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The thermal properties, microstructure, and mechanical properties of Fe-18Mn-3Ti (wt%) were investigated, focusing on the effects of different heat-treatment processes. Results revealed that the 450 °C warm-rolling sample (450 WR) exhibited promising mechanical properties. Specifically, this sample displayed a yield strength of 988 MPa, an ultimate tensile strength of 1052 MPa, and total elongation of 15.49%. Consequently, a favorable strength-ductility balance was achieved. The strain-hardening ability surpassed that of the cold rolling sample (CR). Microstructure analysis indicated the simultaneous occurrence of dynamic equilibrium between grain deformation and re-crystallization because of the co-influence of thermal and strain in the warm rolling process. This desirable mechanical property was attributed to the presence of a multi-phase (α-martensite, austenite, and ε-martensite) and heterogeneous microstructure. The improvement of ultimate tensile strength was based on grain refinement, grain co-deformation, and the transformation-induced plasticity (TRIP) effect in the early stage of plastic deformation (stage Ⅰ). The improvement of ultimate elongation (TEL) was ascribed to the TRIP effect in the middle stage of plastic deformation (stage Ⅱ). [ABSTRACT FROM AUTHOR]

Ferroelectric ceramic capacitors show great potential in pulse power devices for their fast charging-discharging characteristics and immense power density. As a relaxation ferroelectric material, Sr0.7Bi0.2TiO3 has the advantage of high energy storage efficiency. Nevertheless, its low breakdown strength limits its energy storage performance. Herein, Sr0.7Bi0.2Ti(1–1.25x)TaxO3 (SBT-T) ceramics were synthesized by introducing Ta2O5 with a broad bandgap. On the one hand, the B-site ion disorder enhanced the relaxor behavior of the SBT-T ceramics. On the other hand, the introduction of Ta boosted the impedance and activation energy of the SBT-T ceramics, thus significantly improving their breakdown strength. With the increase in Ta content, the critical electric fields of SBT-T ceramics were monotonically increased from 240 to 370 kV/cm (increased by 54%), and splendid Wrec = 2.33 J/cm3 and high η = 91.76% were achieved when x = 0.04 under 290 kV/cm. Additionally, the SBT-0.04T ceramics demonstrated excellent pulse charge–discharge speed (t0.9 of 81.69 ns) and power density (PD of 153.39 MW/cm3). This research revealed that Ta doping was an effective approach to strengthening breakdown strength, which might provide ideas for improving the energy storage performance of dielectric capacitors. [ABSTRACT FROM AUTHOR]

Protonic ceramic fuel cells (PCFCs) are attractive next-generation fuel cells working at intermediate temperature (450–700 °C). Currently, the most common method to produce PCFCs is based on co-sintering anode-supported half cells composed of thin BaZr 0.8 Y 0.2 O 3-δ (BZY20) electrolyte layers and thick NiO anode substrates. However, the BZY20 electrolyte reacts with NiO at the high temperature during co-sintering (1400–1600 °C), leading to significant loss of dopants in the electrolyte and thereby degradation in the conductivity. With the aim to improve the chemical compatibility between the BaZrO 3 -based electrolyte and NiO, in this work, we annealed the mixture of NiO and BaZrO 3 doped with different dopants, and found that good compatibility was obtained between NiO and BaZr 0.8 Yb 0.2 O 3-δ or BaZr 0.8 Tm 0.2 O 3-δ at 1500 °C, and NiO and BaZr 0.8 Yb 0.2 O 3-δ at 1350 °C. Furthermore, BaZr 0.8 Y 0.1 Yb 0.1 O 3-δ and BaZr 0.8 Y 0.12 Yb 0.08 O 3-δ also showed good chemical compatibility with NiO at 1350 and 1500 °C. Then, the half cells using the BaZrO 3 electrolyte doped with Y and Yb were fabricated, and the ionic conductivities of the electrolytes implemented into the co-sintered half cells were measured directly in wet hydrogen. The results revealed that BaZr 0.8 Y x Yb 0.2- x O 3-δ (x = 0.10, 0.12, 0.13) showed higher conductivity than that of BaZr 0.8 Y 0.2 O 3-δ , and BaZr 0.8 Y 0.1 Yb 0.1 O 3-δ exhibited the highest conductivity among the three Y and Yb co-doped samples studied in this work. [Display omitted] •Improved phase compatibility with NiO by doping BaZrO 3 with Yb or Tm. • Total doping level in BaZrO 3 keeps at 0.2 by co-doping Y and Yb without dopant loss. • Higher ionic conductivity of BaZrO 3 co-doped with Y and Yb in co-sintered cells. [ABSTRACT FROM AUTHOR]

Proline serves as an important osmolyte in maintaining osmotic pressure and stabilizing cellular structure in aquatic organisms, and is essential for adaptation to salinity stress. This study focuses on the razor clam (Sinonovacula constricta), and investigated the metabolism and synthesis of proline in response to changing salinity. The proline content in gill tissues of razor clams significantly increased over time and with different levels of salinity exposure. The key genes involved in proline metabolism, including (Aminotransferase (ScOAT), Δ1-pyrroline-5-carboxylic acid synthase (ScP5CS), and proline dehydrogenase (ScProDH) were investigated, as well as enzyme activities associated with these genes in razor clams. The expression and activity of P5CS increased significantly under hypersalinity conditions, whereas that of OAT enzyme activity decreased. This suggested that the glutamate pathway had an important role in the proline synthesis during hypersalinity. ProDH activity was negatively correlated with salinity and regulated by the proline content, indicating a significant role of ProDH in proline accumulation under hypersalinity conditions. ScP5CS was heterologously expressed in yeast Saccharomyces cerevisiae , followed by exogenous proline supplementation studies. Recombinant S. cerevisiae incubated with ScP5CS exhibited elevated levels of proline, with the growth performance of recombinant strain surpassing that of the control group after salinity stress. In addition, razor clams exposed to exogenous proline under high salinity conditions showed expedite osmotic regulation, whereby the hemolymph pressure reached equilibrium more quickly. Together, these results indicated that the proline content increased under high salinity, which could improve the tolerance of razor clams to hypersalinity, offering novel perspectives into molecular mechanism of salinity adaptation in shellfish. • Hypersalinity stress induced accumulation of proline in razor clam. • Proline synthesis primarily relied on the glutamate synthesis pathway under hypersalinity. • The accumulation of proline can improve the salinity tolerance of razor clam. [ABSTRACT FROM AUTHOR]

Solid oxide electrolysis cells (SOECs) are regarded as promising candidates for the next generation of energy conversion device due to their extremely high conversion efficiency. However, the electrolysis current density should be further increased to meet the demands of large‐scale industrial application in the future. Here, a novel anode configuration for SOEC is reported that achieves an ultra‐high current density of 5.73 A cm−2 for at least 4 h. To the best of the authors' knowledge, such current density surpasses the record of present state‐of‐the‐art research. The unique stability under such high current density is attributed to the novel SOEC constructed with a La0.6Sr0.4CoO3−δ anode catalyst nano‐layer to promote oxygen generation, vertically aligned micro channel anode scaffold to accelerate oxygen release, and integrated anode–electrolyte interface to improve the interfacial strength. The novel SOEC successfully demonstrates stable steam electrolysis under an ultra‐high current density of 5.96 A cm−2 at 800 °C under the constant operating voltage of 1.3 V, corresponding to a hydrogen production rate of 2.5 L h−1 cm−2. [ABSTRACT FROM AUTHOR]

In this article, an electrolyte flow rate control approach is developed for an all-vanadium redox flow battery (VRB) system based on the linear parameter varying (LPV) framework. The electrolyte flow rate is regulated to provide a trade-off between stack voltage efficiency and pumping energy losses, so as to achieve an energy efficient battery operation. The nonlinear process model is embedded in a linear parameter varying state–space description and a set of state feedback controllers are designed to handle fluctuations in current during both charging and discharging. Simulation studies have been conducted under different operating conditions to demonstrate the performance of the proposed approach. This control approach was further implemented on a laboratory scale VRB system. • A novel electrolyte flow rate control approach is developed for vanadium redox batteries (VRB). • The nonlinear battery system model is embedded into a Linear Parameter Varying (LPV) description. • A computationally efficient controller is designed to optimise the operational efficiency. • The proposed control design is successfully implemented on a lab-scale VRB system. [ABSTRACT FROM AUTHOR]

Mg B 2 superconducting material has a wide range of application prospects for its high transition temperature, favorable structural characteristics and low cost. When using Mg B 2 to produce superconducting energy storage magnets, it is necessary to twist superconducting wires into cables to increase their current carrying capacity. One typical cable is made of 6 Mg B 2 superconducting wires wrapped around 1 central copper wire, forming a (6+1) structure. Mg B 2 coils used for energy storage require solid impregnation and can be cooled by liquid hydrogen or solid nitrogen. Due to the need for fast charging and discharging of energy storage coils and low thermal conductivity of commonly used epoxy resin impregnation and solid nitrogen, it is necessary to consider the temperature variation characteristics caused by AC loss and eddy current loss during operation process. A coil with 8 turns in each layer and 4 layers is simulated using the (6+1)-structure cable. In order to obtain better temperature distribution results while reducing the time required for simulation operation, the simulation time is set to 1 s. The impact of epoxy resin properties and surrounding environments on the coil are then analyzed. The results indicate that increasing the thermal conductivity of epoxy resin can significantly reduce the maximum temperature of the coil, while only changing the cooling method is unhelpful in dealing with the problem of local overheating of the coil. • Epoxy resin affects the position with the highest temperature in a coil. • Cooling effects of static liquid hydrogen and solid nitrogen are almost the same. • Flow rate of liquid hydrogen is not helpful in avoiding coil overheating. [ABSTRACT FROM AUTHOR]

A novel method combining direct ink writing (DIW) and pressureless infiltration is proposed for fabricating 3D-SiC/Al composites. Chopped carbon fiber was added to DIW ink to serve as a pore-forming agent and facilitate pyrolysis to provide infiltration channels during the preoxidation process. The effects of SiC particle size and carbon fiber content on mechanical properties and the infiltration process were investigated. The thickness of the oxide films produced at different preoxidation temperatures was studied using a transmission electron microscope. The interfacial and interpenetrating phase compositions of 3D-SiC/Al were examined using scanning electron microscopy, an energy dispersive spectrometer, and X-ray diffraction. The results showed that carbon fiber can improve the infiltration effect, with SiO 2 layers of differing thickness affecting the infiltration process to different degrees. The final sample exhibited good mechanical properties with a bending strength of 330.3 MPa. [ABSTRACT FROM AUTHOR]

Fuel cells can efficiently convert the chemical energy in fuels like hydrogen and methane into electricity and are an important component for the forthcoming hydrogen society. Compared with conventional solid oxide fuel cells (SOFCs) and proton exchange membrane fuel cells (PEMFCs), protonic ceramic fuel cells (PCFCs) using proton conducting solid oxides as the electrolyte operate at intermediate temperature (400–700 °C), enabling the reduction in cost by using inexpensive catalysts and structural materials. In the last couple of decades, the development of electrolyte and electrode materials for PCFCs has seen significant advances, including fabrication of large‐size cells, promoting PCFCs to step out of the lab toward real applications. This review provides a historic overview of the development of proton conducting oxides, summarizes recent progress on the development of electrolyte and electrode materials and large‐size cells, and discusses present problems and challenges ahead. [ABSTRACT FROM AUTHOR]

Background: Drug discovery and development is the extremely costly and time-consuming process of identifying new molecules that can interact with a biomarker target to interrupt the disease pathway of interest. In addition to binding the target, a drug candidate needs to satisfy multiple properties affecting absorption, distribution, metabolism, excretion, and toxicity (ADMET). Artificial intelligence approaches provide an opportunity to improve each step of the drug discovery and development process, in which the first question faced by us is how a molecule can be informatively represented such that the in-silico solutions are optimized. Results: This study introduces a novel hybrid SMILES-fragment tokenization method, coupled with two pre-training strategies, utilizing a Transformer-based model. We investigate the efficacy of hybrid tokenization in improving the performance of ADMET prediction tasks. Our approach leverages MTL-BERT, an encoder-only Transformer model that achieves state-of-the-art ADMET predictions, and contrasts the standard SMILES tokenization with our hybrid method across a spectrum of fragment library cutoffs. Conclusion: The findings reveal that while an excess of fragments can impede performance, using hybrid tokenization with high frequency fragments enhances results beyond the base SMILES tokenization. This advancement underscores the potential of integrating fragment- and character-level molecular features within the training of Transformer models for ADMET property prediction. [ABSTRACT FROM AUTHOR]

• DEM-FEM co-simulation was adopted to analyze a separation system. • Impact of operation parameters and scraps shape on separation distance was studied. • Numerical simulations are capable to accurately describe the separation systems. End-of-life vehicles (ELVs) provide a particularly potent source of non-ferrous metal scraps. At presents, conveyor belt and air-jet nozzle are widely used in the existing separation system for non-ferrous metal scraps. Parameters such as shape of the scraps, conveyor belt speed (v), nozzle air pressure (P) and nozzle angle (α) have a significant influences on the separating accuracy and efficiency. To investigate the interaction between these parameters and their influences on the separation distance, a coupled simulation model of (Discrete Element Method) DEM and (Finite Element Method) FEM was employed to simulate the motion of the scraps and the separation process, the trajectory of the scraps under different circumstances was recorded and analyzed, the simulation model was verified using a separation platform. The results indicated that block shaped scraps have the largest separation distance followed by rod and slice shaped scraps. The separation distance of rod and slice shaped scraps increases when each of the three parameters increases, and the speed of conveyor belt (v) plays a dominant role. For blocks shaped scraps, when nozzle pressure is high, the separation distance increase with the increase of conveyor belt speed, when nozzle pressure is low, the separation distance decrease with the increase of conveyor belt speed. The nozzle pressure (P) was found to have the most noticeable impact on separation distance for block shaped scraps. For the platform in this study, the optimal operation parameters obtained were v = 1.9 m/s, P = 0.53 MPa, and α = 42°. [ABSTRACT FROM AUTHOR]

Background: Drug design is a challenging and important task that requires the generation of novel and effective molecules that can bind to specific protein targets. Artificial intelligence algorithms have recently showed promising potential to expedite the drug design process. However, existing methods adopt multi-objective approaches which limits the number of objectives. Results: In this paper, we expand this thread of research from the many-objective perspective, by proposing a novel framework that integrates a latent Transformer-based model for molecular generation, with a drug design system that incorporates absorption, distribution, metabolism, excretion, and toxicity prediction, molecular docking, and many-objective metaheuristics. We compared the performance of two latent Transformer models (ReLSO and FragNet) on a molecular generation task and show that ReLSO outperforms FragNet in terms of reconstruction and latent space organization. We then explored six different many-objective metaheuristics based on evolutionary algorithms and particle swarm optimization on a drug design task involving potential drug candidates to human lysophosphatidic acid receptor 1, a cancer-related protein target. Conclusion: We show that multi-objective evolutionary algorithm based on dominance and decomposition performs the best in terms of finding molecules that satisfy many objectives, such as high binding affinity and low toxicity, and high drug-likeness. Our framework demonstrates the potential of combining Transformers and many-objective computational intelligence for drug design. [ABSTRACT FROM AUTHOR]

WuXiBody is a bispecific antibody (bsAb) platform developed by WuXi Biologics. Its key feature is the replacement of one parental antibody's CH1/CL region with the T-cell receptor (TCR) constant domain, which prevents mispairing between non-cognate heavy chain and light chain. In addition, heavy chain heterodimerization in asymmetric WuXiBody molecule is promoted by the knobs-into-holes (KiH) technology. Despite the great success of KiH strategy in improving heterodimer formation, homodimers (especially the hole-hole homodimer) can still be generated at low levels. In general, detection and monitoring of homodimers during KiH bsAb purification are challenging as homodimers share similar physicochemical properties with the target heterodimeric bsAb. Nevertheless, the unique design of WuXiBody allows homodimers to be effectively detected and monitored by multiple methods. In the current work, with an asymmetric WuXiBody case study, we demonstrated that hole-hole homodimer can be effectively monitored by six chromatography methods including hydrophobic interaction chromatography (HIC), reverse phase (RP), cation exchange (CEX), KappaSelect, CaptureSelect CH1-XL and Protein L. • During KiH bsAb purification, homodimers are difficult to be monitored as they share similar properties with the bsAb. • WuXiBody is a bsAb platform developed by WuXi Biologics. • The unique design of WuXiBody allows homodimers to be effectively detected and monitored by multiple methods. • In a case study, HH homodimer was effectively monitored by HIC, RP, CEX, KappaSelect, CaptureSelect CH1-XL and Protein L. [ABSTRACT FROM AUTHOR]

Highlights • Investigated the feasibility of using VRB for power quality control applications. • Studied the voltage and current responses of VRB through experimental studies. • An equivalent circuit model was developed to describe the VRB transient behaviour. • The results suggest that the VRB can handle high frequency power fluctuations. • The results and proposed model are useful for battery electrical interface design. Abstract This paper studies the feasibility of using the vanadium redox flow battery (VRB) for power quality control applications. This work investigates the dynamic voltage and current responses of the VRB to load changes over a range of frequencies (up to 5 kHz), through experimental studies on a laboratory scale testing system. Experiments were carried out under different operating conditions to examine the effects of system SOC, discharging current and temperature. The analysis shows that the magnitude of battery impedance is higher at low frequencies but lower at high frequencies. These results suggest that the VRB has the ability to handle charging-discharging power fluctuations in a frequency range up to a kHz level. By using the concept of fractional order systems, the transient behaviour of the VRB cell was modelled as an equivalent circuit that utilises a constant phase element to represent the electrochemical double layer and a Warburg element to describe the effect of concentration polarisation. This equivalent circuit model is useful for electrical interface design and power flow control applications. [ABSTRACT FROM AUTHOR]

Abstract Bispecific antibodies (bsAbs) are antibodies that can simultaneously bind two distinct targets or epitopes. Their dual-targeting capacity offers expanded therapeutic potential. Currently there is a strong interest in design and production of bsAbs to achieve improved efficacy through novel mechanisms of action. However, due to the co-expression of up to four distinct polypeptide chains or assembly involving chains with extended length (in the appended IgG format), recombinant production of IgG-like bsAbs is often accompanied with increased level of product-related impurities (byproducts and aggregates) resulting from heavy chain homodimerization, heavy chain-light chain mispairing, unbalanced expression of different chains and intermolecular misassociation. As some of the byproducts display close similarity to the target bsAb, their removal poses significant challenges to the downstream processing. This article reviews methods that can effectively remove product-related impurities in IgG-like bsAb purification. Highlights • Approaches that enforce heavy chain heterodimerization and cognate heavy/light chain pairing in bsAb assembly are introduced. • Sequence engineering that can facilitate bsAb purification is briefly discussed. • Methods that can effectively remove commonly found product-related impurities in IgG-like bsAb purification are reviewed. • General suggestions on reducing the type and amount of bsAb specific byproducts are proposed. [ABSTRACT FROM AUTHOR]

Abstract Ferroniobium topologically close-packed (TCP) phase inclusions were found in the nickel-based152 nickel-based cladding of dissimilar metal weld joint in pressurized water nuclear reactor. A systematical investigation on the morphologies, microstructures and mechanical properties was conducted by using multi-scale techniques. The formation causes of the TCP-phase inclusion and its possible influences on crack initiation and propagation during long-term operation are also discussed. The ferroniobium TCP-phase inclusions originate from large-size ferroniobium supplement particles in 152 welding electrode flux during welding. The inclusion with core has a homogeneous kernel and a continuous transition zone between the core and eutectic zone, and the transition zone consists of columnar grain zone and isometric grain zone. The inclusion core is confirmed as single-phase rhombohedral Fe 7 Nb 6 (μ phase), and columnar grain zone in the transition zone is also mainly Fe 7 Nb 6 , while the isometric grain zone and the Nb-rich phase in the eutectic zone are both mainly hexagonal Fe 2 Nb (Laves phase), the other phase in the eutectic zone is austenite. The Fe 2 Nb is formed by eutectic metallurgical reaction between inclusion core and 152 cladding. The average hardness of inclusion core (17.89 GPa) is over 4.5 times as high as cladding matrix (3.91 GPa). The TCP-phase inclusion is of higher cracking susceptibility than 152 cladding, and acts as the initiation of brittle cracks during in-situ tensile test. The ferroniobium TCP-phase inclusions are of higher cracking susceptibility than 152 cladding. Graphical abstract Image 1 Highlights • The TCP-phase inclusions originate from large-size ferroniobium supplements in 152 welding electrode flux. • The TCP-phase inclusion consists of Fe 7 Nb 6 (μ phase) and Fe 2 Nb (Laves phase). • The average hardness of inclusion core (Fe 7 Nb 6 , 17.89 GPa) is over 4.5 times as high as 152 cladding matrix (3.91 GPa). • The ferroniobium TCP-phase inclusions are of higher cracking susceptibility than 152 cladding. [ABSTRACT FROM AUTHOR]

Abstract When diagnosed at an advanced stage, most cancer patients suffer from treatment failure, recurrences and low survival. Taking advantage of high-throughput sequencing and deep learning techniques, we developed an early cancer monitoring method based on multi-modal deep Boltzmann machine to (1) learn association between matched germline and somatic mutations captured by whole exome sequencing from available samples of cancer patients, and (2) predict patient-specific high-risk genes whose somatic mutations are required to drive normal tissues to a tumor state. Our experiments on a set of breast cancer samples show that our method significantly outperforms the currently used frequency-based method in the personalized prediction of genes carrying critical mutations. [ABSTRACT FROM AUTHOR]

Abstract Caprylic acid (CA), a naturally occurring eight-carbon fatty acid, has long been used as albumin stabilizer, non-IgG fraction precipitant and bactericidal agent in pharmaceutical industry. The mechanisms through which CA achieves its effects have been correlated with the molecule's protein/lipid binding capacity conferred by its octyl moiety. This article, following an initial review of CA's historical applications, introduces CA's relatively new application in downstream processing of monoclonal antibodies (mAbs). By taking advantage of CA mediated impurity precipitation and virus inactivation, it might be possible to develop a two-column purification process in replacement of the standard three-column process without compromising product quality. Highlights • Caprylic acid (CA)'s historical applications as albumin stabilizer, non-IgG fraction precipitant and bactericidal agent are reviewed. • The mechanisms through which CA achieves its effects are informed. • CA's relatively new applications as host cell protein (HCP) precipitant and virus inactivating agent in downstream processing of monoclonal antibodies (mAbs) are introduced. • The possibility of replacing the standard three-column purification process with a two-column process combined with CA treatment is discussed. [ABSTRACT FROM AUTHOR]

To investigate the glycometabolism associated mechanism in invasion and metastasis of pancreatic cancer, We screened out genes involved in anaerobic glycolysis headed by HIF-1α,using pre-established a pair of pancreatic cancer cell lines. In this study, we further detected the glucose metabolism state not only in the cells but all also in two groups of patients with different SUVmax on 18 F-FDG PET/CT. The data suggests that ROS mediated EGFR/MEK/ERK/HIF-1α loop is activated in high glucose metabolic samples both in vitro and in vivo : The increasing of HIF-1α expression is controlled by activation of EGFR/MEK/ERK pathway in hypoxia condition, HIF-1α inhibits excessive release of ROS, the reduction of ROS further activates EGFR to form a positive feedback loop. This difference is closely related to invasion and metastasis capacity of pancreatic cancer, and can be rescued by separate or combined inhibition of EGFR or HIF-1α in various degree. These results indicate a new clue to develop therapy of pancreatic cancer by regulating the glucose metabolism. [ABSTRACT FROM AUTHOR]

Background: In the human genome, 98% of DNA sequences are non-protein-coding regions that were previously disregarded as junk DNA. In fact, non-coding regions host a variety of cis-regulatory regions which precisely control the expression of genes. Thus, Identifying active cis-regulatory regions in the human genome is critical for understanding gene regulation and assessing the impact of genetic variation on phenotype. The developments of high-throughput sequencing and machine learning technologies make it possible to predict cis-regulatory regions genome wide. Results: Based on rich data resources such as the Encyclopedia of DNA Elements (ENCODE) and the Functional Annotation of the Mammalian Genome (FANTOM) projects, we introduce DECRES based on supervised deep learning approaches for the identification of enhancer and promoter regions in the human genome. Due to their ability to discover patterns in large and complex data, the introduction of deep learning methods enables a significant advance in our knowledge of the genomic locations of cis-regulatory regions. Using models for well-characterized cell lines, we identify key experimental features that contribute to the predictive performance. Applying DECRES, we delineate locations of 300,000 candidate enhancers genome wide (6.8% of the genome, of which 40,000 are supported by bidirectional transcription data), and 26,000 candidate promoters (0.6% of the genome). Conclusion: The predicted annotations of cis-regulatory regions will provide broad utility for genome interpretation from functional genomics to clinical applications. The DECRES model demonstrates potentials of deep learning technologies when combined with high-throughput sequencing data, and inspires the development of other advanced neural network models for further improvement of genome annotations. [ABSTRACT FROM AUTHOR]

Solid oxide cell (SOC) based energy conversion systems have the potential to become the cleanest and most efficient systems for reversible conversion between electricity and chemical fuels due to their high efficiency, low emission, and excellent fuel flexibility. Broad implementation of this technology is however hindered by the lack of high-performance electrode materials. While many perovskite-based materials have shown remarkable promise as electrodes for SOCs, cation enrichment or segregation near the surface or interfaces is often observed, which greatly impacts not only electrode kinetics but also their durability and operational lifespan. Since the chemical and structural variations associated with surface enrichment or segregation are typically confined to the nanoscale, advanced experimental and computational tools are required to probe the detailed composition, structure, and nanostructure of these near-surface regions in real time with high spatial and temporal resolutions. In this review article, an overview of the recent progress made in this area is presented, highlighting the thermodynamic driving forces, kinetics, and various configurations of surface enrichment and segregation in several widely studied perovskite-based material systems. A profound understanding of the correlation between the surface nanostructure and the electro-catalytic activity and stability of the electrodes is then emphasized, which is vital to achieving the rational design of more efficient SOC electrode materials with excellent durability. Furthermore, the methodology and mechanistic understanding of the surface processes are applicable to other materials systems in a wide range of applications, including thermo-chemical photo-assisted splitting of H2O/CO2 and metal–air batteries. [ABSTRACT FROM AUTHOR]

Environment-friendly energy storage materials are embraced in global researches. Aiming at improving the energy storage performances of lead-free dielectric ceramics, the Sr 0.7 Bi 0.2 Ti (1–1.25 x) Nb x O 3 (SBT- x N, x = 0 ∼ 0.125) lead-free ceramics were synthesized via the conventional solid state method in this work. Outstanding total energy storage density (W total = 3.998 J/cm3), recoverable energy storage (W rec = 3.43 J/cm3), and high energy storage efficiency (η of 85.84%) were obtained when x = 0.075 under the electric field of 385 kV/cm. Meanwhile, a satisfied temperature (30 ℃−110 ℃ variation less than 14%), frequency stability (10–400 Hz variation less than 1%), and anti-fatigue characteristic (107 cycles variation less than 1%) were achieved. Furthermore, the sample exhibited a remarkable discharge energy density (W d = 3.885 J/cm3), ultrafast discharge speed (t 0.9 = 73 ns), and giant discharge power density (P d = 327.01 MW/cm3) at 400 kV/cm in charge-discharge tests. Great temperature stability (30 ℃−150 ℃ variation less than 8%) and pulse repetition frequency discharge stability (2×105 times variation less than 3.5%) were also obtained. The excellent characteristics suggest that the ceramic is a prospective candidate for advanced pulse power equipment. • High electric field of 385 kV/cm with an outstanding W rec of 3.43 J/cm3, η of 85.84%. • Ultra-fast discharge speed of 73 ns and giant P d of 327.01 MW/cm3. • Excellent anti-fatigue characteristics in P-E and pulse repetition frequency discharge tests. [ABSTRACT FROM AUTHOR]

Background: Oblique lumbar interbody fusion (OLIF) has been a popular technique for treating lumbar degenerative diseases. Previous studies have shown its efficiency in lumbar spinal stenosis; yet, only a few studies have investigated its application to severe lumbar spinal stenosis. Herein, we investigated the clinical and radiographic outcome of OLIF with percutaneous pedicle screws in the treatment of severe lumbar spinal stenosis. Methods: A total of 15 patients who underwent OLIF with percutaneous pedicle screws were retrospectively analysed. All patients were diagnosed with severe lumbar stenosis (Schizas grade C or D) through preoperative magnetic resonance image (MRI) and received OLIF combined with percutaneous pedicle screw surgery. Clinical outcomes, including visual analogue scale (VAS)-back and VAS-leg scores, and Oswestry Disability Index (ODI), as well as mean disc height (DH), mean foraminal height (FH), segmental lumbar lordosis (SLL) and cross-sectional area (CSA) of the spinal canal, were analysed before and after surgery and at the last follow-up. Intraoperative data, complications and fusion rate were also investigated. Results: OLIF combined with percutaneous pedicle screws was performed on 18 segments in 15 patients. Mean follow-up was 23.1 ± 4.6 months (range 15–29 months). VAS-back, VAS-leg, and ODI scores were significantly improved at the last follow-up. DH increased from 8.86 ± 3.06 mm before surgery to 13.31 ± 2.14 mm after; at the last follow-up, DH was 11.69 ± 1.87 mm. FH increased from 17.85 ± 2.26 mm before surgery to 22.09 ± 1.36 mm after; at the last follow-up, FH was 20.41 ± 0.99 mm. CSA of the spinal canal increased from 30.83 ± 21.15 mm2 before surgery to 74.99 ± 33.65 mm2 after the operation and 81.22 ± 35.53 mm2 at the last follow-up. The segmental LL before surgery, after surgery and at last follow-up was 20.27 ± 6.25 degrees, 20.83 ± 6.52 degrees and 19.75 ± 5.87 degrees, respectively. All patients have gained fusion at the last follow-up. Conclusion: OLIF with percutaneous pedicle screws could achieve satisfactory clinical and radiographic effects through indirect compression by increasing DH, FH and CSA of the spinal canal in severe lumbar stenosis patients. [ABSTRACT FROM AUTHOR]

Recombinant therapeutic proteins are typically produced through cell culture process. Host cell proteins (HCPs) are endogenous proteins derived from the host cells used for such bioproduction. HCPs form a major class of process-related impurities and even at low levels they can potentially compromise the safety and efficacy of biopharmaceuticals. Therefore, they need to be adequately removed via the downstream process. HCPs are complex mixtures with diverse physiochemical properties, and certain subpopulations can bind to the intended product. Hence reducing them to the generally accepted level can be challenging. This article reviews effective HCP removing strategies at different stages of downstream process for monoclonal antibodies and Fc-fusion proteins. When used in combination, these strategies can greatly enhance the chance of meeting the drug substance specifications for residual HCP. [ABSTRACT FROM AUTHOR]

We theoretically investigate the nonlinear effects of acoustic wave propagation and dispersion in a cylindrical pipe with periodically arranged Helmholtz resonators. By using the classical perturbation method in nonlinear acoustics and considering a nonlinear response up to the third-order at the fundamental frequency, the expressions of the nonlinear impedance Z NHR of the Helmholtz resonator and effective nonlinear bulk modulus B neff of the composite structure are derived. In order to confirm the nonlinear properties of the acoustic metamaterial, the transmission spectra have been studied by means of the acoustic transmission line method. Moreover, we calculate the effective acoustic impedance and dispersion relation of the system using the acoustic impedance theory and Bloch theory, respectively. It is found that with the increment of the incident acoustic pressure level, owing to the nonlinearity of the Helmholtz resonators, the resonant frequency ω 0 shifts toward the lower frequency side and the forbidden bandgap of the transmission spectrum is shown to be broadened. The perturbation method employed in this paper extends the general analytical framework for a nonlinear acoustic metamaterial. [ABSTRACT FROM AUTHOR]

In the present work, NiCrAlCoY-Al gradient composite coatings were successfully fabricated on Ti-6Al-4V alloy substrate via high-energy mechanical alloying method. The microstructures and elemental and phase composition of the coatings have been studied. Effects of both NiCrAlCoY-Al powder ratio and milling time on the fabrication of composite coating were investigated. The NiCrAlCoY-Al weight ratio 65:35 was considered the optimal powder ratio to fabricate the coating at the selected milling parameters. The high-temperature cyclic oxidation tests were performed at 850 °C and 750 °C. The fabricated sample using 65:35 wt ratio and 4 h milling time showed the best oxidation resistance due to the low mass gain, rutile TiO 2 undetected surface, and densified composite cross-section morphology. The decreased oxygen content of the oxidized cross-section line scanning results revealed the improvement of oxidation resistance. The oxidation process of the as-fabricated coating had been divided into five steps. Three protective Al 2 O 3 oxide layers together with other alloy compounds could prevent the further diffusion of oxygen. The coating could enhance the oxidation resistance of the substrate. [ABSTRACT FROM AUTHOR]

Zinc-ion hybrid supercapacitors (ZHCs) are attracting more attentions due to their high energy/power densities and safety. Pseudocapacitive materials can provide larger capacitances than carbon materials due to their specific faradaic processes. Metal-organic frameworks with good electronic conductivity and abundant redox functional groups are ideal cathodic materials. Herein, a bimetallic organic framework cathode (Co/Zn-ZIF(M24)@CC) is proposed as a high-performance cathode in Zn-ion hybrid supercapacitor. The Co/Zn-ZIF(M24)@CC cathode benefits from a dual-ion storage mechanism of the pseudocapacitive behavior of H + and the electrical double-layer capacitance behavior of Zn2+, which is methodically explored by ex situ electroanalytic characterizations. The as-prepared Co/Zn-ZIF (M24)@CC electrode achieved the highest energy density of 124.6 Wh kg−1 at 49.2 W kg−1. This study lays the foundation for the rational design of metal-organic cathodes in ZHCs. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Using anion-exchange high performance liquid chromatography under non-denaturing conditions, the conformational flexibility of adenosine-, ampicillin-, and quinine aptamers were studied. It was found that all three aptamers showed more than one species when not subjected to thermal anneal. Addition of ligand to untreated aptamers did not significantly change the structural distribution. Upon heating followed by slow cooling, however, all three aptamers were found to exist virtually solely in one structure, presumably the partial hairpin species. It was also found that sonication of quinine aptamer, but not adenosine and ampicillin aptamer, led to its elution off HPLC as virtually a single species. These changes in conformational distribution as a result of thermal anneal or sonication were further confirmed by UV/vis and circular dichroism spectroscopy, as well as melt curves. The findings provided basis for future optimization of aptamer selection and preparation, where thermal anneal can help optimize selection efficiency and improve the consistency in the interpretation of results. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bifunctional nitrogen doped carbon network as interlayer (NCL) in cells to suppress the dendrite growth. • NCL can balance the interfacial electrostatic field on Zn surface and guide Zn ions to deposit uniformly. • The nitrogen doped carbon active sites can reconstruct the typical solvation structure. • The Zn/Zn symmetric cell acquires a cycle life of over 4000 h. Aqueous rechargeable zinc-ion batteries promise attractive advantages including safety, high energy density, and low cost. However, the uncontrollable dendrite growth and intricate side-reactions impede the practical application. Herein, we report a bifunctional nitrogen doped carbon network as interlayer (NCL) in cells to suppress the dendrite growth. In physical effect, NCL can balance the interfacial electrostatic field of Zn surface and guide Zn ions to deposit uniformly. In chemical effect, the nitrogen doped carbon active sites can reconstruct the typical solvation structure of [Zn(H 2 O) 6 ]2+, and further promote the de-solvation process. Benefiting from the synergetic bifunctional interlayer both physically and chemically, dendrite and side-reactions are obviously restrained during repeated Zn plating/stripping procedures. Finally, the NCL-Zn/NCL-Zn symmetric cell acquires a cycle life of over 4000 h and persists for over 125 h even at a depth of discharge (DOD) of 38%. [ABSTRACT FROM AUTHOR]

For monoclonal antibodies (mAbs) produced in mammalian cells, viral safety is a critical concern. The downstream process, in addition to removing other impurities, needs to ensure robust clearance (removal or inactivation) of potential endogenous and adventitious viruses. In general, Protein A and polishing chromatography steps all can provide certain level of virus removal. Chromatographic removal combined with virus inactivation and nanofiltration usually provides adequate virus clearance across the overall downstream process. This article reviews the virus clearance capability of commonly used column chromatography, with attention to possible interference of virus-mAb interaction on virus removal. In addition, the potential of using viral surrogate as a safe alternative to live virus for assessing viral clearance is briefly discussed. • Virus-mAb interactions negatively impact viral removal by Protein A and other types of column chromatography. • Including interaction-disrupting additives to Protein A wash buffer can improve this step's viral clearance capacity. • Virus surface charge distribution is more relevant than pI in determining its interaction with IEX resins. • Viral surrogates are potential safe alternatives to live viruses for assessing a unit operation's viral removal capability. [ABSTRACT FROM AUTHOR]

This paper extends previous thermal models of the vanadium redox flow battery to predict temperature profiles within multi-cell stacks. This involves modelling the thermal characteristics of the stack as a whole to modelling each individual cell. The study investigates the thermal behaviour for two different scenarios: during standby periods when the pumps are turned off, and in a residential power arbitrage scenario for two types of membranes. It was found that the temperature gradient across the cells is most significant during the standby case, with the simulation results showing completely different thermal behaviours between the two systems. [ABSTRACT FROM AUTHOR]

Sparse linear models approximate target variable(s) by a sparse linear combination of input variables. Since they are simple, fast, and able to select features, they are widely used in classification and regression. Essentially they are shallow feed-forward neural networks that have three limitations: (1) incompatibility to model nonlinearity of features, (2) inability to learn high-level features, and (3) unnatural extensions to select features in a multiclass case. Deep neural networks are models structured by multiple hidden layers with nonlinear activation functions. Compared with linear models, they have two distinctive strengths: the capability to (1) model complex systems with nonlinear structures and (2) learn high-level representation of features. Deep learning has been applied in many large and complex systems where deep models significantly outperform shallow ones. However, feature selection at the input level, which is very helpful to understand the nature of a complex system, is still not well studied. In genome research, the cis-regulatory elements in noncoding DNA sequences play a key role in the expression of genes. Since the activity of regulatory elements involves highly interactive factors, a deep tool is strongly needed to discover informative features. In order to address the above limitations of shallow and deep models for selecting features of a complex system, we propose a deep feature selection (DFS) model that (1) takes advantages of deep structures to model nonlinearity and (2) conveniently selects a subset of features right at the input level for multiclass data. Simulation experiments convince us that this model is able to correctly identify both linear and nonlinear features. We applied this model to the identification of active enhancers and promoters by integrating multiple sources of genomic information. Results show that our model outperforms elastic net in terms of size of discriminative feature subset and classification accuracy. [ABSTRACT FROM AUTHOR]

A dynamic plug flow reactor model for a single cell VRB system is developed based on material balance, and the Nernst equation is employed to calculate cell voltage with consideration of activation and concentration overpotentials. Simulation studies were conducted under various conditions to investigate the effects of several key operation variables including electrolyte flow rate, upper SOC limit and input current magnitude on the cell charging performance. The results show that all three variables have a great impact on performance, particularly on the possibility of gassing during charging at high SOCs or inadequate flow rates. Simulations were also carried out to study the effects of electrolyte imbalance during long term charging and discharging cycling. The results show the minimum electrolyte flow rate needed for operation within a particular SOC range in order to avoid gassing side reactions during charging. The model also allows scheduling of partial electrolyte remixing operations to restore capacity and also avoid possible gassing side reactions during charging. Simulation results also suggest the proper placement for cell voltage monitoring and highlight potential problems associated with setting the upper charging cut-off limit based on the inlet SOC calculated from the open-circuit cell voltage measurement. [ABSTRACT FROM AUTHOR]

The majority of the human genome consists of non-coding regions that have been called junk DNA. However, recent studies have unveiled that these regions contain cis -regulatory elements, such as promoters, enhancers, silencers, insulators, etc. These regulatory elements can play crucial roles in controlling gene expressions in specific cell types, conditions, and developmental stages. Disruption to these regions could contribute to phenotype changes. Precisely identifying regulatory elements is key to deciphering the mechanisms underlying transcriptional regulation. Cis -regulatory events are complex processes that involve chromatin accessibility, transcription factor binding, DNA methylation, histone modifications, and the interactions between them. The development of next-generation sequencing techniques has allowed us to capture these genomic features in depth. Applied analysis of genome sequences for clinical genetics has increased the urgency for detecting these regions. However, the complexity of cis -regulatory events and the deluge of sequencing data require accurate and efficient computational approaches, in particular, machine learning techniques. In this review, we describe machine learning approaches for predicting transcription factor binding sites, enhancers, and promoters, primarily driven by next-generation sequencing data. Data sources are provided in order to facilitate testing of novel methods. The purpose of this review is to attract computational experts and data scientists to advance this field. [ABSTRACT FROM AUTHOR]

For CHO expressed monoclonal antibodies (mAbs), host cell proteins (HCPs) represent a major class of process-related impurities and their removal is a key focus of downstream process development. HCPs are highly heterogeneous in nature, differing in molecular weight, isoelectric point and hydrophobicity, and some of them can be difficult to remove. Although Protein A affinity chromatography alone can typically remove more than 90% of HCPs in the clarified culture harvest, in many cases reducing HCPs in the final drug product to an acceptable level (e.g., <100 ppm) can still be a challenging task. The relative difficulty of HCP clearance is case dependent and in certain cases a small population of HCPs can persist throughout the downstream process. This article reviews the two major mechanisms that contribute to copurification of CHO HCPs, namely leaching from chromatin heteroaggregates and nonspecific HCP-mAb association. In addition, strategies that can minimize the impact of these two factors are briefly discussed. • The two reasons behind HCP copurification are leaching from chromatin heteroaggregates and nonspecific association with mAb. • Advance chromatin reduction can significantly improve HCP clearance at the capture step. • HCP-mAb interactions can be disrupted by including additives (e.g., NaCl, Arg, sodium caprylate) in wash/incubation buffers. • AEX Hybrid Purifier and activated carbon filter are effective tools for removing DNA/chromatin and HCPs, respectively. [ABSTRACT FROM AUTHOR]

High-current-density electrolysis, integrated interface, micro-channel anodes, nano-channel anodes, SOECs Keywords: high-current-density electrolysis; integrated interface; micro-channel anodes; nano-channel anodes; SOECs EN high-current-density electrolysis integrated interface micro-channel anodes nano-channel anodes SOECs 1 1 1 07/29/22 20220727 NES 220727 B Solid-Oxide Electrolysis Cells b In article number 2200899, Bo Yu and co-workers fabricate a novel solid oxide electrolysis cell with the characteristics of integrated anode-electrolyte interface, vertically straight anode micro channel scaffold, and La SB 0.6 sb Sr SB 0.4 sb CoO SB 3- sb catalyst nano layers, which demonstrates stable steam electrolysis performance under an ultra-high current density of 5.96 A cm SP -2 sp at 800 °C and 1.3 V constant operating voltage. A Novel Solid Oxide Electrolysis Cell with Micro-/Nano Channel Anode for Electrolysis at Ultra-High Current Density over 5 A cm-2 (Adv. [Extracted from the article]

Solid‐Oxide Electrolysis Cells In article number 2200899, Bo Yu and co‐workers fabricate a novel solid oxide electrolysis cell with the characteristics of integrated anode–electrolyte interface, vertically straight anode micro channel scaffold, and La0.6Sr0.4CoO3−δ catalyst nano layers, which demonstrates stable steam electrolysis performance under an ultra‐high current density of 5.96 A cm−2 at 800 °C and 1.3 V constant operating voltage. [ABSTRACT FROM AUTHOR]

There are many paradigms for pattern classification such as the optimal Bayesian, kernel-based methods, inter-class border identification schemes, nearest neighbor methods, nearest centroid methods, among others. As opposed to these, this paper pioneers a new paradigm, which we shall refer to as the nearest border (NB) paradigm. The philosophy for developing such a NB strategy is as follows: given the training data set for each class, we shall attempt to create borders for each individual class. However, unlike the traditional border identification (BI) methods, we do not undertake this by using inter -class criteria; rather, we attempt to obtain the border for a specific class in the d -dimensional hyper-space by invoking only the properties of the samples within that class . Once these borders have been obtained, we advocate that testing is accomplished by assigning the test sample to the class whose border it lies closest to . This claim appears counter-intuitive, because unlike the centroid or the median, these border samples are often “outliers” and are, really, the points that represent the class the least. Moreover, inter-class BI methods intuitively outperform within-class ones. However, we have formally proven this claim, and the theoretical results have been verified by rigorous experimental testing on artificial and real-life data sets. While the solution we propose is distantly related to the reported solutions involving prototype reduction schemes (PRSs) and BI algorithms, it is, most importantly, akin to the recently proposed “ anti -Bayesian” methods of classification. [ABSTRACT FROM AUTHOR]

In the recent years, non-negative matrix factorization and sparse representation models have been successfully applied in high-throughput biological data analysis due to its interpretability and robustness to noise. In this paper, we propose a unified matrix factorization model, coined versatile sparse matrix factorization (VSMF) model, for biological data analysis. We discuss the modelling, optimization, and applications of VSMF. We show that many well-known sparse matrix factorization models are specific cases of our VSMF. Through tuning parameters, sparsity, smoothness, and non-negativity can be easily controlled in VSMF. Our computational experiments for feature extraction, feature selection, and clustering corroborate the advantages of VSMF. [ABSTRACT FROM AUTHOR]

Abstract: A non-negative least squares classifier is proposed in this paper for classifying under-complete data. The idea is that unknown samples can be approximated by sparse non-negative linear combinations of few training samples. Based on sparse coefficient vectors representing the training data, a sparse interpreter can then be used to predict the class label. We have devised new sparse methods which can learn data containing missing value, which can be trained on over-complete data, and which also apply to tensor data and to multi-class data. Permutation test shows that our approach requires a small number of training samples to obtain significant accuracy. Statistical comparisons on various data shows that our methods perform as well as support vector machines while being faster. Our approach is very robust to missing values and noise. We also show that with appropriate kernel functions, our methods perform very well on three-dimensional tensor data and run fairly fast. [Copyright &y& Elsevier]

There are two different definitions of input–output decoupling of Boolean control networks (BCNs), one of which depends on system decomposition and the other does not. In this paper, input–output decoupling of BCNs is investigated under the algebraic representation frame of BCNs. Necessary and sufficient vertex partition conditions for both the definitions of input–output decoupling of BCNs are proposed. Based on the vertex partition conditions, the essential difference between the two concepts of input–output decoupling is revealed for the first time. Finally, three illustrative examples are provided to validate the obtained theoretical results. [ABSTRACT FROM AUTHOR]

Abstract: LL-37 is a human antimicrobial peptide that has been shown to possess multiple functions in host defense. In this report, the peptide was expressed as a fusion with a thioredoxin–SUMO dual-tag. Upon SUMO protease mediated cleavage at the SUMO/peptide junction, LL-37 with its native N-terminus was generated. The released peptide was separated from the dual-tag and cleavage enzyme by size-exclusion chromatography. Mass spectrometry analysis proves that the recombinant peptide has a molecular weight as theoretically expected for its native form. The produced peptide displayed antimicrobial activity against Escherichia coli K-12. On average, 2.4mg peptide was obtained from one liter of bacterial culture. Thus, the described approach provides an effective alternative for producing active recombinant LL-37 with its natural amino acid sequence in E. coli. [Copyright &y& Elsevier]

Guanylate cyclase (GC, cGMPase) is a key enzyme in organisms, catalyzing the synthesis of cGMP from GTP, thus making cGMP work. cGMP plays a vital role in the regulation of cell and biological growth as a second messenger in signaling pathways. In this study, we screened and identified cGMPase from the razor clam Sinonovacula constricta, which encoded 1257 amino acids and was widely expressed in different tissues, especially the gill and liver. We also screened one double-stranded RNA (dsRNA), cGMPase, which was used to knockdown cGMPase at three larval metamorphosis development stages: trochophores-veliger larve, veliger larve-umbo larve, and umbo larve-creeping larvae. We showed that interference at these stages significantly inhibited larval metamorphosis and survival rates. cGMPase knockdown resulted in an average metamorphosis rate of 60% and an average mortality rate of 50% when compared with control clams. After 50 days, shell length and body weight were inhibited to 53% and 66%, respectively. Thus, cGMPase appeared to regulate metamorphosis development and growth in S. constricta. By examining the role of the key gene in the metamorphosis development of S. constricta larvae and the growth and development period, we can provide some data reference for studying the growth and development mechanism of shellfish, and the results provided basic information for the breeding of S. constricta. [ABSTRACT FROM AUTHOR]

Many aquatic organisms are negatively affected by exposure to high copper concentrations. We investigated the biochemical response of the mussel Mytilus coruscus (Mytiloida: Mytilidae) to copper exposure. In vivo bioassays using M. coruscus and different copper concentrations were conducted. The activity of six biomarkers, namely superoxide dismutase (SOD), catalase (CAT), acid phosphatase (ACP), alkaline phosphatase (AKP), glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) were measured. Survival rates decreased with increased copper concentrations and exposure times. The LC values at 48, 72, and 96 h exposure were 0.48, 0.37, and 0.32 mg/L, respectively. Within digestive glands, CAT activity increased with increasing Cu concentrations. The activity of AKP showed no significant change, while the remaining four enzymes showed decreasing activity with increasing Cu concentrations. Within the gills, AKP activity increased when the Cu concentration was 0.05 mg/L, but showed no significant changes at higher concentrations. Activity of CAT and ACP within gills tended to decrease with increasing Cu concentration. The activity of SOD and GPT decreased at an exposure concentration of 0.2 mg/L. GOT activity within gills decreased at 0.1 mg/L and increased at an exposure concentration of 0.2 mg/L. Within the adductor muscle, AKP activity increased at 0.05 mg/L but did not change at higher exposure concentrations. ACP activity within adductor muscle tissue showed no change, while activities of CAT, GOT and GPT decreased with increasing Cu concentrations. SOD activity within the adductor muscle tissue significantly decreased at the 0.02, 0.05 and 0.2 mg/L exposure concentrations. Our results show tissue specific differences for the six biomarkers in for M. coruscus. Our findings provide the basis for the establishment of reference activity levels against which biomarker changes can be estimated, and are essential preliminary steps in development of in vivo bioassays. [ABSTRACT FROM AUTHOR]

Abstract: The extremely tight binding between biotin and avidin or streptavidin makes labeling proteins with biotin a useful tool for many applications. BirA is the Escherichia coli biotin ligase that site-specifically biotinylates a lysine side chain within a 15-amino acid acceptor peptide (also known as Avi-tag). As a complementary approach to in vivo biotinylation of Avi-tag-bearing proteins, we developed a protocol for producing recombinant BirA ligase for in vitro biotinylation. The target protein was expressed as both thioredoxin and MBP fusions, and was released from the corresponding fusion by TEV protease. The liberated ligase was separated from its carrier using HisTrap HP column. We obtained 24.7 and 27.6mg BirA ligase per liter of culture from thioredoxin and MBP fusion constructs, respectively. The recombinant enzyme was shown to be highly active in catalyzing in vitro biotinylation. The described protocol provides an effective means for making BirA ligase that can be used for biotinylation of different Avi-tag-bearing substrates. [Copyright &y& Elsevier]

Abstract: LL-37 is the only cathelicidin-derived antimicrobial peptide found in humans and it has a multifunctional role in host defense. The peptide has been shown to possess immunomodulatory functions in addition to antimicrobial activity. To provide sufficient material for biological and structural characterization of this important peptide, various systems were developed to produce recombinant LL-37 in Escherichia coli. In one previous approach, LL-37 coding sequence was cloned into vector pET-32a, allowing the peptide to be expressed as a thioredoxin fusion. The fusion protein contains two thrombin cleavage sites: a vector-encoded one that is 30-residue upstream of the insert and an engineered one that is immediately adjacent to LL-37. Cleavage at these two sites shall generate three fragments, one of which is the target peptide. However, when the fusion protein was treated with thrombin, cleavage only occurred at the remote upstream site. A plausible explanation is that the thrombin site adjacent to LL-37 is less accessible due to the peptide’s aggregation tendency and cleavage at the remote site generates a fragment, which forms a large aggregate that buries the intended site. In this study, I deleted the vector-encoded thrombin site and S tag in pET-32a, and then inserted the coding sequence for LL-37 plus a thrombin site into the modified vector. Although removing the S tag did not change the oligomeric state of the fusion protein, deletion of the vector-encoded thrombin site allowed the fusion to be cleaved at the engineered site to release LL-37. The released peptide was separated from the carrier and cleavage enzyme by size-exclusion chromatography. This new approach enables a quick production of high quality active LL-37 with a decent amount. [Copyright &y& Elsevier]

Abstract: La2CuO4 and La2−xCaxCuO4 crystallites were prepared via a simple sol–gel process. The as-prepared La2CuO4 and La2−xCaxCuO4 crystallites were characterized by X-ray diffraction, transmission electron microscope and UV–vis–NIR spectra. Results show that the grain size of La2CuO4 crystallites increases with the increase of heat treatment temperature from 600°C to 800°C. Optical properties show that La2CuO4 crystallites have broad absorption both in the UV–vis region and in the NIR region. The band gap of the as-prepared crystallites decreases from 1.367eV to 1.284eV with the increase of calcination temperature from 600°C to 800°C. In the series of La2−xCaxCuO4 compounds (x=0.05, 0.08, 0.10, 0.12, 0.15 and 0.20), all of the samples exhibit an orthogonal crystal structure and the solubility limit of Ca2+ in La2CuO4 is within the range of x=0.12–0.15. In the whole UV–vis–NIR region, La2−xCaxCuO4 crystallites exhibit a broad absorption and the corresponding band gap first increases and then decreases with increasing of Ca2+ content. [Copyright &y& Elsevier]