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Background. Resting-state functional magnetic resonance imaging (rs-fMRI) is a promising method for the study of brain function. Typically, rs-fMRI is performed on anesthetized animals. Although different functional connectivity (FC) in various anesthetics on whole brain have been studied, few studies have focused on different FC in the aged brain. Here, we measured FC under three commonly used anesthesia methods and analyzed data to determine if the FC in whole brain analysis were similar among groups. Methods. Twenty-four male aged Wistar rats were randomly divided into three groups (n = 8 in each group). Anesthesia was performed under either isoflurane (ISO), combined ISO + dexmedetomidine (DEX) or α-chloralose (AC) according to the groups. Data of rs-fMRI was analyzed by FC in a voxel-wise way. Differences in the FC maps between the groups were analyzed by one-way analysis of variance and post hoc two-sample t tests. Results. Compared with ISO + DEX anesthesia, ISO anesthesia caused increased FC in posterior brain and decreased FC in the middle brain of the aged rat. AC anesthesia caused global suppression as no increase in FC was observed. Conclusion. ISO could be used as a substitute for ISO + DEX in rat default mode network studies if the left temporal association cortex is not considered important.

BACKGROUND The aim of this study was to analyze the value of ocular endoscopy in detecting and extracting intraocular cilia in patients with ocular trauma. MATERIAL AND METHODS We retrospectively analyzed data on identification and extraction of 46 intraocular cilia in 16 eyes with open-globe injury during endoscope-assisted vitrectomy. RESULTS A total of the 16 patients with open-globe injury were operated on from September 2002 to June 2019. The cornea in 14 eyes was cloudy. Two eyes had endophthalmitis and 13 eyes had retinal detachment. A total of 46 cilia were extracted through direct observation under the ocular endoscope during vitrectomy 1 to 68 weeks after injury. The number of cilia per eye varied from 1 to 10. Most of the cilia were located in or near the wound. Postoperative IOP was normal in 14 patients. The follow-up after surgery showed hypotony in only 2 eyes (7.2 and 5.8 mmHg, respectively). Compared with preoperative intraocular pressure, there was a statistically significant difference. The postoperative visual acuity improved in 12 eyes and remained unchanged in 3 eyes. The vision after surgery was significantly improved compared with that before surgery (P=0.006). The intraocular pressure increased significantly after operation (P0.001). And no glaucoma or retinal detachment or endophthalmitis was found. No eyes needed additional vitreous surgery. CONCLUSIONS Ocular endoscopy allows surgeons to detect intraocular cilia that were no undetected by CT or B-ultrasound preoperatively in time and to extract them effectively. It improves performance of vitrectomy in the presence of a cloudy cornea and also prevents exogenous endophthalmitis. The vision of patients with ocular trauma was improved.

BACKGROUND Endophthalmitis, or inflammation of the internal tissues of the eye, may follow trauma and results in loss of vision if not treated promptly. Vitrectomy is used to debride the inflamed vitreous. This retrospective study aimed to compare the outcome from conventional vitrectomy (CV) and endoscope-assisted vitrectomy (EAV) performed for endophthalmitis within five days and 10 days after open ocular trauma. MATERIAL AND METHODS The clinical data from 18 patients (18 eyes) with endophthalmitis caused by open ocular trauma were analyzed at a single center. CV or EAV was performed based on the degree of vision and the involvement of the vitreous cavity. RESULTS Of the 18 patients with endophthalmitis, seven patients underwent EAV, and 11 patients underwent CV. The number of cases with preoperative corneal laceration, edema, bleeding, and formation of corneal nebular opacity was higher in the EAV group compared to the CV group. Four patients had retinal detachment, of which three patients were treated with EAV. Seventeen patients had their sight restored by a single vitrectomy procedure. In 10 cases, the culture of the vitreous fluid was positive for infection, and eight patients had Gram-positive Staphylococcus epidermidis infection. Follow-up showed that vitrectomy performed within five days (P=0.001) and 10 days (P=0.047) of open ocular trauma resulted in significant improvement of visual acuity. CONCLUSIONS Vitrectomy for endophthalmitis due to open ocular trauma performed within five days of injury restored visual acuity. EAV was shown to be an effective alternative to CV.

BACKGROUND This study aimed to investigate the effect of cobalt transporter II gene (rs1801198, rs2301957, rs9606756) polymorphism on serum homocysteine level and its correlation with young and middle recurrent cerebral infarction. METHODS A total of 348 young and middle-aged patients with cerebral infarction admitted to The Third Affiliated Hospital of Qiqihar Medical University from January 2017 to March 2018 were enrolled. The patients were divided into recurrent and non-recurrent groups according to follow-up. DNA was extracted from the peripheral blood of patients, and the DNA samples were genotyped by IlluminaBeadArray technology to detect the gene polymorphisms of cobalt transporter II (TCN2) sites (rs1801198, rs2301957, rs9606756), and the homocysteine (hcy) level was determined by cyclic enzymatic method. VitB12 and folate levels were measured by chemiluminescence immunoassay, and holo transcobalamin (holoTC) expression levels were detected by enzyme-linked immunosorbent assay. RESULTS The frequency of alleles of rs9606756 mutation in the recurrent group was higher than that in the non-recurrent group (P

Background: During vitrectomy, a relatively high level of accuracy is required when using retinal laser energy, which is difficult to control in the presence of subretinal fluid and other conditions. We explored the clinical effects of retinal pigment epithelium (RPE)photocoagulation in closing retinal breaks and preventing hypotony during vitrectomy. We describe the possible indications of RPE photocoagulation. Methods: This was a prospective, non-random, uncontrolled case series study. We recruited 20 patients, with retinal detachment in 20 eyes. In this study, RPE photocoagulation was performed under the detached retina and retinal holes. RPE laser photocoagulation was performed in 3-4 rows at the edge of the periphery around the hole and the tear, replacing the traditional retinal photocoagulation and closing part or all of the retinal break. The energy of RPE photocoagulation was 100-150mJ for 120-200ms to seal the breaks, and the same energy but little gaps for the RPE without covering of retina. Results: After vitrectomy, in 19 eyes, there was a visible pigmentation reaction around the hole and tear, except for 1 eye the retinal hole located in the myelinated nerve fibre area. The mean best-corrected visual acuity (BCVA) at 6 months after surgery was significantly higher than that before surgery (p=0.002). At the last follow-up, the mean BCVA remained significantly higher than that before surgery (p=0.001).There was no significant difference in BCVA between the 6th month and the last follow-up (p=0.806).The thickness of the neurosensory layer in RPE photocoagulation and retinal photocoagulation area at 1 month after surgery was 216.33±54.42μm and 87.67±34.65μm, respectively. By the end of the follow-up, there were no serious complications, and the retinas of all 20 eyes were reattached. No hypotony occurred after surgery. Conclusions: The effects of RPE photocoagulation and retinal photocoagulation are similar in closing retinal breaks. The RPE laser sealed the retinal breaks and did not damage the neurosensory layer, but still caused pigmentation formation on the RPE, resulting in adhesion between the neurosensory layer and the RPE layer. Laser photocoagulation could be considered as comparable to glue instead of welding when closing the retinal breaks. Trial registration ChiCTR1900021504,2019-02-24.

Protective effect of edaravone on blood-brain barrier (BBB) in experimental cerebral infarction rats was investigated. SD rats were prepared as the permanent middle cerebral artery occlusion model and randomly divided into 4 groups: cerebral infarction model group, edaravone low, medium and high dose groups. Healthy rats only for operation and no filament were selected as the sham operation control group. Rats in the cerebral infarction model group and the control group were given normal saline, and those in the edaravone low, medium and high dose groups were given edaravone 10, 15 and 20 mg/kg, respectively. The survival status, the body weight and neurological function score before and after treatment, the brain water content and the permeability of the blood-brain barrier after treatment were measured. The expression levels of NFE2-related factor 2 (NRF2) and hemeoxygenase 1 (HO-1) in rat brain tissue were detected by western blotting. Levels of peripheral blood malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) were detected by ELISA. The state of the rats in three edaravone groups was improved compared with that of the cerebral infarction group. Compared with the cerebral infarction model group, the body weight was significantly increased after treatment and the neurological function score, brain tissue water content and BBB permeability were significantly decreased in three edaravone groups (P

In the IP-over-WDM networks, electric power is more consumed at IP layer. This letter proposes two power-saving dynamic connection provision algorithms, called Most Used First (MUF) and State Transmission Time Aware (STTA) respectively, which can direct the incoming connection request to already provisioned router line cards and chassis, and hence reduce the number of active IP devices so to save electric power. For a typical network, MUF and STTA can save over 3% and 7% power respectively comparing with conventional power-unaware approach.

Image segmentation is an important research subject in the area of image processing. Most of the existing image segmentation methods partition the image based on the single cue of the image, the color, which brings a serious limitation when the complex scenes involve in the natural images. In this paper, we introduce a novel unsupervised image segmentation method via affinity propagation which takes into local texture and color features with superpixel map. The new method fuses color and texture information as local feature of each superpixel. The experimental results show that the proposed method performs better and steadier when partitioning various complex nature images, comparing to the existing methods.

The challenges imposed by environmental issues, such as global warming and the energy crisis, are demanding more responsible energy usage, including in the optical networking field. In optical transmission networks, most of the electrical power is consumed by the optical-electrical-optical conversion in optical repeaters. Modern optical network control plane technologies allow idle optical repeaters to be put into a low-power sleep mode. Inspired by this, we propose a novel power-efficient routing and wavelength assignment (RWA) algorithm, called HTAPE. The HTAPE algorithm exploits the knowledge of the connection holding times to minimize the number of optical repeaters in the active mode, and hence reduce the total electricity consumption of the optical network. We test the new algorithm on the typical CERNET and USNET networks. Compared with traditional RWA algorithms without holding-time-awareness, it is observed that the HTAPE algorithm yields significant reductions in power consumption. © 2012 Science China Press and Springer-Verlag Berlin Heidelberg.

Survivability has been widely recognized as an important design issue for optical networks. In practice, as the network scale keeps expanding, this design problem becomes more critical. Due to scalability and domain privacy, designing the protection scheme in multi-domain networks is more difficult than that in single domain networks. The path computation element (PCE) is known as an efficient architecture to compute optimal traffic engineering (TE) paths in multi-domain multilayer networks. Based on the PCE architecture, we first propose a new dynamic domain-sequencing scheme that considers the load balance of inter-domain links and then propose an improved segment-shared protection approach called DDSP. It can provide 100% protection ability for multiple failures that each single domain has only one failed link. Finally, the protection based on the optimal dynamic domain-sequencing scheme, called OPT, is designed, to evaluate performance of our algorithm and to provide the good bounding for the dynamic domain-sequencing scheme with limited intra TE information. Simulation evaluation shows that the proposed scheme is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost. Furthermore, the performance of it is near to OPT.

Aims We investigated the protective effects of chemical stimulation of cerebellar fastigial nucleus (FN) on stress gastric mucosal injury (SGMI) and its possible neuro-regulatory mechanisms in rats. Main methods Chemical stimulation, electrical stimulation, chemical ablation, electrolytic lesion, and microinjection were used to investigate the effects of FN simulation on SGMI. The model of SGMI was established by restraint and water (21 ± 1 °C)-immersion (RWI) for 3 h in rats. The gastric mucosal injury index indicated the severity of gastric mucosal injuries. Key findings We showed that microinjection of L-glutamic acid into the FN or electrical stimulation of the FN markedly attenuated SGMI. Either chemical lesion of the FN or electrical ablation of the decussation of superior cerebellar peduncle (DSCP) obviously aggravated SGMI. The protective effect of FN stimulation on SGMI was reversed after chemical ablation of the lateral hypothalamic area (LHA). The protective effect of FN was prevented by pretreatment with the glutamic acid decarboxylase antagonist, 3-MPA into the FN or GABAA receptor antagonist, bicuculline into the LHA. The protective effect of FN was abolished by pretreatment with sympathectomy. The discharge frequency of greater splanchnic nerve (GSN) was decreased and gastric mucosal blood flow (GMBF) was increased after chemical stimulation of FN. These results indicate that the FN participates in regulation of SGMI, and is a specific area in the CNS for exerting protective effects on the SGMI. The DSCP, LHA and peripheral sympathetic nerve may be involved in this process. Significance Our findings might provide a new and improved understanding of the cerebellar function and an effective treatment strategy for stress gastric mucosal injury.

Survivability for multi-domain optical networks is becoming a key parameter due to expanding network. In order to provide the shared-path-protected lightpath in multi-domain optical mesh networks, we propose a protection solution, called GSLSSP. A new source egress gateway selecting mechanism is adopted in this solution. For each connection request, this mechanism can enable the source node to select a better egress gateway node to the destination domain and compute one inter-domain working path near the optimal path with the cooperating of this gateway node, under scalability and domain privacy constraint of multi-domain networks. And then one intra-domain link-disjoint local segment-backup path for each working-segment path is computed out in each single-domain passed by the working path. Simulation evaluation shows that the proposed scheme can provide 100% protection ability for multiple failures. Besides, it is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost than other schemes.

Aims To investigate the protective effects of 17β-estradiol postconditioning against ischemia/reperfusion (I–R)-induced gastric mucosal injury in rats. Main methods The animal model of gastric ischemia/reperfusion was established by clamping of the celiac artery for 30 min and reperfusion for 30 min, 1 h, 3 h, 6 h, 12 h or 24 h. 17β-estradiol at doses of 5, 50 or 100 μg/kg (rat) was administered via peripheral veins 2 min before reperfusion. In a subgroup of rats, the estrogen receptor antagonist fulvestrant (Ful, 2 mg/kg) was intravenously injected prior to 17β-estradiol administration. Histological and immunohistochemical methods were employed to assess the gastric mucosal injury index and gastric mucosal cell apoptosis and proliferation. The malondialdehyde (MDA) concentration, superoxide dismutase (SOD) activity, xanthine oxidase (XOD) activity and hydroxyl free radical (–OH) inhibitory ability were determined by colorimetric assays. Subsequently, the expression of Bcl-2 and Bax in rat gastric mucosa was examined by western blotting. Key findings 17β-estradiol dose-dependently inhibited gastric I–R (GI–R) injury, and 17β-estradiol (50 μg/kg) markedly attenuated GI–R injury 1 h after reperfusion. 17β-estradiol inhibited gastric mucosal cell apoptosis and promoted gastric mucosal cell proliferation in addition to increasing SOD activity and –OH inhibitory ability and decreasing the MDA content and XOD activity. The Bax protein level increased 1 h after GI–R and was markedly reduced by intravenous administration of 17β-estradiol. In contrast, the level of Bcl-2 protein decreased 1 h after GI–R and was restored to normal levels by intravenous administration of 17β-estradiol. These effects of 17β-estradiol were inhibited by pretreatment with fulvestrant. Significance 17β-estradiol postconditioning should be investigated further as a possible strategy against gastric mucosal injury.

A probe-fed stacked square microstrip antenna for dual-band circularly polarized (CP) applications is presented. By properly selecting two square patches in the proposed design and loading a chip-resistance along the centerline of each square patch, dual-band CP radiation with small frequency ratio can be achieved. In order to prevent the second operating frequency from shifting to higher band which is resulted from a small air-gap between two substrates, an additional patch is introduced. Compared with conventional stacked dual-band CP antennas, the proposed antenna can achieve a smaller frequency ratio and has a larger tolerance of processing as well. Details of the proposed antenna design and experimental results for the dual-band CP performances are presented and discussed.

A new broadband circularly polarized (CP) square slot antenna with coplanar waveguide fed is proposed. Two symmetrical E-shaped slits embedded in opposite corners of ground plane are designed to obtain an excellent CP bandwidth. Simulated results show that the broadband performance is formed by three resonant modes. Some key parameters are studied to analysis the characteristics of the proposed antenna. Measured results show that the 3 dB axial ratio bandwidth is larger than 32.8% relative to the center frequency of 2165 MHz and the impedance bandwidth is as large as 54.8% with voltage standing wave ratio (VSWR) ≤2. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 409–412, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24904

As wireless devices become more pervasive, mobile ad hoc networks are gaining importance, motivating the development of highly scalable ad hoc networking techniques. In this paper, we give an overview of the Safari architecture for highly scalable ad hoc network routing, and we present the design and evaluation of a specific realization of the Safari architecture, which we call Masai. We focus in this work on the scalability of learning and maintaining the routing state necessary for a large ad hoc network. The Safari architecture provides scalable ad hoc network routing, the seamless integration of infrastructure networks when and where they are available, and the support of self-organizing, decentralized network applications. Safari's architecture is based on (1) a self-organizing network hierarchy that recursively groups participating nodes into an adaptive, locality-based hierarchy of cells; (2) a routing protocol that uses a hybrid of proactive and reactive routing information in the cells and scales to much larger numbers of nodes than previous ad hoc network routing protocols; and (3) a distributed hash table grounded in the network hierarchy, which supports decentralized network services on top of Safari. We evaluate the Masai realization of the Safari architecture through analysis and simulations, under varying network sizes, fraction of mobile nodes, and offered traffic loads. Compared to both the DSR and the L+ routing protocols, our results show that the Masai realization of the Safari architecture is significantly more scalable, with much higher packet delivery ratio and lower overhead.

Simulation and physical implementation are both valuable tools in evaluating ad hoc network routing protocols, but neither alone is sufficient. In this paper, we present the design and performance of PRAN, a new system for the physical implementation of ad hoc network routing protocols that unifies these two types of evaluation methodologies. PRAN (physical realization of ad hoc networks) allows existing simulation models of ad hoc network routing protocols to be used - without modification - to create a physical implementation of the same protocol. We have evaluated the simplicity and portability of our approach across multiple protocols and multiple operating systems through example implementations in PRAN of the DSR and AODV routing protocols in FreeBSD and Linux using the standard existing, unmodified ns-2 simulation model of each. We illustrate the ability of the resulting protocol implementations to handle real, demanding applications by describing a demonstration with this DSR implementation transmitting real-time video streams over a multihop mobile ad hoc network; the demonstration features mobile robots being remotely operated based on the real-time video stream transmitted from the robot over the network. We also present a detailed performance evaluation of PRAN to show the feasibility of our architecture

A failure in optical networks can cause tremendous loss in data and revenue. To guarantee the service availability and handle network failures, shared protection is commonly used. One promising shared protection approach has been proposed which introduce relative priorities among connections contending for access to the shared backup paths. In this paper, a novel priority-aware shared protection algorithm is developed, called FPS, for the dynamic connection provision. In FPS, the relative priority between an incoming connection and an existing connection is flexibly determined to maximize the usage of backup wavelengths after ensuring not to violate the SLA-defined availability requirement of the existing connection. We show that the FPS can obtain significant improvements on resource overbuilding ration and blocking probability compared with existing priority-aware shared protection algorithm.

Simulation and analytical models for the ultrasonic/sonic drill/corer (USDC) are described in this paper. The USDC was developed as a tool for in-situ rock sampling and analysis in support of the NASA planetary exploration program. The USDC uses a novel drive mechanism, which transfers ultrasonic vibrations of a piezoelectric actuator into larger oscillations of a free-flying mass (free-mass). The free-mass impact on the drill bit creates a stress pulse at the drill tip/rock interface causing fracture in the rock. The main parts of the device (transducer, free-mass, bit, and rock) and the interactions between them were analyzed and numerically modeled to explore the drive mechanism. Each of these interactions is normally described by a time-dependent 2- or 3-D model involving slowly converging solutions, which makes the conventional approach unsuitable for USDC optimization studies. A simplified integrated model using tabulated data was developed to simulate the operation of the USDC on desktop PC and successfully predicted the characteristics of the device under a variety of conditions. The simulated results of the model and the experimental data used to verify the model are presented.

We present algorithms for planning dynamically feasible backward paths and controlling unmanned surface vehicles along such paths using a nonlinear backstepping trajectory tracking controller. These algorithms have been developed for Virginia Tech's riverine unmanned surface vehicle (USV). The USV is a rigid hull inflatable boat with a servo-actuated outboard motor. The backward path planning algorithm uses the receding horizon approach and solves an optimal control problem by converting it into a nonlinear programming (NLP) problem. The control law is a modification of the forward nonlinear backstepping control law, augmented to compensate for the bistable sternward behavior exhibited by the riverine USV. Specifically, the bistable sternward behavior is modeled as two linear, stable left and right turnrate regions separated by an unstable zero turnrate region. Experimental results indicate that this backstepping controller adequately compensates for model and environmental disturbances.

Based on the path computation element (PCE) architecture, we propose an export policy constrained segment-shared protection approach called EPCSSP. Under dynamic traffic with different load, the performances results show that EPCSSP not only can completely protect double-link failures but also can make the tradeoffs between the resource utilization ratio, blocking ratio, and protection-switching time.

Traditional contention-based random-access wireless MAC protocols such as IEEE 802.11 DCF are designed for single-hop wireless networks and do not perform well in multi-hop scenarios due to inefficiency in their medium reservation mechanisms. In this paper, we introduce a new MAC protocol, called EMAC, which improves the efficiency of wireless medium reservation for general asynchronous multi-hop wireless networks. By exploiting limited routing information at the MAC layer, EMAC enables multiple asynchronous stations along a delivery path to cooperate in their random medium access. In particular, a control frame can travel across a multi-hop path composed of asynchronous nodes, and make synchronized medium reservations for an upcoming data frame transmission. This distributed cooperation at the MAC layer can greatly improve the medium reservation efficiency by reducing intra-flow contentions. Simulation results show that EMAC can improve end-to-end throughput compared to IEEE 802.11 DCF in chain scenarios by up to 85% and can avoid throughput starvation in cross scenarios.

A compact single-feed stacked microstrip patch antenna for tri-band circularly polarized (CP) application is presented. The proposed antenna with two properly square patches. By inserting two pairs of narrow slots parallel to the edges of the top square patch, with two protruding slots perpendicular to the edge, the top patch can perform CNSS dual-frequency (1.61 GHz and 2.49 GHz) CP radiations using a single probe feed. The GPS frequency (1.57 GHz) is achieved by cutting a slit in the bottom square patch and by adjusting the length of the slit, the antenna can perform CP radiation. Details of the proposed antenna design and results for the obtained tri-band CP performances are presented and discussed.

The global warming and the energy crisis require an energy saving information communication network, including in the optical networking. Recently, network nodes are becoming more modular, which provides more flexible power management. In this work, we consider modular node architecture and first introduce power-saving in the OADM port assignment problem. A power-efficient port assignment approach, called STA, is proposed which exploits the knowledge of lightpath holding time to improve the performance of power-saving. We conduct simulation experiments on 14-node NSF network, and observe that significant power saving is achieved by employing our algorithm comparing to other holding-time-unaware algorithms.

A compact single-feed dual-band circularly polarized (CP) patch antenna with small frequency ratio is presented. The proposed antenna consists of a circular patch and a narrow annular-ring, which resonate at 1.70 GHz and 1.57 GHz for respectively. The annular-ring was involved to obtain dual band characteristic. The CP operation is achieved by an unequal cross-slot embedded in the circular patch. Simulated and measured results are presented and discussed.

The use of asynchronous duty-cycling in wireless sensor network MAC protocols is common, since it can greatly reduce energy consumption and requires no clock synchronization. However, existing systems using asynchronous duty-cycling do not efficiently support broadcast-based communication that may be used, for example, in route discovery or in network-wide queries or information dissemination. In this paper, we present the design and evaluation of ADB (Asynchronous Duty-cycle Broadcasting), a new protocol for efficient multihop broadcast in wireless sensor networks using asynchronous duty-cycling. ADB differs from traditional multihop broadcast protocols that operate above the MAC layer, in that it is integrated with the MAC layer to exploit information only available at this layer. Rather than treating the data transmission from a node to all of its neighbors as the basic unit of progress for the multihop broadcast, ADB dynamically optimizes the broadcast at the level of transmission to each individual neighbor of a node, as the neighbors asynchronously wakeup. We evaluate ADB both through ns-2 simulations and through measurements in a testbed of MICAz motes using TinyOS, and compare its performance to multihop broadcast based on X-MAC and on RI-MAC. In both evaluations, ADB substantially reduced energy consumption, network load, and delivery latency compared to other protocols, while achieving over 99% delivery ratio.

This paper presents a methodology for short-term load forecasting using a semigroup-based system-type neural network. A technique referred to as algebraic decomposition is proposed for the neural network architecture, where the network is decomposed into a semigroup channel and a function channel. The semigroup channel, made of coefficient vector, is shown to exhibit the dependency of the load on temperature, and the function channel extracts the basis vector to represent the fundamental characteristics of daily load cycles. Regression and rearrangement methods are applied to handle the roughness of the load data surface, and interpolation and extrapolation of coefficient vector is achieved based upon the hourly temperature. The recombination of basis vector and coefficient vector at each hour gives the load forecast. This methodology is verified by testing on the load data from New England Independent System Operator (ISO) and achieves satisfactory results.

Background No published study has addressed the effect of genistein postconditioning on gastric ischemia–reperfusion (GI–R) injury in rats. Aim To examine whether capsaicin receptor-mediated genistein postconditioning protects against gastric ischemia–reperfusion injury via the PI3K/Akt signal pathway. Methods and Results Chloraldurat-anesthetized rats underwent occlusion of the celiac artery for 30 min, followed by 60 min of reperfusion. Based on this animal model of gastric ischemia–reperfusion injury, genistein at doses of 100, 500 or 1,000 lg/kg was administered via peripheral vein 5 min before reperfusion. The dose of 500 lg/kg was optimal for postconditioning, at which the severity of I–R-induced gastric injury significantly decreased. Immunohistochemistry also showed that gastric mucosal cell apoptosis decreased. Capsazepine (CPZ), a specific antagonist for the capsaicin receptor, was administered (1,000 lg/kg, i.v.) just before ischemia. Capsaicin (50 mg/kg, s.c.) once a day for 4 days reversed the protective effects of genistein. Reverse transcriptionpolymerase chain reaction (RT-PCR) and Western blotting showed increased calcitonin gene-related peptide (CGRP) expression in genistein group but not in capsazepine or capsaicin group. CGRP inhibitor CGRP8-37 also prevented the effects of genistein in decreasing gastric mucosal injury index. In addition, PI3K inhibitor LY294002 (1.5 mg/kg) reversed the protective effect of genistein. Compared with genistein group, Western blots also demonstrated decreased Akt phosphorylation in LY294002 group. Conclusion Our data suggest that capsaicin receptors mediated the protective effects of genistein postconditioning. CGRP secreted by activated capsaicin-sensitive neurons played an important role in the protective effects of genistein. PI3K/Akt pathway was also involved in the protective effects of genistein.

This study was aimed at the relationship model between LMX and work performance. Hypotheses mode was set up, and Chinese edition of LMX scale, team cohesion scale and team performance evaluation scale were used in this paper. 342 survey questionnaires were sent and 231 valid accounting for 67% of the total were received, the samples came from many industries, such as finance, energy, scientific research, IT and telecommunications, representing the state-owned, joint ventures, and private enterprises. Then, multiply stepwise regression, intermediary effect and regulatory effect analysis are used. Through those studies, we found that LMX had significantly positive effects on work performance and the team type and team cohesion affected the relationship between LMX and work performance as regulation variable and intermediary variable respectively. The follows also be found that in order to achieve performance targets, managers should strengthen exchange and communication with staff, care for members’ feeling and special needs, show their care and support and build harmony subordinate relationship to promote team cohesion and work performance with good LMX.

Bandwidth-on-Demand (BoD) services are characteristic of dynamic bandwidth provisioning based on customers' resource requirement, which will be a must for future networks. BoD services become possible with the development of make-before-break, Virtual Concatenation (VCAT) and Link Capacity Adjustment Scheme (LCAS). In this paper, we introduce BoD services into L1VPN, thus the resource assigned to a L1VPN can be gracefully adjusted at various bandwidth granularities based on customers' requirement. And we propose a dynamic bandwidth adjustment scheme, which is compromise between make-before-break and VCAT&LCAS and mainly based on the latter. The scheme minimizes the number of distinct paths to support a connection between a source-destination pair, and uses make-beforebreak technology for re-optimization.

Generalized Multi-Protocol Label Switching (GMPLS) appears as a promising candidate to implement the control plane for next-generation optical networks. In GMPLS-based wavelength division multiplexing (WDM) optical networks, existing resource reservation protocol (RSVP) may fail to setup a multicast Label Switched Path (LSP) with high probability, since multiple destinations in one multicast session may reserve different wavelengths and result in reservation collision at branch nodes. In this work, we extend the existing GMPLS RSVP signaling protocol and propose an efficient scheme to set up optical multicast LSP and avoid wavelength resources collision, called Last-hop Label Set (LLS) scheme, by introducing a new object called Last-hop Label Set object in Resv message. Once the setup of a multicast LSP fails caused by wavelength reservation collision at a branch node, the branch node can re-reserves a new wavelength according to the Last-hop Label Set object within Resv messages. The numerical results indicate that the proposed LLS scheme offers lower blocking probability compared to the existing GMPLS signaling scheme.

Layer 1 VPN (L1VPN) extends the notion of VPN to the optical domain to provide virtually dedicated circuit like leased lines, so that the security is more enhanced. Despite their secure gains from channel isolation, VPNs still suffer fragilities resulting from link-failures or node-failures. Extensive activities on survivability designs for wavelength-routed optical networks are proposed, including various protection and restoration schemes, but concerns on network edge are rare. Dual-homing is an effective skill to achieve survivability gains for L1VPNs. There are two dual-homing mode: Active/Standby mode and Load-Sharing mode In this paper, we investigate the problem of PE assignment, which is the key of dual-homing design and is NP-hard. We formulate it as an integer programming problem, and propose heuristic solutions. Simulation results show that the proposed solutions work in a correct and effective way and the Load-Sharing mode has higher bandwidth efficiency than Active/Standby mode.

A ring based optical virtual private network (OVPN) employing contention sensing and avoidance is proposed to deliver multiple-to-multiple group-multicast traffic. The network architecture is presented and its operation principles as well as performance are investigated. The main contribution of this article is the presentation of an innovative group-multicast capable OVPN architecture with technologies available today.

Duty cycling is a widely used mechanism in wireless sensor networks (WSNs) to reduce energy consumption due to idle listening, but this mechanism also introduces additional latency in packet delivery. Several schemes have been proposed to mitigate this latency, but they are mainly optimized for light traffic loads. A WSN, however, could often experience bursty and high traffic loads, such as due to broadcast or convergecast traffic. In this paper, we present a new MAC protocol, called Demand Wakeup MAC (DW-MAC), that introduces a new low-overhead scheduling algorithm that allows nodes to wake up on demand during the Sleep period of an operational cycle and ensures that data transmissions do not collide at their intended receivers. This demand wakeup adaptively increases effective channel capacity during an operational cycle as traffic load increases, allowing DW-MAC to achieve low delivery latency under a wide range of traffic loads including both unicast and broadcast traffic. We compare DW-MAC with S-MAC (with and without adaptive listening) and with RMAC using ns-2 and show that DW-MAC outperforms these protocols, with increasing benefits as traffic load increases. For example, under high unicast traffic load, DW-MAC reduces delivery latency by 70% compared to S-MAC and RMAC, and uses only 50% of the energy consumed with S-MAC with adaptive listening. Under broadcast traffic, DW-MAC reduces latency by more than 50% on average while maintaining higher energy efficiency.

Duty-cycle MAC protocols have been proposed to meet the demanding energy requirements of wireless sensor networks. Although existing duty-cycle MAC protocols such as S-MAC are power efficient, they introduce significant end-to-end delivery latency and provide poor traffic contention handling. In this paper, we present a new duty-cycle MAC protocol, called RMAC (the routing enhanced MAC protocol), that exploits cross-layer routing information in order to avoid these problems without sacrificing energy efficiency. In RMAC, a setup control frame can travel across multiple hops and schedule the upcoming data packet delivery along that route. Each intermediate relaying node for the data packet along these hops sleeps and intelligently wakes up at a scheduled time, so that its upstream node can send the data packet to it and it can immediately forward the data packet to its downstream node. When wireless medium contention occurs, RMAC moves contention traffic away from the busy area by delivering data packets over multiple hops in a single cycle, helping to reduce the contention in the area quickly. Our simulation results in ns-2 show that RMAC achieves significant improvement in end-to-end delivery latency over S-MAC and can handle traffic contention much more efficiently than S-MAC, without sacrificing energy efficiency or network throughput.

Rock, soil, and ice penetration by coring, drilling or abrading is of great importance to a large number of space and earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet. An Ultrasonic/Sonic Drill/Corer (USDC) has been developed as an adaptable tool for many of these applications [Bar-Cohen et al., 2001]. The USDC uses a novel drive mechanism to transform the ultrasonic or sonic vibrations of the tip of a horn into a sonic hammering of a drill bit through an intermediate free-flying mass. The USDC design was modified to fabricate an Ultrasonic/Sonic Ice Gopher that is designed to core down to meters depth for in situ analysis and sample collection. This technology was demonstrated at Lake Vida in the Dry Valleys, Antarctica. Coring ice at -20°C as in Lake Vida has been a challenge and efforts were made to develop the required ice core cutting, ice chip handling and potential ice melting (and refreezing) during drilling. The analysis and fabrication challenges and testing results are presented in this paper.

Environment protection requires more testing and analysis tools. To detect buried chemical containers or other objects embedded in soil and avoid possible damage to them, a penetrator was developed for packed soil that requires low penetration force (the force needed to push rod probe into the soil). The design was based on the novel mechanism used by the ultrasonic/sonic driller/corer (USDC) that was developed jointly by scientists at the NDEAA lab at JPL and engineers at Cybersonics, Inc. [Bar-Cohen et al 2001, Bao et al 2003]. In the penetrator, a small free-flying mass is energized by a piezoelectric transducer and impacts a rod probe on its shoulder at frequencies of several hundred Hetz. The impacts help the probe to penetrate the packed soil with low pushing force. A large reduction of the penetration force was achieved. Preliminary tests show that the effects of the penetrator on plastic containers and other objectors are minimal. The details of the design of the prototype penetrator and the results of performance tests are presented.

Summary form only given. Recent advances in technology have made low-cost, low-power wireless sensors a reality. A network of such nodes can coordinate among themselves for distributed sensing and processing of certain phenomena. We propose an architecture to provide a stateless solution in sensor networks for efficient addressing and routing. We name our architecture TreeCast. We propose a unique method of address allocation, building up multiple disjoint trees which are geographically inter-twined and rooted at the data sink. Using these trees, routing messages to and from the sink node without maintaining any routing state in the sensor nodes is possible. Next, we use this address allocation method for scoped addressing, through which sensor nodes of a particular type or in a particular region can be targeted. Evaluation of our protocol using ns-2 simulations shows how well our addressing and routing schemes perform.

An ultrasonic/sonic driller/corer (USDC) was developed to address the challenges to the NASA objective of planetary in-situ rock sampling and analysis. The USDC uses a novel drive mechanism, transferring ultrasonic vibration into impacts on a drill stem at sonic frequency using a free-flying mass block (free-mass). The main parts of the device and the interactions between them were analyzed and numerically modeled to understand the drive mechanism and allow design of effective drilling mechanism. A computer program was developed to simulate the operation of the USDC and successfully predicted the characteristic behavior of the new device. This paper covers the theory, the analytical models and the algorithms that were developed and the predicted results.

Future NASA exploration missions are increasingly seeking to conduct sampling, in-situ analysis and possibly return samples to Earth for further tests. Missions to Mars are the more near term projects that are seeking such capabilities. One of the major limitations of sampling on Mars and other low gravity environments is the need for high axial force when using conventional drilling. To address this limitation an ultrasonic/sonic drilling/coring (USDC) mechanism has been developed that employs an ultrasonic horn driven by a piezoelectric stack. The horn drives a free mass that resonates between the horn and drill stem. Tests have shown that the USDC addresses some of the key challenges to the NASA sampling objectives. The USDC is lightweight (450 g), requires low preload (< 5N) and can be driven at lower power (5W). The device has been shown to drill rocks with various levels of hardness including granite, diorite, basalt and limestone. The hammering action involved with the coring process can produce cores of various shapes, which need not necessarily be round. Because it is driven by piezoelectric ceramics, the USDC is highly tolerant to changes in its operating environment. These actuation materials can be designed to operate at a wide range of temperatures including those expected on Mars and Venus. Although the drill is driven electrically at 20 kHz, a substantial sub-harmonic acoustic component is found that is crucial to drilling performance. An analytical model has been developed to explain this low frequency coupling in the horn, free mass, drill stem and rock.

Transparent optical network (TON) is now rapidly booming to be popular, and a threat of an all-optical crosstalk attack with high power will emerge. In this paper, the penalty of crosstalk attack propagation, including intrachannel crosstalk inside the optical cross-connects, as well as direct and indirect interchannel crosstalk within fibers, is evaluated. Our work has proved that these crosstalk attacks do propagate in the TON but with limited propagation stages, which will be useful for the planning, management, and design of TON.