timeouts (RTO) due to packet losses in congested switches. Tenants in public clouds can opt to use a variety of TCP versions. However, the existing solutions rely on modifications of TCP protocols and specific techniques from switches, and thus these existing solutions are not always feasible for public clouds. In this paper, we are inspired by the emerging virtualization and network softwarization technologies to develop a novel scheme called Retransmission timeout Avoidance by Packet Intelligent Discarding (RAPID) using software switches. RAPID considers the number of packets of each incast flow, buffered in the switch to selectively discard some packets, and ensures that the Fast Retransmission/Fast Recovery rather than RTO is invoked at the sender(s) in response to packet loss. Thus, the long idle period of a timeout and the throughput drop are avoided. We prove that, given a predetermined minimum switch buffer space, dedicated to the incast application, RAPID can prevent RTO in all the incast senders. We also present a low-complexity heuristic version of RAPID named RAPID-ED, which combines the principles of RAPID and early detection and is extremely easy to implement on today’s software switches. We evaluate the two proposed schemes in a data center network testbed built on NS-3 simulator. The simulation results confirm the theoretical expectation, and show that the RAPID and RAPID-ED perform very well to prevent RTO of TCP incast flows and hence the throughput collapse. Compared with other incast solutions, RAPID and RAPID-ED do not modify TCP protocols and therefore are more suitable in public clouds.

This study investigated associations between cardiometabolic diseases, frailty, and healthcare utilization and expenditure among Chinese older adults. The participants were 5204 community-dwelling adults aged at least 60 years from the China Health and Retirement Longitudinal Study. Five cardiometabolic diseases were assessed including hypertension, dyslipidemia, diabetes, cardiac diseases and stroke. Frailty status was based on five criteria: slowness, weakness, exhaustion, inactivity, and shrinking. Participants were deemed frailty if they met at least three criteria. As the number of cardiometabolic diseases increased, so did the prevalence of frailty, and the proportion of healthcare utilization, including outpatient visit and inpatient visit. Moreover, the total healthcare expenditure and the odds of catastrophic health expenditure were increased with the number of cardiometabolic disorders. After adjusting for covariates, cardiometabolic diseases were positively associated with higher odds of frailty, incurring outpatient and inpatient visit. And individuals with 2 or more cardiometabolic diseases had a higher odds of catastrophic health expenditure than persons with non-cardiometabolic disease. Participants who were frailty were more likely to report higher odds of healthcare utilization. These findings suggest that both cardiometabolic diseases and frailty assessment may improve identification of older adults likely to require costly, extensive healthcare.

We present Starduster, a supervised deep learning model that predicts the multi-wavelength SED from galaxy geometry parameters and star formation history by emulating dust radiative transfer simulations. The model is comprised of three specifically designed neural networks, which take into account the features of dust attenuation and emission. We utilise the Skirt radiative transfer simulation to produce data for the training data of neural networks. Each neural network can be trained using ~ 4000 - 5000 samples. Compared with the direct results of the Skirt simulation, our deep learning model produces ~ 0.005 mag and ~ 0.1 - 0.2 mag errors for dust attenuation and emission respectively. As an application, we fit our model to the observed SEDs of IC4225 and NGC5166. Our model can reproduce the observations, and provide reasonable measurements of the inclination angle and stellar mass. However, some predicted geometry parameters are different from an image-fitting study. Our analysis implies that including a constraint at (rest-frame) ~ 40 micron could alleviate the degeneracy in the parameter space for both IC4225 and NGC5166, leading to broadly consistent results with the image-fitting predictions. Our SED code is publicly available and can be applied to both SED-fitting and SED-modelling of galaxies from semi-analytic models., 16 pages, 9 figures. Accepted for publication in ApJ

Solid-state lithium metal batteries are one of the best candidates for the next generation of energy storage devices. However, their applications are greatly limited by low ionic conductivity at ambient temperature and poor interfacial compatibility of solid-state electrolytes. Herein, a novel composite solid-state electrolyte consisted of polyethylene oxide (PEO), aramid nanofibers (ANFs) and Li7La3Zr2O12 (LLZO) was designed and prepared. The ANFs and PEO constructed a three-dimensional flexible framework by electrostatic attraction, and LLZO particles as Li+-conducting fillers were introduced into the polymer backbone. As a result, compared to the pure PEO host, the crystallinity of prepared electrolyte was remarkably decreased, and the ionic conductivity was increased to 1.36 mS cm-1 at 30 °C. LiFePO4/Li cells with the electrolyte delivered a high specific capacity of 152 mAh g-1 and the capacity retention was over 88 % after 400 cycles, and the LiNi0.6Co0.2Mn0.2O2/Li cell can stably operate 200 cycles at 0.5C under 30 °C. During cycling, a stable solid electrolyte interphase (SEI) was formed on the surface of lithium anode, inhibiting the formation of lithium dendrite and dead lithium, and improving the cyclic stability of the battery. Furthermore, the electrolyte exhibited satisfactory mechanical properties, high thermal stability, and good interfacial compatibility and stability with the lithium metal anode. This work could provide a reference for the development and practical application of solid-state lithium metal batteries at ambient temperature.

To investigate the effect of protein kinase A (PKA) activation on aggregation funetion of platelets in vitro.The peripheral blood of healthy adults were collected, and the washed platelets were gained from collected peripheral blood. The washed platelets were treated with PKA activator Forskolin, then the platelet aggregation was induced by using Ristocetin, Thrombin, Collagen and ADP respectively, the platelet aggregation level was detected by the platelet aggregator.Compared with the controls, 5 μmol/L forskolin significantly inhibited ADP and collagen-induced platelet aggregation (P＜0.001), and showed mild inhibiting effect on Thrombin-induced platelet aggregation (P＜0.05). 2.5-10 μmol/L forskolin significantly inhibited ADP and Collagen -induced platelet aggregation (P＜0.001); but not showed significantly inhibitory effects on Ristocetin-induced platelet aggregation (P＞0.05).PKA activation inhibits agonists-induced platelet aggregation.蛋白激酶A活化对血小板聚集功能的影响.研究蛋白激酶A（Protein kinase A，PKA）对体外血小板聚集功能的影响.收集健康成年人外周血并获取洗涤血小板；采用PKA活化剂Forskolin体外处理洗涤血小板；利用瑞斯托霉素（Ristocetin），凝血酶（Thrombin），胶原（Collagen），二磷酸腺苷（ADP）诱导血小板聚集，利用血小板聚集仪检测血小板聚集情况.与对照组相比较，5 μmol/L的Forskolin可显著抑制ADP和Collagen诱导的血小板聚集（P＜0.001）；对Thrombin诱导的血小板聚集也具有一定抑制作用（P＜0.05）。而2.5-10 μmol/L的Forskolin对Ristocetin诱导的血小板聚集无明显抑制作用（P＞0.05）；对ADP和Collagen诱导的血小板聚集也具有显著抑制作用（P＜0.001）.蛋白激酶A活化能抑制血小板的聚集功能.

It is well known from the Butcher-Oemler effect that galaxies in dense environment are mostly red with little star formation and the fraction of blue galaxies in galaxy groups/clusters also declines rapidly with redshifts. A recent work by Hashimoto et al. reported a local 'blue cluster' with high fraction of blue galaxies ($\sim 0.57$), higher than the model predictions. They ascribed this blue cluster to the feeding of gas along a filamentary structure around the cluster. In this work we use group catalog from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) and the state-of-art of semi-analytic model (SAM) to investigate the formation of blue clusters in local Universe. In total, we find four blue clusters with halo mass $\sim 10^{14}M_{\odot}$ at $0.02 < z < 0.082$, while only the one found by Hashimoto et al. is in a filamentary structure. The SAM predicts that blue clusters have later formation time and most blue satellite galaxies are recently accreted. We conclude that the formation of blue clusters is mainly governed by newly accreted blue satellites, rather than the effect of large-scale environment., 11 pages, 11 figures, accepted by RAA

Quantification of the pattern and spatial distribution of soil organic carbon (SOC) is essential to comprehending many eco-hydrological processes. To obtain a better understanding of the spatial variability of SOC in a typical farming-pastoral zone, 270 soil samples were collected at 45 sampling sites from every 20 cm soil layer. Semi-variance function theory and ordinary Kriging interpolation were applied to identify the spatial variability of SOC. The results showed that SOC in the area was relatively low and decreased with depth and from the basin edge to the centre with a measured mean content of 0.07–0.65 g/kg. The strongest variability in the zone in the top soil layer (0–40 cm) was in the centre part of the zone, which was supposed to be the most concentrated area of human activities in the zone. As soil depth increase, the degree of variation of SOC decreased. Gaussian, exponential, and spherical models were suggested to successfully simulate SOC in different soil depth zones. The spatial distribution of SOC showed strong variability in the same soil depth zone, with a nugget to sill ratio of less than 14% and a range of 30–160 km.

Precast dry joints in segmental columns are important to ensure the structural integrity and continuous to transfer both shear and flexural forces. Though dry joints have the concern of durability problems, they are the trend for convenience in site construction and less climate influenced. Ten precast column joint specimens were fabricated and tested under direct shear loading. The failure patterns of solid section keyed specimens were shearing off of male shear keys and diagonal cracks in female shear keys. The failure sequence was from top to lower shear keys. But the failure pattern of hollow section specimens was flexural failure of upper male or lower female shear keys, shearing off of vertical shear keys, and diagonal cracks in vertical female shear keys. The shear force-relative slippage relations of specimens exhibited two or three stages. Higher confinement stress, solid section (or enough key cover concrete thickness), and enough number of keys were essential to maintain high shear strength and ductile responses. Two formulation methods of shear strength prediction formula were deduced. One is based on the failure envelope of uniaxial compression and tension strength of concrete, the other one is based on tension strength Mohr circle only. The proposed formula has comparable prediction precision for the joint shear test database. Shear key shear stress and shear strength contribution were analyzed with the test data. The specimen shear stress transfer and distribution were qualitatively investigated with a two dimensional FE model.

The subthalamic nucleus (STN) is an effective therapeutic target for deep brain stimulation (DBS) for Parkinson's disease (PD), and histamine levels are elevated in the basal ganglia in PD patients. However, the effect of endogenous histaminergic modulation on STN neuronal activities and the neuronal mechanism underlying STN-DBS are unknown. Here, we report that STN neuronal firing patterns are more crucial than firing rates for motor control. Histamine excited STN neurons, but paradoxically ameliorated parkinsonian motor deficits, which we attributed to regularizing firing patterns of STN neurons via the hyperpolarization-activated cyclic nucleotide-gated channel 2 (HCN2) channel coupled to the H2 receptor. Intriguingly, DBS increased histamine release in the STN and regularized STN neuronal firing patterns under parkinsonian conditions. HCN2 contributed to the DBS-induced regularization of neuronal firing patterns, suppression of excessive β oscillations, and alleviation of motor deficits in PD. The results reveal an indispensable role for regularizing STN neuronal firing patterns in amelioration of parkinsonian motor dysfunction and a functional compensation for histamine in parkinsonian basal ganglia circuitry. The findings provide insights into mechanisms of STN-DBS as well as potential therapeutic targets and STN-DBS strategies for PD.

The central neurotensin system has been implicated in reward, memory processes, also in the regulation of anxiety. However, the neural substrates where neurotensin acts to regulate anxiety have not been fully identified. The prelimbic region of medial prefrontal cortex (PrL) holds a key position in the modulation of anxiety-related behaviors and expresses neurotensin 1 receptor (NTS1). This study investigated the effects of activation or blockade of NTS1 in the PrL on anxiety-like behaviors of rats. Our results demonstrated that infusion of a selective NTS1 agonist or neurotensin into the PrL produced anxiogenic-like effects. Administration of a NTS1 antagonist into the PrL did not affect anxiety-like behaviors of normal rats, but attenuated anxiogenic effects induced by restraint stress. Moreover, we employed molecular approaches to downregulate the expression of NTS1 in the PrL, and found that downregulation of NTS1 in the PrL induced anxiolytic effects in restraint stress rats, also confirming the pharmacological results. Together, these findings suggest that NTS1 in the PrL is actively involved in the regulation of anxiety.

Following Cui et al. 2018 (hereafter Paper I) on the classification of large-scale environments (LSE) at z = 0, we push our analysis to higher redshifts and study the evolution of LSE and the baryon distributions in them. Our aim is to investigate how baryons affect the LSE as a function of redshift. In agreement with Paper I, the baryon models have negligible effect on the LSE over all investigated redshifts. We further validate the conclusion obtained in Paper I that the gas web is an unbiased tracer of total matter -- even better at high redshifts. By separating the gas mainly by temperature, we find that about 40 per cent of gas is in the so-called warm-hot intergalactic medium (WHIM). This fraction of gas mass in the WHIM decreases with redshift, especially from z = 1 (29 per cent) to z = 2.1 (10 per cent). By separating the whole WHIM gas mass into the four large-scale environments (i.e. voids, sheets, filaments, and knots), we find that about half of the WHIM gas is located in filaments. Although the total gas mass in WHIM decreases with redshift, the WHIM mass fractions in the different LSE seem unchanged., Comment: 13 pages, 8 figures, published version in MNRAS. Key results are shown in Figs. 3, 4, 8

Software-defined networking provides a promising approach to build and operate high-performance networks with high efficiency and affordable cost. While SDN is of great importance to ISPs, it is infeasible to replace the entire existing infrastructure with a clean slate of SDN design. Most early SDN practices concentrate on small-scale greenfield designs. Here, we focus on mission-critical large-scale backbone networks, and discuss the key technologies and applications for ISPs' SDN adoption. Taking an evolutionary viewpoint, we discuss strategies and approaches to integrate SDN capabilities with traditional technologies to achieve the high-performance traffic engineering, fast service provisioning, and rapid failure restoration required for existing network operations.

Intradomain traffic engineering (TE) has become an indispensable tool for Internet service providers (ISPs) to optimize network performance and utilize network resources efficiently. Various explicit routing TE methods were recently proposed and have been able to achieve high network performance. However, explicit routing has high complexity and requires large ternary content addressable memories (TCAMs) in the routers. Moreover, it is costly to deploy explicit routing in IP networks. In this paper, we present an approach, called generalized destination-based multipath routing (GDMR), to achieve the same high performance as explicit routing. The main contribution of this paper is that we prove that an arbitrary explicit routing can be converted to a loop-free destination-based routing without any performance penalty for a given traffic matrix. We present a systematic approach including a heuristic algorithm to realize GDMR. Extensive evaluation demonstrates the effectiveness and robustness of GDMR.

Mastitis is a disease that affects dairy cow health, and the timely detection of mastitis can improve the efficiency of mastitis treatment and reduce economic losses in the milk industry. To improve the detection speed and achieve automatic recognition of dairy cow mastitis, this study proposed a deep learning network EFMYOLOv3 (Enhanced Fusion MobileNetV3 You Only Look Once v3) based on the bilateral filtering enhancement of thermal images. EFMYOLOv3 is used to automatically detect dairy cow eyes and udders and is applied to the detection of mastitis in dairy cows based on thermal infrared images. We proposed a bilateral filtering image enhancement algorithm based on gray histograms to enhance image details to compensate for weak thermal image details and enhance the contrast between the foreground and background. We chose the lightweight MobileNetV3 as the backbone of YOLOv3. Based on the location attention mechanism, we used the multiscale enhanced fusion feature pyramid network structure as the feature extraction module. The feature map used for prediction was designed with the appropriate resolution and powerful multilayer semantic features to improve the accuracy of target detection. We replaced the standard convolutions in the base layer with depthwise separable convolutions to reduce the number of learning parameters. To verify the effectiveness of the target detection algorithm, the accuracy, recall, average frame rate, average accuracy and other indicators were compared with the SSD (single shot multibox detector) and YOLOv3 (You Only Look Once v3) algorithms. The test results revealed that the average frame rate of the EFMYOLOv3 algorithm is 99 frames per second (fps), and the average accuracy is 96.8%, which means that the key parts of the cow can be detected quickly and accurately. The temperature difference between the eyes and the udders was obtained by the target detection algorithm, and the mastitis detection of dairy cows was performed and compared with the somatic cell count (SCC). The results showed that the accuracy of the mastitis classification algorithm is 83.33%, and the sensitivity and specificity are 92.31% and 76.47%, respectively. This method realized accurate positioning of key parts of dairy cows and can be used for the automatic recognition of dairy cow mastitis.

A catalyst based on mixed V-Ni oxides supported on TiO

The mechanism of laser paint removal is studied based on emission spectrum and composition analysis by using laser induced breakdown spectroscopy and X-ray energy spectrum technology. The electron density and electron temperature of the plasma was calculated with the LIBS spectrums with different laser parameters. The morphologies of ablated paint surface were analyzed with a scanning electron microscopy while the changes of paint composition before and after ablation were measured with an X-ray spectrometer. The results show that, the plasma electron density, temperature and ablation area gradually increase with the increasing of incident laser energy. The carbon (C) content in paint decreases from 78.25% to 67.07% after the laser irradiation, indicating the occurrence of the ablation in the process of laser paint removal. By comparing the content of titanium (Ti) elements, C element and aluminum (Al), we found that the paint ablation will be more severe at higher laser energy. This paper is important to in-depth study of laser paint removal mechanism.

It has been shown, both in simulations and observationally, that the tidal field of a large galaxy can torque its satellites such that the major axis of satellite galaxies points towards their hosts. This so-called `shape alignment' has been observed in isolated Milky Way-like galaxies but not in `Local Group'-like pairs. In this study, we investigate the shape alignment of satellite galaxies in galaxy pairs similar to the Local Group identified in the Sloan Digital Sky Survey Data Release 13 (SDSS DR13). By stacking tens of thousands of satellite galaxies around primary galaxy pairs, we find two statistically strong alignment signals. (1) The major axes of satellite galaxies located in the (projected) area between two primaries (the {\it facing} region) tend to be perpendicular to the line connecting the satellite to its host (tangential alignment), while (2) the major axes of satellite galaxies located in regions away from the other host (the {\it away} region) tend to be aligned with the line connecting the satellite to its host (radial alignment). These alignments are confirmed at $\sim5\sigma$ levels. The alignment signal increases with increasing primary brightness, decreasing pair separation, and decreasing satellite distance. The alignment signal is also found to be stronger in filamentary environments. These findings will shed light on understanding the mechanisms of how satellite galaxies are affected by the tidal field in galaxy pairs and will be useful for investigating galaxy intrinsic alignment in the analyses of weak gravitational lensing., Comment: 12 pages, 12 figures, 1 table, MNRAS published

The nucleus accumbens (NAc), integrating information from the prefrontal cortex and limbic structures, plays a critical role in reward and emotion regulation. Previous studies have reported that the NAc shell receives direct noradrenergic projections, and activation of α

The application of chitosan/β-sodium glycerophosphate (β-GP) thermosensitive hydrogel has been limited by the relatively slow gelation, weak mechanical resistance and poor cytocompatibility. In this study, sodium hydrogen carbonate (NaHCO3) was applied with β-GP as gel agents to produce high-strength hydrogel. The hydrogels prepared with high NaHCO3 concentration or more gel agents showed shorter gelation time, better thermostability, drastically enhanced resistance in compression. Meanwhile, the hydrogels presented obvious porous structures and excellent biocompatibility to HUVEC and NIH 3T3 cultured in vitro with higher NaHCO3 concentration and moderate concentration of β-GP. Overall, appropriate concentration of β-GP combined with NaHCO3 can be a good gel regent to improve properties of chitosan thermosensitive hydrogels.

We use a sample of 83 high-resolution cosmological zoom-in simulations and a semi-analytic model (SAM) to study the stochasticity of galaxy formation in haloes ranging from dwarf to Milky Way masses. Our simulated galaxies reproduce the observed inefficiency of galaxy formation as expressed through the stellar, gas and baryonic Tully-Fisher relations. For HI velocities in the range (70 < V < 220 km/s), the scatter is just 0.08 to 0.14 dex, consistent with the observed intrinsic scatter at these scales. At low velocities (20 < V < 70 km/s), the simulated scatter is 0.2-0.25 dex, which could be tested with future observations. The scatter in the stellar mass versus dark halo velocity relation is constant for 30 < V < 180 km/s, and smaller (~0.17 dex) when using the maximum circular velocity of the dark matter only simulation, Vmax, compared to the virial velocity ($V_{200}$ or $V_{200}^{DMO}$). The scatter in stellar mass is correlated with halo concentration, and is minimized when using a circular velocity at a fixed fraction of the virial radius $\simeq 0.4 R_{200}$ or with $V_��=V_{200}^{DMO} (V_{max}^{DMO} / V_{200}^{DMO})^��$ with ��~ 0.7, consistent with constraints from halo clustering. Using the SAM we show the correlation between halo formation time and concentration is essential in order to reproduce this result. This uniformity in galaxy formation efficiency we see in our hydrodynamical simulations and a semi-analytic model proves the simplicity and self-regulating nature of galaxy formation in a ��Cold Dark Matter universe., 16 pages, 13 figures, accepted to MNRAS

As service providers have started deploying SDN in their networks, traditional IP routers are gradually upgraded to SDN enabled switches. In other words, the network will have traditional IP routers and SDN switches coexisting, and it is called a hybrid SDN network. With such a network, we take advantage of SDN and propose an approach to guarantee traffic reachability in the presence of any single link failure. By redirecting traffic on the failed link to SDN switches through pre-configured IP tunnels, the proposed approach is able to react to the failures very fast. With the help of coordination among SDN switches, we are also able to explore multiple backup paths for the failure recovery. This allows the proposed approach to avoid potential congestion in the post-recovery network by choosing proper backup paths. Simulation results show that our proposed scheme requires only a very few number of SDN switches in the hybrid SDN network to achieve fast recovery and guarantee 100% reachability from any single link failure. It also shows that the proposed approach is able to better load-balance the post-recovery network comparing to IP Fast Reroute and shortest path re-calculation.

With the widespread use of broadband access technologies and the development of high-speed Internet backbones, the requirement for high-performance metropolitan area networks (MANs) is increasing. Traditional ring- or star-based metro networks are costly to scale up to high speed and cannot recover from multiple failures, while backbone solutions are too expensive to fit into the cost-sensitive metro market. This paper proposes a virtual fully connected (VFC) architecture for metro networks to provide high-performance node-to-node all-optical transportation. The architecture emulates a fully connected network by providing optical channels between node pairs without intermediate buffering, and thus realizes single-hop transportation and avoids expensive packet routers. In addition, a scheduling algorithm is developed for medium access control and dynamic bandwidth allocation, which achieves 100% throughput and provides a fairness guarantee. Simulations show that the VFC network achieves good performance under both uniform and non-uniform loads.

Proportional fair bandwidth allocation in packet switches is a fundamental issue to provide quality of service (QoS) support in IP networks. In input-queued switches, packet-mode scheduling delivers all the segments of a packet contiguously from the input port to the output port, thus greatly simplifying the design of packet reassembly modules and yielding performance advantage over cell-mode scheduling under certain conditions [1]. One of the important issues of packet-mode scheduling is how to achieve fair bandwidth allocation among flows with different packet sizes. This paper presents an algorithm called packet-mode fair scheduling (pFS) that guarantees each flow a bandwidth proportional to its reservation regardless of the packet size distribution and the system load. Simulations show that our approach achieves good fairness as well as high throughput and low packet delay. Compared to algorithms without fairness mechanism, pFS yields significant performance improvement in terms of average packet delay when the traffic is heterogeneous. A hardware implementation is presented to show that the proposed algorithm has low complexity and the computation can be completed in a single clock cycle, which makes pFS applicable to high-speed switches.

Shared Memory (SM) switches are widely used for its high throughput, low delay and efficient use of memory. This paper compares the performance of two prominent switching schemes of SM packet switches: Cell-Based Switching (CBS) and Packet-Based Switching (PBS). Theoretical analysis is carried out to draw qualitative conclusion on the memory requirement, throughput and packet delay of the two schemes. Furthermore, simulations are carried out to get quantitative results of the performance comparison under various system load, traffic patterns, and memory sizes. Simulation results show that PBS has the advantage of shorter time delay while CBS has lower memory requirement and outperforms in throughput when the memory size is limited. The comparison can be used for tradeoff between performance and complexity in switch design.

Multi-service SDH networks support both packet- and circuit-switched traffic. Optimal design of such a network means to guarantee the circuit connections and configure a logical packet-switched topology with lowest congestion. This letter first formulates the problem as a mixed integer linear programming, which achieves optimal solution but has high computation. Then a heuristic algorithm is proposed to yield near-optimal solution efficiently. Performance of the algorithm is verified by an example.

Software-Defined Networking (SDN) enables flexible flow control by caching policy rules at OpenFlow switches. Compared with exact-match rule caching, wildcard rule caching can better preserve the flow table space at switches. However, one of the challenges for wildcard rule caching is the dependency between rules, which is generated by caching wildcard rules overlapped in field space with different priorities. Failure to handle the rule dependency may lead to wrong matching decisions for newly arrived flows, or may introduce high storage overhead in flow table memory. In this paper, we propose a wildcard rule caching system for SDN named CAching in Buckets (CAB). The main idea of CAB is to partition the field space into logical structures called buckets, and cache buckets along with all the associated rules. Through CAB, we resolve the rule dependency problem with small storage overhead. Compared to previous schemes, CAB reduces the flow setup requests by an order of magnitude, saves control bandwidth by a half, and significantly reduce average flow setup time.

In this paper we propose an algorithmic approach designed to tackle and reduce the congestion events in a Distributed Data Center (DDC). Our solution is based on virtual machines (VMs) migration and, differently from the literature, it analyzes the VMs communication patterns in order to find 'tight' clusters of VMs to be migrated.

Classical traffic engineering (TE) methods calculate the optimal routing based on a single traffic matrix. However, they are unable to handle unexpected traffic changes. Thus, it is of interest to find a good routing configuration to accommodate multiple possible traffic scenarios. There are two major approaches to achieve load balancing for multiple traffic matrices: destination-based routing and explicit routing. It has been shown that explicit routing performs better than destination-based routing for multiple traffic matrices. However, explicit routing has high complexity and requires large Ternary Content Addressable Memory (TCAM) in the routers. Thus, it is power hungry and unscalable. This paper presents an approach called hybrid routing to achieve load balancing for multiple traffic matrices with low complexity and good scalability. Our basic idea is to complement destination-based routing with a small number of explicit routing forwarding entries to take advantage of both two routing approaches. Hybrid routing greatly reduces the number of forwarding entries compared with pure explicit routing. This has great value for practice in that the scheme requires very small TCAM to implement. Hybrid routing is very suitable for implementation using SDN. A heuristic algorithm is developed to obtain the near-optimal hybrid routing configuration. Extensive evaluation demonstrates the effectiveness of hybrid routing. The results show that hybrid routing achieves near-optimal load balancing compared with pure explicit routing. In particular, hybrid routing saves at least 84.6% TCAM resources in all practical networks used in our evaluation.

Chronic myelogenous leukemia (CML) is a hematopoietic malignant disease associated with expression of a chimeric BCR-ABL gene. We recently succeeded in designing a novel allosterically controllable ribozyme, the maxizyme (Tanabe et al. Biomacromolecules 2000, 1, 108-117; Kuwabara et al. Biomacromolecules 2001, 2, 788-799), that not only specifically cleaves BCR-ABL mRNA and induces apoptosis in cultured CML cells but also shows significant inhibition against the growth of an established BV173 cell line in a mouse model (Tanabe et al. Nature 2000, 406, 473-474). As an extension of our studies, we tested the maxizyme against primary CML cells in the same mouse model. The maxizyme under the control of a tRNA(Val) promoter showed significant inhibition against the growth of the primary bone marrow cells from a Japanese patient with CML. Specifically, to examine the applicability of the maxizyme in the treatment of CML, we assessed the antitumor effect of the maxizyme in murine models of CML. Fourteen weeks after the injection of primary CML cells into a NOD-SCID mouse, the bone marrow of the mouse was filled with primary CML cells as a result of diffuse leukemia. In marked contrast, when maxizyme-expressing primary CML cells were injected, the mouse remained disease-free. These results further strengthen our earlier suggestion that the maxizyme technology might provide a useful approach to the treatment of CML.

Droplet deformation and the development of the final morphology after solvent evaporation were studied in two-phase ternary polymer/polymer/solvent mixtures in an electric field. The polymer mixtures used included polystyrene (PS) with such other polymers as poly(vinyl acetate) (PVA), poly(methyl methacrylate) (PMMA), or polybutadiene (PB) in toluene as a solvent. In a dc field, the dispersed phases were distorted into ellipsoids with their major axes either parallel (prolate ellipsoids) or perpendicular (oblate ellipsoids) to the field direction, and/or they aligned in the field direction to form pearl chains. Droplets of the dispersed phases sometimes coalesced to form columns either parallel or perpendicular to the electric field direction. Sometimes the droplets or columns broke up into smaller droplets in the dc field. The final morphology usually contained spheres or prolate or oblate ellipsoids either randomly distributed in the matrix or in the form of pearl chains or columns. It was found that th...