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This letter presents the idea of ranking critical prosumers in using a novel state-sensitivity function (SSF). The SSF is designed to work in a given nodal power injection hypercube, and thus the proposed ranking method captures the effect of injection subspace. An element-wise maximum Jacobian is obtained, that quantifies the worst-case sensitivity of each injection on each state. Results from various 33-Bus system configurations highlight the proposed method’s capability in ranking state-injection risk pairs, providing node voltage risk levels and quantifying combined risk levels in peer-to-peer dominant grids.

Space-air-ground integrated vehicular networks (SAGIVN) have been widely envisioned as a promising network architecture for sixth-generation to support the Internet of Vehicles (IoV). In SAGIVN, free-space optics (FSO)-based, high altitude platform relay-assisted low Earth orbit (LEO) satellite systems have recently attracted research efforts worldwide. Critical challenges in designing and implementing FSO-based SAGIVN include atmospheric turbulence, weather conditions, and pointing misalignment. This article offers a comprehensive cross-layer design framework of error-control protocols with rate adaptation for FSO burst transmissions in HAP-aided SAGIVN. Remarkably, we propose a design of link-layer cooperative incremental redundancy (IR) hybrid automatic repeat request (HARQ)-based sliding window mechanism. An analytical channel model for HAP-aided LEO satellite to emerging unmanned aerial vehicles FSO links is provided. At the same time, the analysis can also be applied to other kinds of vehicles. The queuing behavior induced by both the cooperative IR-HARQ protocol and the rate adaptation scheme is analyzed with a Markov model. Several performance metrics are analytically obtained, including the average round-trip frame delay, throughput, and energy efficiency. The results quantitatively demonstrate the impact of atmospheric turbulence and weather conditions on the system performance and support the optimal selection of system parameters. Additionally, the effectiveness of the proposed system is numerically confirmed. Monte Carlo simulations are also performed to validate the accuracy of theoretical derivations.

In this paper, a blockchain-enabled distributed market framework is proposed for the bi-level carbon and energy trading between coal mine integrated energy systems (CMIESs) and a virtual power plant (VPP) with network constraints. To maximize the profits of these two entities and describe their complicated interactions in the market, the bi-level trading problem is formulated as a Stackelberg game considering integrating the energy market and the “cap-and-trade” carbon market mechanism. Meanwhile, in the CMIES, energy recovery units and belt conveyors can be flexibly scheduled and the pumped hydroelectric storage in the VPP is scheduled for energy management. To tackle uncertainties from PV outputs, the joint trading, and the energy management is solved by the distributionally robust optimization (DRO) method. In addition, for participants' privacy, the alternating direction method of multipliers (ADMM) - based DRO algorithm is applied to solve the trading problem in a distributed framework. Further, the Proof-of-Authority (PoA) blockchain is deployed to develop a safe and anonymous market platform. Finally, case studies along with numerous comparison cases are conducted to verify the effectiveness of the proposed method. Simulation results indicate that the proposed method can effectively reduce the system operation cost and regional carbon emission, reduce the conservativeness and protect the privacy of each participant.

This paper proposes a bi-level peer-to-peer (P2P) multi-energy trading framework for a coupled distribution network (DN) and district heating network (DHN). At the lower level, each nodal agent represents its intra-nodal prosumers to optimize the local energy scheduling and P2P trading strategies based on the modified Nash bargaining theory, and a distributed algorithm is then adopted to enable individual agents to make their strategies autonomously only with the sharing of trading information. Once the lower-level P2P bargaining is settled, each agent is required to submit its nodal net loads and trading adjustment tolerances to the network operators. At the upper level, the network operators minimize the line power losses while satisfying network operation constraints by reconfiguring the DN and DHN as well as enforcing necessary trading adjustments from the lower-level agents when the network violations incurred by the P2P trading cannot be fully solved by network reconfiguration. Mathematically, the DN operation is modelled based on the linearized DistFlow with a set of new radiality constraints to sufficiently ensure the radial structure of the DN. The DHN operation is formulated as a quasi-linear thermal flow model independent of mass flow rate and water temperature, by which the computation complexity and limitations associated with traditional DHN formulations are addressed. Finally, a multi-energy network consisting of an IEEE 33-bus DN and a 23-node DHN is used to demonstrate the effectiveness of the proposed P2P trading framework and the efficiency of the solution algorithms.

The online small-signal stability assessment of electrical power grids is typically a challenging problem due to uncertainties and parameter variations of power system dynamics as well as the incurred high computational complexity. This paper proposes a novel theoretical framework for dynamic small-signal stability assessment of power grids by estimating the region of attraction (ROA) for operating states in real time. By analyzing the latest sampling data of power grids in a fixed time window, an up-to-date training set is constructed with the aid of converse Lyapunov function, which enables us to develop an online learning approach based on Gaussian Process (GP) to assess the stability level of power grids. As a result, an iteration algorithm is designed to update the assessment parameters by learning the input-output pairs in the training set. Theoretical analysis is conducted to ensure the existence of converse Lyapunov function for differential-algebraic system that serves to describe power system dynamics, as well as to estimate the region of attraction for operating states with a given confidence level. In particular, a practical method is proposed to leverage time series of phasor measurement unit (PMU) measurements including voltage/current magnitude, phase and frequency (i.e., PMU data) of real power grids for validating the online GP approach. Moreover, validations are taken to substantiate the proposed approach by using PMU data of real smart-grid infrastructure and IEEE test cases. The proposed assessment approach contributes to situational awareness of human operators in the control station, thereby taking proactive remedial actions prior to emergencies. Note to Practitioners—This paper was motivated by the problem of online assessment of power systems security but it also applies to other industrial control systems that have stable state trajectories. Existing approaches to security assessment of power systems generally focus on the adoption of various machine-learning algorithms by treating power grid as a “black box,” which ignores the intrinsic characteristics of power systems and thus restricts the inference performance. This paper proposes a new approach using limited sampling data and system dynamics to construct a domain of stability for power grids, which can reflect the evolution of security zones and provide more accurate predictions. In this work, we mathematically characterize the domain of stability for a practical power grid by analyzing and learning its state trajectories. Then we show how the proposed approach can be efficiently implemented online, which can timely alert human operators to abnormalities. Preliminary validations suggest that this approach is feasible and effective. In future research, we will incorporate it into an energy management system and test it in other industrial processes.

This work introduces a novel polynomial chaos expansion (PCE)-based method for uncertainty quantification (UQ) in power systems, addressing probabilistic optimal power flow problem. The proposed approach leverages upon a series of transformations to overcome two main hinders to deploying POPF in practice, i.e., the vast number of random variables (RVs) and their interdependence. The proposed Lite-PCE method requires a small set of optimal power flow samples. The most important transformation is developed based on a Clayton copula to convert substantially large dimensional input variables into a single RV for efficient computing. The transformation allows Lite-PCE to be built on a single RV and offers a significant computational benefit while working with a large number of random renewable injections. The method also handles correlated random injection variables with different types of distributions in a nonparametric fashion. The Lite-PCE method is also used to develop the concept of transmission capacity sensitivity under uncertainty using coefficients of variation. The concept and nonparametric, scalable simulations are demonstrated using various IEEE test cases, up to the 1354-Bus system with 1242 random injection variables. The UQ results illustrate the efficiency and accuracy of the method for systems of considerable size and a high number of renewable injections.

In this article, a novel convexification approach for small-signal stability constraint optimal power flow has been presented that does not rely on eigenvalue analysis. The proposed methodology is based on the sufficient condition for the small-signal stability, developed as a bilinear matrix inequality (BMI), and uses network structure-preserving differential algebraic equation modeling of the power system. The proposed formulation is based on semidefinite programming and objective penalization that has been proposed for feasible solution recovery, making the method computationally efficient for large-scale systems. A vector-norm based objective penalty function has also been proposed for feasible solution recovery while working over large and dense BMIs with matrix variables. An effectiveness study carried out on WECC 9-bus, New England 39-bus, and IEEE 118-bus test systems shows that the proposed method is capable of achieving a stable equilibrium point without inflicting a high stability-induced additional cost.

The electron transport layer/perovskite interfaces play a crucial role in facilitating efficient charge transfer and minimizing recombination losses, which are key factors for achieving high power conversion efficiency (PCE) in perovskite solar cells (PSCs). Herein, a novel ionic liquid called 2-bromo-1-ethylpyridinium tetrafluoroborate (BEPBF4) is added between tin oxide (SnO2) and perovskite layers to improve the photovoltaic performance of PSCs. The BEPBF4interface modification not only reduces the defect density, increases the crystallinity, and aligns the energy bands at the interface but also shortens the lifetime of the charge carriers, resulting in improved PCE and stability. Consequently, the device modified with BEPBF4achieved a PCE of 20.14% and retained 94% of the initial PCE without encapsulation, in contrast to the control device (18.41%), which retained only 82% of the initial PCE after 1000 h of storage at ambient conditions. In addition, the BEPBF4-PSCs exhibited significantly better thermal stability, retaining 64% of the initial PCE after 400 h of continuous thermal aging at 85 °C, compared to only 31% for the unencapsulated pristine device.

Adoptive transfer of induced regulatory T cells (iTregs) can ameliorate graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (allo-HCT). CD4+ iTregs can effectively prevent GVHD but impair the graft-versus-leukemia (GVL) effect, whereas CD8+ iTregs preserve the GVL effect but have limited efficacy in GVHD control because of their instability under inflammatory conditions. Thus, we aimed to stabilize CD8+ iTregs via treatment with vitamin C (Vit C) to improve their efficacy in controlling GVHD. We found that addition of Vit C significantly improved the stability of forkhead box P3 (Foxp3) expression in CD8+ iTregs. Moreover, Vit C–treated CD8+ iTregs exhibited high efficacy in attenuating acute and chronic GVHD. The mechanistic study revealed that addition of Vit C to CD8+ iTreg culture markedly increased DNA demethylation in the conserved noncoding sequence 2 region and, hence, maintained higher Foxp3 expression levels compared with untreated controls. In acute GVHD, Vit C–treated CD8+ iTregs were able to inhibit pathogenic T-cell expansion and differentiation while reducing thymus damage and B-cell activation in cGVHD. Importantly, in contrast to CD4+ iTregs, Vit C–treated CD8+ iTregs retained the ability to control tumor relapse. These results provide a strong rationale to use Vit C in the clinic to stabilize CD8+ iTregs for the control of GVHD and preservation of GVL after allo-HCT.

Adoptive transfer of induced regulatory T cells (iTregs) can ameliorate graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (allo-HCT). CD4+iTregs can effectively prevent GVHD but impair the graft-versus-leukemia (GVL) effect, whereas CD8+iTregs preserve the GVL effect but have limited efficacy in GVHD control because of their instability under inflammatory conditions. Thus, we aimed to stabilize CD8+iTregs via treatment with vitamin C (Vit C) to improve their efficacy in controlling GVHD. We found that addition of Vit C significantly improved the stability of forkhead box P3 (Foxp3) expression in CD8+iTregs. Moreover, Vit C–treated CD8+iTregs exhibited high efficacy in attenuating acute and chronic GVHD. The mechanistic study revealed that addition of Vit C to CD8+iTreg culture markedly increased DNA demethylation in the conserved noncoding sequence 2 region and, hence, maintained higher Foxp3 expression levels compared with untreated controls. In acute GVHD, Vit C–treated CD8+iTregs were able to inhibit pathogenic T-cell expansion and differentiation while reducing thymus damage and B-cell activation in cGVHD. Importantly, in contrast to CD4+iTregs, Vit C–treated CD8+iTregs retained the ability to control tumor relapse. These results provide a strong rationale to use Vit C in the clinic to stabilize CD8+iTregs for the control of GVHD and preservation of GVL after allo-HCT.

The convex restriction of power flow feasibility sets identifies the convex subset of power injections where a solution for power flow equations is guaranteed to exist and satisfy the operational constraints. In contrast to convex relaxations, the convex restriction provides a sufficient condition for power flow feasibility under variations in power generation and demand. In this article, we present a general framework to construct convex restrictions of an algebraic set defined by equality and inequality constraints and apply this framework to the power flow feasibility problem. The procedure results in convex quadratic constraints that provide a sufficiently large region for practical operation of the grid.

Background: Systemic bleeding due to consumption coagulopathy and thrombocytopenia resulted from activation of procoagulants from Russell's viper venom (RVV) is the leading manifestation and cause of death in Russell's viper systemic envenoming. Thrombotic occlusion of vessels is rare in cases of snakebite. Here, we report two cases of RVV systemic envenoming presenting with multiple cerebral infarctions and digital gangrenes. Case Report: A 67-year-old male presented with delirium, hemolysis and oliguria six hours after being bitten by a Russell's viper over his right hand. Multiple cerebral infarction and digital gangrene were noted in addition to acute renal failure and systemic bleeding. Specific antivenin was administrated 4 days after systemic envenoming. He recovered with neurological sequelae and loss of multiple toes. Another 52-year-old female had altered consciousness and bleeding from several organs 2 hours after snakebite. Twenty-four hours later, Russell's viper was identified and specific antivenin was used. But it was too late to restore normal vital functions due to multiple cerebral infarctions and suspected diffuse ischemia in multiple organs. The patient passed away due to multiple organ failure and recurrent septic conditions after 49 days' intensive treatment. Conclusion: Thrombotic occlusion of small and midsize vessels might occur in systemic envenoming by Formosan Russell's viper. It develops early and tends to occur in patients with atherosclerotic vessels. Venom-induced vasocontriction in atherosclerotic or damaged vessels might play a key role in the mechanism of RVV systemic toxicity., Hung D, Wu M, Deng J. Division of Toxicology, Emergency Department, Taichung Veterans General Hospital, Taichung; Division of Clinical Toxicology, Medical Department, Veterans General Hospital, Taipei, [...]

Background: Methylene blue is conventionally utilized as the main treatment of methemoglobinemia, but it may be ineffective in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. We report a case of acute substance-induced methemoglobinemia with initial good response to methylene blue despite G6PD-deficiency, but hemolytic anemia appeared later. Case Reports: A male worker suffered from acute methemoglobinemia caused by accidental dermal exposure to aniline dye. Methylene blue was given with good response initially. However, mild methemoglobinemia recurred and severe Heinz body hemolytic anemia followed 3 days after treatment. G6PD deficiency was identified, then adequate hydration and packed blood transfusion were performed with adjuvant Juvela-N (dl-[Alpha]-tocopheryl nicotinate), and he recovered uneventfully. Conclusion: We suggest that caution should be taken in using methylene blue as the antidote for acute methemoglobinemia, especially when the history of G6PD deficiency is obscure. Titrating the dose of methylene blue and starting with 0.3-0.5 mg/kg initially are recommended. Some other cellular antioxidants could be considered as a supplement treatment., Liao Y-P, Hung D-Z, Yang D-Y. Division of Toxicology, Emergency Department, Taichung Veterans General Hospital, Taichung, [...]

Background: Codeine is a lawfully permitted ingredient of anti-mid and anti-cough medicine that is readily available to the public at drug stores In Taiwan. Drug abusers often use it as a substitute for morphine while out of heroin and try to make an excuse to evade the law and say that they have only taken anti-cough syrup when morphine is detected in their urine. The purpose of this study is to try to propose criteria for codeine intake using a multiple lower dose model in normal therapeutic situations. Methods: Ten healthy volunteers each received, in two days, a total of 8 doses of cough syrup containing 4.5 mg of codeine per dose. Urine specimens were collected regularly during and in 3 days after syrup use. The urine specimens were analyzed by EIA screening test and GC-MS confirmation test. Results: Positive screen was noted during syrup use and 18-30 hour after the last dose of medication. The ratios of morphine to codeine were all less than one during syrup use and 12 hour after the last dose of syrup. Only 3.1% of the urine specimens, the ratio of the concentrations of morphine to codeine were between I and 3 when the concentrations of morphine and codeine were both very low i.e. below the cut-off values. Conclusion: The results may be used as a reference for the interpretation of urine analysis after the intake of multiple doses of anti-cough syrup with codeine. The criteria for codeine intake may be proposed as codeine concentration larger than 300 ng/mL and the ratio of morphine to codeine to be less than 3., Hsu C, Hung D, Yang D. Division of Toxicology, Emergency Department, Taichung, Taichung Veterans General Hospital, [...]

In solvent extraction processes for recovering metal ions from used nuclear fuel, as well as other industrial applications, a better understanding of the metal complex phase transfer phenomenon would greatly aid ligand design and process optimization. We have approached this challenge by utilizing the classical molecular dynamics simulations technique to gain visual appreciation of the vapor/liquid and liquid/liquid interface between tri-n-butyl phosphate (TBP) and n-dodecane with air and water. In this study, we successfully reparameterized polarizable force fields for TBP and n-dodecane that accurately reproduced several of their thermophysical properties such as density, heat of vaporization, and dipole moment. Our models were able to predict the surface and interfacial tension of different systems when compared to experimental results that were also performed by us. Through this study, we gained atomistic understanding of the behaviors of TBP and n-dodecane at the interface against air and water, useful in further computational studies of such systems. Finally, our studies indicate that the initial configuration of a simulation may have a large effect on the final result.

Graft-versus-host disease (GVHD) remains one of the major complications after allogeneic bone marrow transplantation (allo-BMT). Sirtuin-1 (Sirt-1) plays a crucial role in various biological processes including cellular senescence, metabolism, and inflammatory responses. Sirt-1 deacetylation regulates different transcription factors that are important for modulating immune responses. In the current study, we addressed the role of Sirt-1 in GVHD induction by employing Sirt-1 conditional knockout mice as well as a pharmacological Sirt-1 inhibitor. Using major histocompatibility complex (MHC)–mismatched and MHC-matched murine BMT models, we found that Sirt-1−/− T cells had a reduced ability to induce acute GVHD (aGVHD) via enhanced p53 acetylation. Sirt-1-deficient T cells also promoted induced regulatory T cell (iTreg) differentiation and inhibited interferon-γ production after allo-BMT. Sirt-1 deletion in iTregs increased Foxp3 stability and restrained iTreg conversion into pathogenic T cells. Furthermore, we found that administration with a Sirt-1 inhibitor, Ex-527, significantly improved recipient survival and clinical scores, with no signs of tumor relapse. These results indicate that Sirt-1 inhibition can attenuate GVHD while preserving the graft-versus-leukemia effect. Consistently, Sirt-1-deficient T cells also displayed a remarkably reduced ability to induce chronic GVHD (cGVHD). Mechanistic studies revealed that Sirt-1 deficiency in T cells enhanced splenic B-cell reconstitution and reduced follicular T helper cell development. Sirt-1 deficiency in T cells modulated donor B-cell responses reducing both B-cell activation and plasma cell differentiation. In addition, therapeutic Sirt-1 inhibition could both prevent cGVHD and reduce established cGVHD. In conclusion, Sirt-1 is a promising therapeutic target for the control of aGVHD and cGVHD pathogenesis and possesses high potential for clinical application.

A reparameterized molecular dynamics force field for dibutyl-phosphoric acid (HDBP) has been developed. Parameterization was done using the general Amber force field, as a starting point. The density and dipole moment of bulk phase simulations compare well to that of known experimental values, and the heat of vaporization is comparable to an estimated empirical value. All values have been optimized to within 4%. The newly optimized force field was validated against the self-diffusion coefficient, matching experimental data to within 18%, which is a significant improvement compared to the nonoptimized force field. Further, a potential of mean force study was carried out to understand the behavior of hydrogen bonds in HDBP dimers. This required the determination of hydrogen bonding criteria that captures the behavior of the HDBP dimer and is reported in this work as well.

Examples of long-range electronic conductivity are rare in biological systems. The observation of micrometer-scale electronic transport through protein wires produced by bacteria is therefore notable, providing an opportunity to study fundamental aspects of conduction through protein-based materials and natural inspiration for bioelectronics materials. Borrowing sequence and structural motifs from these conductive protein fibers, we designed self-assembling peptides that form electronically conductive nanofibers under aqueous conditions. Conductivity in these nanofibers is distinct for two reasons: first, they support electron transport over distances orders of magnitude greater than expected for proteins, and second, the conductivity is mediated entirely by amino acids lacking extended conjugation, π-stacking, or redox centers typical of existing organic and biohybrid semiconductors. Electrochemical transport measurements show that the fibers support ohmic electronic transport and a metallic-like temperature dependence of conductance in aqueous buffer. At higher solution concentrations, the peptide monomers form hydrogels, and comparisons of the structure and electronic properties of the nanofibers and gels highlight the critical roles of α-helical secondary structure and supramolecular ordering in supporting electronic conductivity in these materials. These findings suggest a structural basis for long-range electronic conduction mechanisms in peptide and protein biomaterials.

Background: Cobra snakebites have been shown to induce significant local tissue necrosis in addition to systemic neurotoxic paralysis. Owing to the notable tissue swelling, cobra snakebite is frequently misdiagnosed as habu (Trimeresurus mucrosquamatus) snakebite initially. The administration of correct and specific antivenin was typically delayed. Here, we developed an enzyme-linked immunosorbent assay (ELISA) to detect Taiwan cobra venom existed in the serum of the cobra snakebite victims. Methods: Sandwich-ELISA with horseradish-peroxidase conjugated method for detecting cobra venoms in biological samples were used and applied in a case of snakebite to confirm our clinical diagnosis. Serum samples of clinical cobra snakebite patients were collected when patients were admitted to the emergency room. Result: This established technique allowed us to detect as less as 1 ng/ml. The linear regression of standard cobra venom in the serum in concentration ranging from 1 ng/ml to 100ng/ml was well with R-value to be 0.9779. Totally, 31 serum samples of 27 recognized and suspected cobra snakebite patients were analyzed by the developed ELISA technique. The highest venom level detected was 1270ng/ml in a case 2 hours after being envenomed. The serum concentrations of the venom in the bitten patients were well correlated with the severity of local tissue destruction. Conclusions: these results indicate that ELISA method that we have developed is valuable in early diagnosis and severity assessment of Taiwan cobra snakebite., Hung D, Liau M, Lin-Shiau S. Division of Toxicology, Emergency Department, Taichung Veterans General Hospital, Taichung, [...]

Modern world has an unparalleled focus on science and technology as an energy storage device as a promising alternative sources to tackle the growing energy crisis and play an important role in economic development. Thus, new approaches and novel promising electrode materials are trying to overcome high energy density without reducing supercapacitors power density and a long lifetime stability. Accordingly, rational flower like structural control of rare earth nickelate-based composite electrodes is also important but very challenging. The role of carbon composites such as single walled carbon nanotube (SWCNT) and multi walled carbon nanotube (MWCNT) with samarium nickelate (SmNiO3) is studied. Herein, the perovskite rare earth SmNiO3, SmNiO3/MWCNT and SmNiO3/SWCNT composites are prepared as potential electrode materials by solvothermal method and never reported before as electrode for supercapacitors. An asymmetric hybrid supercapacitor (SmNiO3/SWCNT//CNT) was fabricated and presented specific capacitance, energy and power density of 170.58 F/g, 53.30 Wh/kg and 749.88 W/kg at 1 A/g. The assembled asymmetric hybrid device exhibited 79.34 % of capacitance retention and 97.52 % of coulombic efficiency even after the continuous 20,000 long cycles. These superior electrochemical properties make the hybrid microflower rare earth nickelate as a good candidate for next generation electrodes in hybrid supercapacitors.

The performance of devices from organic semiconductors is often governed by charge transfer phenomena at structurally and electronically complex interfaces, which remain challenging to access and study with excellent chemical and temporal resolution. Herein, we report the preparation and X-ray spectroscopic characterization of well-defined model organic–inorganic interfaces. We discover an unexpected trend for our systems' associated charge transfer times, and we rationalize this trend with density functional theory calculations. Our findings hold relevance for understanding interfacial charge transfer phenomena in a variety of organic, biological, and bioinspired systems.

Introduction:Early ICH expansion is associated with a higher rate of poor outcomes and death in aSAH patients, especially in limited-resource settings. This study aimed to investigate the impact of ICH expansion on the outcomes and the factors related to an ICH expansion in aSAH patients in an LMIC.Hypothesis:Understanding factors related to ICH after an aneurysmal rupture in different countries, particularly in limited-resource regions, is crucial for reducing poor outcomes and mortality.Methods:We performed a multicenter prospective cohort study of patients (≥18 years) presenting with aSAH at three central hospitals in Hanoi, Vietnam, from August 2019 to June 2021. We collected data on the demographics, baseline characteristics, management, and outcomes and compared these data between patients who had an ICH expansion (defined as ICH detected on an admission CT scan) and patients who did not. We assessed factors associated with ICH expansion on admission using logistic regression.Results:Of 415 patients, 198 (47.7%) were men, and the median age was 57.0 years (IQR: 48.0-67.0). ICH expansion accounted for 20.5% (85/415) of aSAH patients. There was a significant difference in the 90-day poor outcomes (43.5%; 37/85 and 29.1%; 96/330; p=0.011) and 90-day mortality (36.5%; 31/85 and 20.0%; 66/330; p=0.001) between patients who had ICH and patients who did not have ICH expansion. The multivariate analysis showed that systolic BP of 140 mmHg or more (OR: 2.674; 95% CI: 1.372-5.214), WFNS grades II (OR: 3.683; 95% CI: 1.250-10.858) to V (OR: 6.912; 95% CI: 2.553-18.709), and a ruptured MCA aneurysm (OR: 3.717; 95% CI: 1.848-7.477) were independent predictors of ICH expansion.Conclusions:In our study, ICH accounted for a substantial proportion of aSAH patients and contributed significantly to a high rate of poor outcomes and death. On admission, a higher systolic BP, a worse neurological status, and a ruptured MCA aneurysm were independent predictors of ICH expansion. This study indicates independent predictors of an early ICH expansion, such as a higher admission systolic BP and a worse initial neurological status, after aneurysmal ruptures that require only a clinical examination and, therefore, may be particularly valuable in resource-limited settings.

Increasing fuel costs and regulation of emissions are encouraging operators, shipbuilders and researchers to seek improvements in marine vessel efficiency. In the area of vessel electrical systems, there are increasing choices as a result of research and development over the past decade giving rise to a number of promising new technologies. Promising new battery chemistries are being developed and existing chemistries are being enhanced with nano-technology. Supercapacitors and fuel cells are now powering ferries. Permanent magnets are enabling novel motor topologies and solar panel prices are decreasing. In addition to new technologies recently commercialised for vessels, new developments in electric vehicles and grid electrical systems will be applicable to the marine environment. This article reviews emerging electrical technologies and it focusses on those with potential for improving vessel efficiency within the next decade.

Stimuli-responsive, self-assembling nanomaterials hold a great promise to revolutionize medicine and technology. However, current discovery is slow and often serendipitous. Here we report a multiscale modeling study to elucidate the pH-controlled self-assembly of nanofibers from the peptide amphiphiles, palmitoyl-I-A3E4-NH2. The coarse-grained simulations revealed the formation of random-coil based spherical micelles at strong electrostatic repulsion. However, at weak or no electrostatic repulsion, the micelles merge into a nanofiber driven by the β-sheet formation between the peptide segments. The all-atom constant pH molecular dynamics revealed a cooperative transition between random coil and β-sheet in the pH range 6–7, matching the CD data. Interestingly, although the bulk pKais more than one unit below the transition pH, consistent with the titration data, the highest pKa’s coincide with the transition pH, suggesting that the latter may be tuned by modulating the pKa’s of a few solvent-buried Glu side chains. Together, these data offer, to our best knowledge, the first multiresolution and quantitative view of the pH-dependent self-assembly of nanofibers. The novel protocols and insights gained are expected to advance the computer-aided design and discovery of pH-responsive nanomaterials.

The requirements of reduced emissions and improved fuel economy led to the introduction of direct-injection (DI) spark ignition (SI) engines. A dual-fuel injection system (DI and port fuel injection (PFI)) was also used to improve engine performance at high-speed high-load conditions. Ethanol is one of the several alternative transportation fuels considered for replacing fossil fuels such as gasoline and diesel. Ethanol offers high octane quality but with lower energy density than fossil fuels. This paper presents the combustion characteristics of a single-cylinder dual-fuel injection SI engine with the following fuelling cases: case A, gasoline for both PFI and DI; case B, gasoline PFI and ethanol DI; case C, ethanol PFI and gasoline DI. For this study, the DI fuelling portion varied from 0 per cent to 100 per cent of the total fuelling over different engine operational conditions while the engine air-to-fuel ratio remained at a constant level. It was shown in all cases that the indicated mean effective pressure (IMEP) decreases by as much as 11 per cent as the DI fuelling percentage increases, except in case B where the IMEP increases by 2 per cent at a light load. The combustion burn duration increases significantly at a light load as the DI fuelling percentage increases, but only moderately at wide-open throttle (WOT). In addition, the percentage of the ethanol in the total fuelling plays a dominant role in affecting the combustion characteristics at a light load but, at a heavy load (WOT), the DI fuelling percentage becomes an important parameter, regardless of the percentage of ethanol content in the fuel.

Battery energy storage is an essential component of a microgrid. The working temperature of the battery is an important factor as a high-temperature condition generally increases losses, reduces useful life, and can even lead to fire hazards. Hence, it is indispensable to regulate the temperature profile of the battery modules and packs properly during its operation. In view of this, a two-layer optimal control and operation scheme is proposed for a microgrid with battery energy storage. In the first layer, an optimal control model is formed to derive the optimal control policy that minimizes the control efforts, consisting of the fan speed and battery current magnitude, in order to achieve a reference value of temperature in the battery module. In the second layer, the system operator of the microgrid performs an optimal power flow to search for the optimal reference for temperature and the corresponding operating current of the battery that minimizes the operation cost of the entire microgrid system. This two-layer scheme offers a great computational benefit that allows for large-scale integration of batteries. A case study is performed on the proposed two-layer framework to illustrate its performance.

AbstractIn this paper, using the real-time navigation system, RETINA, as an example, we study the important design issues underlying the processing of location-dependent continuous queries, especially those requiring access to data describing the current status of a dynamic environment and possessing spatial properties. To reduce the probability of missing the arrival deadline associated witheach navigation request, we use a time-stamp with prediction scheme to model the traffic data and replicated dynamic directed graphs to organize the traffic data required for path searching and path calculation. Correctness of the best path calculations and scalability of the system are improved through an adaptive Push or Pull (APoP ) scheme to monitor the best path and traffic data in navigation. A prototype and simulation results demonstrate the effectiveness of the system.

Abstract Understanding the driving forces for the hepatic uptake of endogenous and exogenous substrates in isolated cells and organs is fundamental to describing the underlying hepatic physiology/pharmacology. In this study we investigated whether uptake of plasma protein-bound [3H]-palmitate across the hepatocyte wall is governed by the transmembrane electrical potential difference (PD). Uptake was studied in isolated hepatocytes and isolated perfused rat livers (IPL). Protein-binding and vasoactive properties of the different perfusates were determined using in vitro heptane/buffer partitioning studies and the multiple indicator dilution (MID) technique in the IPL, respectively. Altering hepatocyte PD by perfusate ion substitution resulted in either a substantial depolarization (-14 ± 1 mV, n = 12, mean ± S.E., substituting choline for Na+) or hyperpolarization (-46 ± 3 mV, n = 12, mean ± S.E., substituting nitrate for Cl-). Perfusate ion substitution also affected the equilibrium binding constant for the palmitate–albumin complex. IPL studies suggested that, other than with gluconate buffer, hepatic [3H]-palmitate extraction was not affected by the buffer used, implying PD was not a determinant of extraction. [3H]-Palmitate extraction was much lower (p < 0.05) when gluconate was substituted for Cl- ion. This work contrasts with that for the extraction of [3H]-alanine where hepatic extraction fraction was significantly reduced during depolarization. Changing the albumin concentration did not affect hepatocyte PD, and [3H]-palmitate clearance into isolated hepatocytes was not affected by the buffers used. MID studies with vascular and extravascular references revealed that, with the gluconate substituted buffer, the extravascular volume possibly increased the diffusional path length thus explaining reduced [3H]-palmitate extraction fraction in the IPL. (Mol Cell Biochem 270: 115–124, 2005)

Amyloid fibrils are the structural components underlying the intra- and extracellular protein deposits that are associated with a variety of human diseases, including Alzheimer’s, Parkinson’s, and the prion diseases. In this work, we examine the thermodynamics of fibril formation using our newly-developed off-lattice intermediate-resolution protein model, PRIME. The model is simple enough to allow the treatment of large multichain systems while maintaining a fairly realistic description of protein dynamics when used in conjunction with constant-temperature discontinuous molecular dynamics, a fast alternative to conventional molecular dynamics. We conduct equilibrium simulations on systems containing 96 Ac-KA14K-NH2 peptides over a wide range of temperatures and peptide concentrations using the replica-exchange method. Based on measured values of the heat capacity, radius of gyration, and percentage of peptides that form the various structures, a phase diagram in the temperature-concentration plane is constructed delineating the regions where each structure is stable. There are four distinct single-phase regions: α-helices, fibrils, nonfibrillar β-sheets, and random coils; and four two-phase regions: random coils/nonfibrillar β-sheets, random coils/fibrils, fibrils/nonfibrillar β-sheets, and α-helices/nonfibrillar β-sheets. The α-helical region is at low temperature and low concentration. The nonfibrillar β-sheet region is at intermediate temperatures and low concentrations and expands to higher temperatures as concentration is increased. The fibril region occurs at intermediate temperatures and intermediate concentrations and expands to lower as the peptide concentration is increased. The random-coil region is at high temperatures and all concentrations; this region shifts to higher temperatures as the concentration is increased.

An algorithm for computing ray/B ezier patch intersections is described from a hardware design perspective. This algorithm uses patch subdivision and other geometrical techniques to find a given maximum number of intersection points nearest to the ray origin. A pipeline-based hardware architecture is proposed, the number of pipeline stages required is verified by simulation, and the performance of a load-balanced implementation based on a state-of-the-art digital signal processor is estimated.

We used dynamic Monte Carlo simulation to investigate how changing the rate of chemical or thermal renaturation affects the folding and aggregation behavior of a system of simple, two-dimensional lattice protein molecules. Four renaturation methods were simulated: infinitely slow cooling; slow but finite cooling; quenching; and pulse renaturation. The infinitely slow cooling method, which is equivalent to dialysis or diafiltration, provides refolding yields that are relatively high and aggregates that are relatively small (mostly dimers or trimers). The slow but finite cooling method, which is equivalent to multiple-step dilution, provides refolding yields that are almost as high as those observed in the infinitely slow cooling case, but in a relatively short period of time. Quenching, which is equivalent to one-step dilution or quick quenching, is extremely slow and has low re- folding yields. A maximum appears in the refolding yield as a function of denaturant concentration in the simulation but disappears after a very long duration. Finally, the pulse renaturation method provides refolding yields that are substantially higher than those observed in the other three methods, even at high packing fractions. As in the early stages of quenching, there is a maximum in the refolding yield as a function of denaturant concentration when relatively large numbers of denatured chains are added to the refolding solution at each step. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 823–834, 2002.

This work studied the structure-hepatic disposition relationships for cationic drugs of varying lipophilicity using a single-pass, in situ rat liver preparation. The lipophilicity among the cationic drugs studied in this work is in the following order: diltiazem > propranolol > labetalol > prazosin > antipyrine > atenolol. Parameters characterizing the hepatic distribution and elimination kinetics of the drugs were estimated using the multiple indicator dilution method. The kinetic model used to describe drug transport (the "two-phase stochastic model") integrated cytoplasmic binding kinetics and belongs to the class of barrier-limited and space-distributed liver models. Hepatic extraction ratio (E) (0.30--0.92) increased with lipophilicity. The intracellular binding rate constant (k(on)) and the equilibrium amount ratios characterizing the slowly and rapidly equilibrating binding sites (K(S) and K(R)) increase with the lipophilicity of drug (k(on): 0.05--0.35 s(-1); K(S): 0.61--16.67; K(R): 0.36--0.95), whereas the intracellular unbinding rate constant (k(off)) decreases with the lipophilicity of drug (0.081--0.021 s(-1)). The partition ratio of influx (k(in)) and efflux rate constant (k(out)), k(in)/k(out), increases with increasing pK(a) value of the drug [from 1.72 for antipyrine (pK(a) = 1.45) to 9.76 for propranolol (pK(a) = 9.45)], the differences in k(in/kout) for the different drugs mainly arising from ion trapping in the mitochondria and lysosomes. The value of intrinsic elimination clearance (CL(int)), permeation clearance (CL(pT)), and permeability-surface area product (PS) all increase with the lipophilicity of drug [CL(int) (ml x min(-1) x g(-1) of liver): 10.08--67.41; CL(pT) (ml x min(-1) x g(-1) of liver): 10.80--5.35; PS (ml x min(-1) x g(-1) of liver): 14.59--90.54]. It is concluded that cationic drug kinetics in the liver can be modeled using models that integrate the presence of cytoplasmic binding, a hepatocyte barrier, and a vascular transit density function.

Organic-soluble extracts of the twigs of Aglaia oligophylla collected in Vietnam yielded four insecticidal cyclopentatetrahydrobenzofurans of the rocaglamide type including one new natural product (compound 4). Moreover, two cyclopentatetrahydrobenzopyran derivatives, belonging to the aglain and aglaforbesin types, respectively, were also isolated. The aglaforbesin derivative 6 proved likewise to be a new natural product. All isolated rocaglamide, aglain, and aglaforbesin derivatives have a characteristic methylenedioxy substituent linked to C-6 and C-7 or to C-7 and C-8, respectively. Structure elucidation of the new natural products and the determination of the absolute configuration of compound 1 by calculation of its CD spectrum with molecular dynamics simulation are described. All isolated rocaglamide derivatives exhibited strong insecticidal activity toward neonate larvae of the polyphageous pest insect Spodoptera littoralis when incorporated into an artificial diet, with LC50 values varying between 2.15 and 6.52 ppm.

The initial encounter of a microbial pathogen with the host often involves the recognition of host receptors by different kinds of bacterial adhesive organelles called pili, fimbriae, fibrillae or afimbrial adhesins. The development of over 26 of these architecturally diverse adhesive organelles in various Gram‐negative pathogens depends on periplasmic chaperones that are comprised of two immunoglobulin‐like domains. All of the chaperones possess a highly conserved sheet in domain 1 and a conserved interdomain hydrogen‐bonding network. Chaperone‐subunit complex formation depends on the anchoring of the carboxylate group of the subunit into the conserved crevice of the chaperone cleft and the subsequent positioning of the COOH terminus of subunits along the exposed edge of the conserved sheet of the chaperone. We discovered that the chaperones can be divided into two distinct subfamilies based upon conserved structural differences that occur in the conserved sheet. Interestingly, a subdivision of the chaperones based upon whether they assemble rod‐like pili or non‐pilus organelles that have an atypical morphology defines the same two subgroups. The molecular dissection of the two chaperone subfamilies and the adhesive fibers that they assemble has advanced our understanding of the development of virulence‐associated organelles in pathogenic bacteria.

The Heavy Vehicle Simulator (HVS) test results of the first experiment of the California Department of Transportation (Caltrans) Accelerated Pavement Testing Program, known as CAL/APT, are presented. The Goal 1 experiment was designed to validate the existing Caltrans pavement thickness design method for drained (containing an asphalt treated permeable base layer) and undrained (containing aggregate base only) flexible pavements. The pavement performance results include fatigue crack development, surface profile, and vertical deflections. The observed performance of the two types of structures is compared. The effects of construction compaction of the asphalt concrete, bonding between asphalt concrete lifts, the relative performance of the drained and undrained structures under the controlled HVS environment, and comparison of the observed performance and performance expected by the thickness design procedure are presented and discussed.

Plasma levels of neurotensin are increased by ingestion of fat, making this peptide a candidate for mediation of pancreatic adaptation to dietary fat. We examined the effects of doses of neurotensin on pancreatic secretion and growth to determine whether doses stimulating secretion also increased pancreatic growth and lipase content in rats. Because neurotensin inhibits gastric secretion in other species, we also measured its effects on gastric secretion and growth. In conscious rats, neurotensin (33, 100, and 300 kg kg−1subcutaneously in gelatin) produced dose-related increases in pancreatic amylase output and decreases in basal gastric secretion. Duration of acid inhibition by neurotensin was longer than stimulation of amylase secretion. Chronic administration of the same doses of neurotensin to groups of rats every 8 h for 5 days produced small but statistically significant trophic effects on the pancreas. The highest dose of neurotensin significantly increased pancreatic weight (16) and content of DNA (12), protein (17), and chymotrypsinogen (60) but did not affect amylase or lipase content. There were no effects of neurotensin on any measurement of oxyntic or pyloric gland area growth. We conclude that although neurotensin stimulates both pancreatic secretion and growth, it is not the mediator of fat-induced pancreatic adaptation.

Flexible pavements containing a thin asphalt-treated permeable base (ATPB) layer have been used in California for more than 15 years. The original philosophy upon which use of ATPB is based, the implementation of that philosophy, and observations regarding its effectiveness are examined. Laboratory tests for resilient modulus of ATPB are presented for the as-compacted state, after 3 and 10 days of soaking, and after repetitive loading in the as-compacted and saturated states. The results indicate a loss of stiffness after soaking, and failure caused by stripping and loss of cohesion between the aggregates when subjected to repetitive loading while saturated. The lab test results were used in simulations of fatigue life for pavements with and without ATPB. The results indicate that predicted pavement fatigue lives are improved when ATPB is included in the pavement structure as compared with when aggregate base alone is used, but the improvement diminishes if water damage occurs in the ATPB. Recommendations are made regarding future use of ATPB in flexible pavements.

Computer integrated manufacturing uses computer technology to integrate a manufacturing system through a man-machine interface that fills the gap between manual operation and machine processes. It is clear that a computer vision-based man-machine interface makes a fully automated system possible. The basic challenge of a vision-based interface is how to extract information from digitized images and convert it to machine-friendly “knowledge”. To extract information, then, it often end up to the problem of shape decomposition. This paper proposes an new approach in decomposing compound shapes without prior knowledge of the scene. The proposed algorithm exploits the fact that planar shapes can be completely described by contour segments, and can be decomposed at their maximum concavity into simpler objects. To reduce spurious decomposition, the decomposed segments are merged into groups by analyzing and utilizing the merging hypotheses. The algorithm calculates the linking possibility by weighting the angular differentiation between two segments. The techniques are implemented and are applied to other partial shape matching problems for clustering purposes.

Refining the notion of regularity introduced by Dickson, an integral quadratic form is said to be spinor regular if it represents all integers represented by its spinor genus. Examples of positive definite primitive integral ternary quadratic forms which have this property are presented, and it is proved that there exist only finitely many equivalence classes containing such forms.

Let abe primitively represented by the genus of a ternary quadratic lattice Ldefined over the ring of integers of an algebraic number field F. Criteria to determine whether ais primitively represented by every spinor genus in the genus of Linvolve certain subgroups θ∗(Lp, a) of the multiplicative groups of the localizations Fpof Fwith respect to the various nonarchimedean prime spots pon F. In this paper these groups θ∗(Lp, a) are determined explicitly for nondyadic and 2‐adic prime spots. Examples are given which show how this information can, in some instances, be used in combination with known results, to determine all integers primitively represented by a particular positive definite ternary quadratic form.

This study was designed to determine the extent of family problems among a clinic population of Cambodian and Vietnamese refugees, and to identify similarities and differences between the two groups. All 107 patients with adolescent children from a total clinic population of 298 were interviewed using a semistructured questionnaire, results were tabulated, and statistical methods were applied. The types of problems with children described by parents were classified into the dimensions of communication, personal behaviors, school performance, social behaviors, and antisocial behaviors. There were significantly more problems described by Vietnamese parents as compared with Cambodian parents. Vietnamese parents reported significantly more dissatisfaction with life in the United States. For both ethnic groups, parents' relationships with their adolescent children were a major source of concern and had a major impact on parents' perceptions of their own health. Yet, there were important ethnic differences between these refugee groups in how patients perceived their problems.