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By incorporating [NiFe]-hydrogenases into a proteinaceous carboxysome shell, we generate a novel biocatalyst that has improved production of clean hydrogen, oxygen tolerance, and thermostability, highlighting its great potential in biotechnological applications.

We present EFRing, an index-finger-worn ring-form device for detecting thumb-to-index-finger (T2I) microgestures through the approach of electric-field (EF) sensing. Based on the signal change induced by the T2I motions, we proposed two machine-learning-based data-processing pipelines: one for recognizing/classifying discrete T2I microgestures, and the other for tracking continuous 1D T2I movements. Our experiments on the EFRing microgesture classification showed an average within-user accuracy of 89.5% and an average cross-user accuracy of 85.2%, for 9 discrete T2I microgestures. For the continuous tracking of 1D T2I movements, our method can achieve the mean-square error of 3.5% for the generic model and 2.3% for the personalized model. Our 1D-Fitts'-Law target-selection study shows that the proposed tracking method with EFRing is intuitive and accurate for real-time usage. Lastly, we proposed and discussed the potential applications for EFRing.

Post-operative pancreatic fistula (POPF) is a common complication of pancreatic resection. Somatostatin analogues (SA) have been used as prophylaxis to reduce its incidence. The aim of this study is to appraise the current literature on the effects of SA prophylaxis on the prevention of POPF following pancreatic resection.The review of the literature was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data from studies that reported the effects of SA prophylaxis on POPF following pancreatic resection were extracted, to determine the effect of SA on POPF morbidity and mortality.A total of 15 studies, involving 2221 patients, were included. Meta-analysis revealed significant reductions in overall POPF (Odds ratio: 0.65 (95% CI 0.53-0.81, p 0.01)), clinically significant POPF (Odds ratio: 0.53 (95% CI 0.34-0.83, p 0.01)) and overall morbidity (OR: 0.69 (95% CI: 0.50-0.95, p = 0.02)) following SA prophylaxis. There is no evidence that SA prophylaxis reduces mortality (OR: 1.10 (95%CI: 0.68-1.79, p = 0.68)).SA prophylaxis following pancreatic resection reduces the incidence of POPF. However, mortality is unaffected.

This study has demonstrated the importance of cathode functional layer of solid oxide electrolysis cells for CO2 electrolysis via comparing with that of solid oxide fuel cells and varying microstructure. Reducing inactive CO2 over cathodes dominates CO2 electrolysis performance in solid oxide electrolysis cells while H2 oxidation over Ni-based anodes has less effect on solid oxide fuel cells performance. Two supporting cathodes with different functional layer microstructure are compared. The cathode with dendritic pore structure shows higher performance than that with microchannel structure in terms of gas diffusion and polarization resistance owing to the faster gas diffusion pathway. The dendritic pore structure also prevents particle sintering during densifying electrolyte film. Therefore, the microstructure of cathode functional layer plays an essential role in CO2 electrolysis.

It has been proposed that future efforts should focus on basic studies, biotechnology studies and synthetic biology studies related to algal biofuels and various high-value bioproducts for the economically viable production of algal biof uels. In recognition of diminishing fossil fuel reserves and the worsening environment, microalgal biofuel has been proposed as a renewable energy source with great potential. Algal biofuel thus became one of the hottest topics in renewable energy research in the new century, especially over the past decade. Between 2007 and 2017, research related to microalgal biofuels experienced a dramatic, three-stage development, rising, growing exponentially, and then declining rapidly due to overheating of the subject. However, biofuel-driven algal biotechnology and bioproducts research has been thriving since 2010. To clarify the gains (and pains) of the past decade and detail prospects for the future, this review summarizes the extensive scientific progress and substantial technical advances in algal biofuel over the past decade, covering basic biology, applied research, as well as the production of value-added natural products. Even after 10 years of hard work and billions of dollars in investments, its unacceptably high cost remains the ultimate bottleneck for the industrialization of algal biofuel. To maximize the total research benefits, both economically and socially, it has been proposed that future efforts should focus on basic studies to characterize oilgae, on biotechnology studies into various high-value bioproducts. Moreover, the development of synthetic biology provides new possibilities for the economically viable production of biofuels via the directional manufacture of microalgal bioproducts in algal cell factories.

High-temperature electrolysis using solid oxide electrolysis cells (SOECs) provides a promising way for the storage of renewable energy into chemical fuels. During the past, nickel-based cathode-supported thin-film electrolyte configuration was widely adopted. However, such cells suffer from the serious challenge of anode delamination at high electrolysis currents due to enormous gaseous oxygen formation at the anode-electrolyte interface with insufficient adhesion caused by low sintering temperatures for ensuring high anode porosity and cathode pulverization because of potential nickel redox reaction. Here, the authors propose, fabricate, and test asymmetric thick anode-supported SOECs with firm anode-electrolyte interface and graded anode gas diffusion channel for realizing efficient and stable electrolysis at ultrahigh currents. Such a specially structured anode allows the co-sintering of anode support and electrolyte at high temperatures to form strong interface adhesion while suppressing anode sintering. The mixed oxygen-ion and electron conducting anode with graded channel structure provides a fast oxygen release pathway, large anode surface for oxygen evolution reaction, and excellent support for depositing nanocatalysts, to further improve oxygen evolution activity. As a result, the as-prepared cells demonstrate both high performance, comparable or even higher than state-of-the-art cathode-supported SOECs, and outstanding stability at a record current density of 2.5 A cm

Compartmentalization is a ubiquitous building principle in cells, which permits segregation of biological elements and reactions. The carboxysome is a specialized bacterial organelle that encapsulates enzymes into a virus-like protein shell and plays essential roles in photosynthetic carbon fixation. The naturally designed architecture, semi-permeability, and catalytic improvement of carboxysomes have inspired rational design and engineering of new nanomaterials to incorporate desired enzymes into the protein shell for enhanced catalytic performance. Here, we build large, intact carboxysome shells (over 90 nm in diameter) in the industrial microorganism Escherichia coli by expressing a set of carboxysome protein-encoding genes. We develop strategies for enzyme activation, shell self-assembly, and cargo encapsulation to construct a robust nanoreactor that incorporates catalytically active [FeFe]-hydrogenases and functional partners within the empty shell for the production of hydrogen. We show that shell encapsulation and the internal microenvironment of the new catalyst facilitate hydrogen production of the encapsulated oxygen-sensitive hydrogenases. The study provides insights into the assembly and formation of carboxysomes and paves the way for engineering carboxysome shell-based nanoreactors to recruit specific enzymes for diverse catalytic reactions., The extreme oxygen sensitive character of hydrogenases is a longstanding issue for hydrogen production in bacteria. Here, the authors build carboxysome shells in E. coli and incorporate catalytically active hydrogenases and functional partners within the empty shell for the production of hydrogen.

Sluggish CO2 reduction on the cathodes of solid oxide electrolysis cells greatly affects electrolysis performance. However, there is no study systematically investigating the cathode functional layer (CFL), where the reduction occurs. Cathode supports equipped with fast gas diffusion channels were employed as a platform to investigate the CFL, including porosity, NiO/(Y2O3)0.08Zr0.92O2 (YSZ) ratio, and thickness. The porosity was adjusted by pore former content, and a higher porosity generated a higher electrolysis current density, while the porosity improvement is limited by the fabrication process. The three-dimensional microstructure of the CFL with different NiO/YSZ ratios was reconstructed by distance correlation functions to estimate three-phase boundary density, which can explain the optimal NiO/YSZ weight ratio of 60:40 for CO2 electrolysis. Increasing CFL thickness can provide more active sites until the optimal thickness of 35 μm. Further increasing the thickness results in gas diffusion limitation. Based on the channeled cathode supports, the CFL was optimized according to CO2 electrolysis performance.

Torque safety is one of the key elements of functional safety for future automobile development. For drive-by-wire systems that are commonly used in modern vehicles, pedal signals are critical for the vehicle supervisory controller to generate appropriate torque request to the powertrain, in order to keep the vehicle speed as desired. Problems with pedals or pedal sensors will result in incorrect torque request sent to the drivetrain, possibly resulting in torque safety problems, such as sudden unintended acceleration. This paper proposes a fault detection and isolation strategy based on structural analysis as well as fault mitigation methods for torque safety of drive-by-wire systems, with focus on pedal mechanical stiction fault and pedal sensor faults. Before the diagnostic strategy is designed, fault modeling for these two types of faults are introduced to assist the design of diagnostic tests. In addition, for pedal mechanical stiction fault, this paper introduces an effective approach to calibrate the thresholds in the fault diagnostic system in order to achieve the desired tradeoff between false alarm rate and detection delay. The detection and mitigation strategies are calibrated and validated through model-in-the-loop and hardware-in-the-loop simulations using realistic pedal profiles from the testing results of the EcoCAR2 prototype vehicle developed at the authors’ institution.

Iron stress-induced protein A (IsiA), a major chlorophyll-binding protein in the thylakoid membrane, is significantly induced under iron deficiency conditions. Using immunoblot analysis and 77 K fluorescence spectroscopy combined with sucrose gradient fractionation, we monitored dynamic changes of IsiA-containing complexes in Synechocystis sp. PCC 6803 during exposure to long-term iron deficiency. Within 3 days of exposure to iron deficiency conditions, the initially induced free IsiA proteins preferentially conjugated to PS I trimer to form IsiA(18)-PS I trimers, which serve as light energy collectors for efficiently transmitting energy to PS I. With prolonged iron deficiency, IsiA proteins assembled either into IsiA aggregates or into two other types of IsiA-PS I supercomplexes, namely IsiA-PS I high fluorescence supercomplex (IHFS) and IsiA-PS I low fluorescence supercomplex (ILFS). Further analysis revealed a role for IsiA as an energy dissipater in the IHFS and as an energy collector in the ILFS. The trimeric structure of PS I mediated by PsaL was found to be indispensable for the formation of IHFS/ILFS. Dynamic changes in IsiA-containing complexes in cyanobacteria during long-term iron deficiency may represent an adaptation to iron limitation stress for flexible light energy distribution, which balances electron transfer between PS I and PS II, thus minimizing photooxidative damage.

This paper examines a farmer&rsquo, s channel selection in a supply chain led by a retailer, considering carbon emissions and products&rsquo, deterioration. Three channels&mdash, online channels, retail channels, and dual channels&mdash, are proposed. The inventory model of perishable products and the two-stage Stackelberg game model are used to illustrate the operational process. To compare performances of the three channel structures, we further determine the critical points consisting of the profits and the carbon emissions among these channels. The results provide useful insights for supply chain members and the government. Farmers can choose a channel to optimize profit with respect to deterioration rate and product yield, but it might conflict with the aim of least carbon emissions. When the deterioration rate is high, the online channel is not a suitable choice. For the government, the carbon tax contributes to the reduction of carbon emissions, but it also leads to the loss of the farmer&rsquo, s profit. Additionally, numerical results further illustrate that, from the perspective of the government, transporting and inventory processes are two major sources of emissions, and it is essential to implement carbon tax and exploit low-carbon transportation.

High-temperature electrolysis using solid oxide electrolysis cells (SOECs) provides a promising way for the storage of renewable energy into chemical fuels. During the past, nickel-based cathode-supported thin-film electrolyte configuration was widely adopted. However, such cells suffer from the serious challenge of anode delamination at high electrolysis currents due to enormous gaseous oxygen formation at the anode-electrolyte interface with insufficient adhesion caused by low sintering temperatures for ensuring high anode porosity and cathode pulverization because of potential nickel redox reaction. Here, the authors propose, fabricate, and test asymmetric thick anode-supported SOECs with firm anode-electrolyte interface and graded anode gas diffusion channel for realizing efficient and stable electrolysis at ultrahigh currents. Such a specially structured anode allows the co-sintering of anode support and electrolyte at high temperatures to form strong interface adhesion while suppressing anode sintering. The mixed oxygen-ion and electron conducting anode with graded channel structure provides a fast oxygen release pathway, large anode surface for oxygen evolution reaction, and excellent support for depositing nanocatalysts, to further improve oxygen evolution activity. As a result, the as-prepared cells demonstrate both high performance, comparable or even higher than state-of-the-art cathode-supported SOECs, and outstanding stability at a record current density of 2.5 A cm-2 .

Nitrogen oxides (NOx) are the components of fossil flue gas that give rise to the greatest environmental concerns. This study evaluated the ability of the green algae Chlorella to acclimate to high level of NOx and the potential utilization of Chlorella strains in biological NOx removal (DeNOx) from industrial flue gases. Fifteen Chlorella strains were subject to high-level of nitrite (HN, 176.5 mmol L-1 nitrite) to simulate exposure to high NOx. These strains were subsequently divided into four groups with respect to their ability to tolerate nitrite (excellent, good, fair, and poor). One strain from each group was selected to evaluate their photosynthetic response to HN condition, and the nitrite adaptability of the four Chlorella strains were further identified by using chlorophyll fluorescence. The outcome of our experiments shows that, although high concentrations of nitrite overall negatively affect growth and photosynthesis of Chlorella strains, the degree of nitrite tolerance is a strain-specific feature. Some Chlorella strains have an appreciably higher ability to acclimate to high-level of nitrite. Acclimation is achieved through a three-step process of restrict, acclimate, and thriving. Notably, Chlorella sp. C2 was found to have a high tolerance and to rapidly acclimate to high concentrations of nitrite; it is therefore a promising candidate for microalgae-based biological NOx removal. (C) 2016 Elsevier GmbH. All rights reserved.

In electric and hybrid electric vehicles (EVs/HEVs) the electric traction drive plays an important role in producing driving torque. The motor torque request is calculated based on pedal positions from the driver and motor speed measurement from the position and speed sensor, typically the resolver. When there is a fault in the resolver that leads to inaccurate motor speed measurement, the vehicle supervisory controller may request undesired motor torque, which may lead to motor torque oscillations that could result in safety or degradation problems. This paper presents a model-based approach for diagnosing the resolver fault in the electrified vehicles, with focus on two typical types of faults, amplitude imbalance and quadrature imperfection. Before the diagnostic strategy is designed, resolver failure modes and fault propagation are analysed using a high-fidelity hybrid electric vehicle powertrain simulator. The proposed diagnostic strategy is implemented and validated through model-in-the-loop simulation, augmented by experimental data.

As an integral part of electrified powertrain, resolver is broadly used to do position and speed sensing for electric motors, subject to different types of resolver faults. This paper investigates the resolver fault propagation in electrified powertrain, with focus on the amplitude imbalance, quadrature imperfection and reference phase shift in the resolver position sensing system. The resolver fault effects in the Permanent Magnet Synchronous Machine (PMSM) drive system are first analyzed based on the mathematical model of a surface mounted PMSM with direct Field-oriented Control (FOC). Then the resolver fault propagation in the powertrain is studied in terms of two different motor operating conditions, motor torque control and motor speed control. Simulation is done in Matlab/Simulink based on the PMSM drive model and the powertrain-level simulator to verify the fault propagation analyses. The results can be used to help design the resolver fault diagnostic strategy and determine speed matching condition between engine and electric motor for mode transition control in hybrid electric vehicles.

Small regulatory RNAs (sRNAs) function as transcriptional and post-transcriptional regulators of gene expression in organisms from all domains of life. Cyanobacteria are thought to have developed a complex RNA-based regulatory mechanism. In the current study, by genome-wide analysis of differentially expressed small RNAs in Synechocystis sp. PCC 6803 under high light conditions, we discovered an asRNA (RblR) that is 113nt in length and completely complementary to its target gene rbcL, which encodes the large chain of RuBisCO, the enzyme that catalyzes carbon fixation. Further analysis of the RblR(+)/(−) mutants revealed that RblR acts as a positive regulator of rbcL under various stress conditions; Suppressing RblR adversely affects carbon assimilation and thus the yield, and those phenotypes of both the wild type and the overexpressor could be downgraded to the suppressor level by carbonate depletion, indicated a regulatory role of RblR in CO2 assimilation. In addition, a real-time expression platform in Escherichia coli was setup and which confirmed that RblR promoted the translation of the rbcL mRNA into the RbcL protein. The present study is the first report of a regulatory RNA that targets RbcL in Synechocystis sp. PCC 6803, and provides strong evidence that RblR regulates photosynthesis by positively modulating rbcL expression in Synechocystis.

Small regulatory RNAs (sRNAs) function as transcriptional and post-transcriptional regulators of gene expression in organisms from all domains of life. Cyanobacteria are thought to have developed a complex RNA-based regulatory mechanism. In the current study, by genome-wide analysis of differentially expressed small RNAs in Synechocystis sp. PCC 6803 under high light conditions, we discovered an asRNA (RblR) that is 113nt in length and completely complementary to its target gene rbcL, which encodes the large chain of RuBisCO, the enzyme that catalyzes carbon fixation. Further analysis of the RblR(+)/(−) mutants revealed that RblR acts as a positive regulator of rbcL under various stress conditions; Suppressing RblR adversely affects carbon assimilation and thus the yield, and those phenotypes of both the wild type and the overexpressor could be downgraded to the suppressor level by carbonate depletion, indicated a regulatory role of RblR in CO2 assimilation. In addition, a real-time expression platform in Escherichia coli was setup and which confirmed that RblR promoted the translation of the rbcL mRNA into the RbcL protein. The present study is the first report of a regulatory RNA that targets RbcL in Synechocystis sp. PCC 6803, and provides strong evidence that RblR regulates photosynthesis by positively modulating rbcL expression in Synechocystis.

Torque security is an important element for future automobile development such as for electric and and hybrid electric vehicles (EV/HEVs). For Drive-by-Wire systems that are commonly used in modern vehicles, pedal position signals are critical for ensuring correct calculation of torque request to the rest of the powertrain. This paper develops a model based fault diagnostic scheme for electrified vehicle powertrain torque security problems, with special focus on pedal position sensor faults. After the design of the diagnostic strategy, a fault tolerant control strategy is proposed to mitigate the effect of the faults. The torque security study is applied to a case study of a prototype vehicle developed by the OSU EcoCAR2 team. The diagnostic and fault tolerant control scheme are tested and validated through Model-in-the-Loop (MIL) and Hardware-in-the-Loop (HIL) simulations.

Processors are becoming into multicore ones. The same trend is also emerging in embedded systems. More cores on the single chip provide better concurrent of the tasks. However, the task scheduling becomes the new challenge of embedded operating system. It is still an important issue that how the tasks in multicore embedded system can be scheduled efficiently under the condition of ensuring the real-time constraint. When the number of processor cores increases continuously, such situation also relates to task scheduling for efficiency. In this paper, a novel scheduling algorithm is proposed for multicore embedded systems with the satisfied real-time condition. When the number of on-chip cores increase, this algorithm can meet the new requirements. The experimental results show that our algorithm has achieved its target.

More and more cores are integrated onto a single chip to improve the performance and reduce the power consumption of CPU without the increased frequency. The core are connected by lines and organized as a network, which is called network on chip (NOC) as the promising paradigm. NOC has improved the performance of the CPU without the increased power consumption. However, there is still a new problem that how to schedule the threads to the different cores to take full advantages of NOC. In this paper, we proposed a new multi-thread scheduling algorithm based on thread connection for NOC. The connection relationship of the threads will be analyzed and divided into different thread sets. And at the same time, the network topology of the NOC is also analyzed. The connection relationship of the cores is set in the NOC model and divided into different regions. The thread sets and core regions will be establish correspondence relationship according to the features of them. And the multi-thread scheduling algorithm will map thread sets to the corresponding core regions. In the same core set, the threads in the same set will be scheduled via different proper approaches. The experiments have showed that the proposed algorithm can improve the performance of the programs and enhance the utilization of NOC cores.