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On May 21, 2023, the Macao Science Satellite-1B (MSS-1B), a low-inclination, low-latitude, and high-precision scientific exploration satellite for geomagnetic fields and space environments, was successfully launched. The solar X-ray detector (SXD), one of the two major scientific payloads onboard the MSS-1B, has obtained a large amount of solar X-ray radiation data, which reveals the distribution law of the magnetic field in the low Earth orbit, as well as the coupling law of the Earth’s magnetic field and the solar radiation and energy particle distributions. First, the overall design of the multi-detection-unit, broad-energy-range, small-volume, and low-power SXD was implemented to achieve the scientific objectives of the mission. Second, the technical indicators of the instrument were decomposed into various components, and the key technologies, such as collimator, processing circuit, thermal, and payload dataset designs, were reviewed. Third, the backgrounds, including electronic noise, cosmic diffuse X-ray background, and high-energy background in the Earth’s radiation belts in and out of the field of view, were analyzed for the instrument. Then, the ground calibrations of the energy response, detection efficiency, and temperature-dependent peak drift of the SXD flight model were conducted. Finally, the in-orbit temperature, energy spectrum data, background, and solar flare process observation of the instrument in the in-orbit test stage are presented, verifying the instrument design, analysis, and ground calibration, providing a foundation for obtaining accurate solar X-ray radiation data, and achieving the scientific objectives of the satellite.

OVERVIEW: Our study explores the nature of big data-embedded new product development (NPD) and to what extent big data influences NPD project success. Using data collected from 558 NPD projects, our study shows that embedding big data in NPD processes promotes NPD project success, but the effects vary for the seven different stages of NPD. A data-driven culture--characterized by senior management's emphasis on data-driven decision-making and a reward system for big data-embedded NPD--can promote the implementation of big data-embedded NPD. We offer specific recommendations for managers considering or implementing big data-embedded NPD. KEYWORDS: Big data, Big data-embedded new product development process, Data-driven culture, Senior management emphasis, Reward system, Firms use big data collected from sensors embedded in manufacturing equipment, social media, and other consumer devices such as personal computers and laptops, to identify innovation problems, analyze innovation opportunities, [...]

Multivariate time series forecasting holds substantial practical significance, facilitates precise predictions, and informs decision-making. The complexity of nonlinear relationships and the presence of higher-order features in multivariate time series data have sparked a burgeoning interest in leveraging deep learning approaches for such forecasting tasks. Existing methods often use pre-scaled neural networks, whose reliability and generalization can pose a challenge. In this study, the authors propose an instance-wise graph-based Mallows model averaging (IGMMA) framework for multivariate time series prediction. The framework incorporates a model averaging module into the network, where extracted features are utilized as inputs for candidate linear models. These linear models are combined with weights to create a new linear layer, forming a novel graph neural network model. Moreover, the network loss function is modified based on the Mallows criterion, where penalties are imposed on the parameters and the weights separately. The authors use the proposed method to predict multicommodity futures prices, and the empirical results show that IGMMA has superior predictive accuracy even when small neural networks are used. This indicates that the model averaging module significantly reduces the parameters required for deep learning training, which enables the training of multiple small models as an alternative to training a large model.

This article is concerned with the optimal fault detection issues for discrete-time nonlinear systems with the aid of Takagi–Sugeno fuzzy dynamic modeling technique. To this end, in the first part of this article, the nonlinear system is formulated in the time-varying fuzzy manner, and based on it, a unified fault detection approach is developed by solving a multiobjective optimization problem. In this sense, the optimal tradeoff between fault detectability and robustness against unknown inputs is ensured by solving the Riccati equation. Meanwhile, a fuzzy fault detection approach is studied in the second part of this article based on piecewise-fuzzy Lyapunov functions, which is realized by solving linear matrix inequalities. Two examples are given at the end of this article to demonstrate the proposed approaches.

The multifactorial evolutionary algorithm (MFEA) is one of the most widely used evolutionary multitasking (EMT) algorithms. The MFEA implements knowledge transfer among optimization tasks via crossover and mutation operators and it obtains high-quality solutions more efficiently than single-task evolutionary algorithms. Despite the effectiveness of MFEA in solving difficult optimization problems, there is no evidence of population convergence or theoretical explanations of how knowledge transfer increases algorithm performance. To fill this gap, we propose a new MFEA based on diffusion gradient descent (DGD), namely, MFEA-DGD in this article. We prove the convergence of DGD for multiple similar tasks and demonstrate that the local convexity of some tasks can help other tasks escape from local optima via knowledge transfer. Based on this theoretical foundation, we design complementary crossover and mutation operators for the proposed MFEA-DGD. As a result, the evolution population is endowed with a dynamic equation that is similar to DGD, that is, convergence is guaranteed, and the benefit from knowledge transfer is explainable. In addition, a hyper-rectangular search strategy is introduced to allow MFEA-DGD to explore more underdeveloped areas in the unified express space of all tasks and the subspace of each task. The proposed MFEA-DGD is verified experimentally on various multitask optimization problems, and the results demonstrate that MFEA-DGD can converge faster to competitive results compared to state-of-the-art EMT algorithms. We also show the possibility of interpreting the experimental results based on the convexity of different tasks.

Background: Laparoscopic treatment has been increasingly adopted for giant hepatic hemangioma (HH), but the role of liver resection or enucleation remains uncertain. The aim of this study is to compare the laparoscopic resection (LR) with laparoscopic enucleation (LE) for HH, and to provide evidence on how to choose the most suitable approach for HH. Methods: A retrospective analysis of HH patients underwent laparoscopic treatment between March 2015 and August 2022 was performed. Perioperative outcomes were compared based on the surgical approaches, and risk factors for increased blood loss was calculated by logistic regression analysis. Results: A total of 127 patients in LR group and 287 patients in LE group were enrolled in this study. The median blood loss (300 vs. 200 mL, P< 0.001) was higher in LE group than that in LR group. Independent risk factors for blood loss higher than 400 mL were tumor size ≥ 10 cm, tumor adjacent to major vessels, tumor occupying right liver or caudate lobe, and the portal phase enhancement ratio (PER) ≥ 38.9%, respectively. Subgroup analysis showed that LR was associated with less blood loss (155 vs. 400 mL, P< 0.001) than LE procedure in patients with high PER value. Both LR and LE approaches exhibited similar perioperative outcomes in patients with low PER value. Conclusions: Laparoscopic treatment for HH could be feasibly and safely performed by both LE and LR. For patients with PER higher than 38.9%, the LR approach is recommended. Graphical abstract:

Host ANP32 family proteins are crucial for maintaining the activity of influenza RNA polymerase and play an important role in the cross-species transmission of influenza viruses. To date, the molecular properties of equine ANP32 (eqANP32) protein are poorly understood, particularly the mechanisms that affect equine influenza virus (EIV) RNA polymerase activity. Here, we found that there are six alternative splicing variants of equine ANP32A (eqANP32A) with different levels of expression. Further studies showed that these six splicing variants of eqANP32A supported the activity of EIV RNA polymerase to varying degrees, with the variant eqANP32A_X2 having the highest expression abundance and exhibiting the highest support of polymerase activity. Sequence analysis demonstrated that the differences in the N-Cap regions of the six splicing variants significantly affected their N-terminal conformation, but did not affect their ability to bind RNA polymerase. We also demonstrated that there is only one transcript of eqANP32B, and that this transcript showed only very low support to the EIV RNA polymerase. This functional defect in eqANP32B is caused by the sequence of the 110–259 amino acids at its C-terminus. Our results indicated that it is the eqANP32A_X2 protein that mainly determines the efficiency of the EIV replication in horses. In conclusion, our study parsed the molecular properties of eqANP32 family proteins and revealed the sequence features of eqANP32A and eqANP32B, suggesting for the first time that the N-Cap region of ANP32A protein also plays an important role in supporting the activity of the influenza virus polymerase.

ABSTRACTThe digestive tract development of the Pelodiscus sinensisembryo is described through the observation of the embryonic morphology on hematoxylin and eosin stained tissue sections. During the first 9 days of embryonic development, the anterior intestine of the embryo divides into the oral cavity, pharyngeal cavity, esophagus, stomach, and small intestine, while the caudal intestine differentiates into the cloaca, the anterior and caudal tubes of the large intestine. Between days 10–24, the wall of the digestive tract forms a two-layer structure consisting of mucosa and submucosa. The endoderm evolves into epithelial tissue in each part of the digestive tract, the mesoderm goes from a dense cluster of cells to looser mesenchymal tissue then divides into loose connective tissue, mesothelium, and muscle tissue. There is no clear temporal boundary between development of mesenchymal tissue and the early loose connective tissue, which is a gradual process.

Chalcane-containing dimers are major compounds identified from dragon’s blood, the red resin that accumulates in Dracaenatrees after injury. The key step for the formation of these dimers was a p-quinone methide (p-QM, 3) mediated nonenzymatic Michael addition. Compound 3is derived from the spontaneous dehydration of chalcane alcohol-M274 (2). Two dihydroflavonol-4-reductases, discovered in D. cambodiana, reduce dihydrochalcone-M272 (7) to 2. Moreover, the application potential of p-QMs was demonstrated using a 3-like p-QM to synthesize diverse dimeric derivatives.

ABSTRACTOverview: Previous research has shown that market-oriented firms outperform their peers. Why are some firms such outstanding performers in market orientation (MO)? This study identifies three categories of new technology tools that have emerged in the past few years—big data analytics, artificial intelligence (AI), and social media marketing research—and assesses how each category enhances MO. The empirical evidence from 442 firms indicates that all three categories have significant impacts on MO, with AI being the most effective, followed by big data analytics and social media marketing research, respectively. We outline how very successful firms adopt these new technology tools and offer managerial implications that can guide senior executives looking to increase MO.

Superamphiphobic surfaces have great potential applications in flame resistance, anti-icing, self-cleaning, anti-adhesion, micro-flow control and so on. However, the surface durability is poor owing to the limitation of design principles. In recent years, a lot of efforts have been carried out on the morphology, structure, and stability of superamphiphobic surfaces, resulting in significant improvement in their surface superwetting properties. In this review, we present a brief classification of the morphological types of superamphiphobic surfaces and summary of the recent progress of researches on the stability of superamphiphobic surfaces. Several testing methods of mechanical and chemical stability are listed in the article, together with the characteristic results, to provide a better and more detailed understanding of the current research status on superamphiphobic surface stability, which will be of considerable importance as a reference guide for our future researches. Of course, there are still some issues that need to be addressed for the application of superamphiphobic surfaces at large scale, and this is where our future researches will be directed. Finally, we discuss the challenges as well as the prospects in the study of superamphiphobic surfaces.

Phycoerythrin (PE) is a natural water-soluble pigment protein with characteristic phycobilins and is sensitive to thermal and light environmental changes. In this study, PE was extracted from Porphyra haitanensisand PE–oligochitosan complexes (POC) were fabricated by a self-assembly approach. The effects of cationic oligochitosan on the binding interaction, structure, size distribution, and color stability of PE were evaluated. The stoichiometric number nwas calculated to be 21.67 ± 2.65 (oligochitosan/PE) and the binding constant K was (6.47 ± 0.48) × 105M–1. Cationic oligochitosan could electrostatically interact with PE and affect the PE structure by increasing the α-helix content. In addition, high concentrations of oligochitosan led to the formation of dense phycoerythrin protein granules. Moreover, at a reaction ratio of 20.0:1 (oligochitosan/PE), being approximately the predicted stoichiometric number n, the thermal stability (40–80 °C), natural light stability, and ultraviolet light irradiation (254 nm) stability of the POC were improved. This study provides an approach to reduce the susceptibility of PE upon environmental changes by forming a stable self-assembly complex, which will promote the application of PE as a natural pigment protein in food and chemical applications.

OverviewOrganizations are rapidly adopting artificial intelligence (AI) to solve business problems, yet they are only beginning to harness its benefits. Published literature lacks empirical evidence regarding the value of deploying AI for innovation success. This study investigates how and where to deploy AI in the new product development (NPD) process. We present three lessons learned and three best practices for successful deployment of AI technologies for NPD success.

ABSTRACTThe research on hatching ecology of the Chinese softshell turtle Trionyx sinensishas essential guiding roles to clarify the physiological and ecological mechanism of reptile evolution. The aim of this study is to describe the histological changes, differentiation, and maturation of some functional cells during the genesis and development of the liver and pancreas of the Chinese softshell turtle T. sinensis. Softshell turtle eggs were incubated under artificial conditions and hatched within 41–45 days. Hematoxylin and eosin-stained embryonic pancreas and liver were examined at various time points from 2 to 31 days and compared with that of other reptiles, amphibians, fishes, and birds in the literature. Immunohistochemical assay for glucagon and insulin was performed on paraformaldehyde-fixed embryos to identify functional cells in the pancreas. Pancreatic endocrine cells of T. sinensishave secretory ability at day 26 of embryonic development, and the dispersed pancreatic endocrine cells may be the result of the incomplete pancreatic development.

Background: Although long-term outcomes may be comparable between laparoscopic liver resection (LLR) and open liver resection (OLR) for hepatocellular carcinoma (HCC), there has been little discussion regarding the patterns of recurrence after LLR. Methods: Patients with HCC who underwent hepatectomy between April 2015 and November 2018 were included in this study. The recurrence patterns were analyzed in detail. The recurrence outcomes following laparoscopic versus OLR for HCC were compared after 1:2 propensity score matching. Potential risk factors for recurrence were also assessed with Cox proportional risk models. Results: Among 425 patients after LLR, 144 (33.8%) experienced recurrence at the last follow-up, with a median recurrence-free survival (RFS) of 10.0 months (range 1–58 months). The most frequent recurrence site was the liver (n= 99, 68.8%), followed by the surgical margin (n= 15, 10.4%) and distant metastases (n= 12, 8.3%). Liver recurrence with distant metastasis (n= 10, 6.9%) tended to occur early (median 8.0 months), while peritoneal recurrence (n= 8, 5.6%) occurred later (median 14.0 months). A total of 120 (83.3%) patients had recurrence within 2 years after LLR. No trocar site recurrence was observed in this study. The recurrence patterns, timing, and treatment did not show significant differences between the LLR and OLR. The independent risk factors for recurrence included ALBI grade, postoperative α-fetoprotein > 8 ng/ml, tumor size > 5 cm, surgical margin ≤ 1 cm, and multiple tumors. Patients with recurrence had 1- and 5-year overall survival rates of 81.1% and 60.7%, respectively, compared with rates of 95.8% and 92.9% for patients without recurrence (P< 0.000). Conclusion: This study suggested that intrahepatic recurrence was still the most common recurrence pattern for HCC after LLR and that LLR did not increase the risk of trocar hole recurrence or implantation. Most cases of recurrence occurred within 2 years after LLR, suggesting that surveillance should be targeted to early recurrence.

AbstractIs organizational slack good or bad for firm performance? Research addressing this question has obtained mixed results. Such studies have focused mainly on the impact of environmental conditions on the slack–performance relationship. In this study, instead of focusing on the uncontrollable external environment, we consider actions determined by firms internally, in particular strategic planning. Using data from 183 US firms, we explore the connection between organizational slack and firm performance with different levels of strategic planning. The results suggest that at low levels of strategic planning the slack–performance relationship is linear, while at high levels of strategic planning this relationship is inverse U shaped. We discuss the theoretical and practical implications of these findings.

Berberine (BBR) is an isoquinoline alkaloid extracted from several commonly used Chinese herbs. Our previous studies demonstrated BBR‐mediated alleviation of lung injury due to inflammation and decrease in the mortality of mice with influenza viral pneumonia. The recent argument of autophagy against inflammatory responses has aroused wide concerns. This study focuses on the reactive oxygen species‐Nod‐like receptor protein 3 (ROS‐NLRP3) pathway to investigate whether BBR inhibits NLRP3 inflammasome activation by inducing mitophagy. Our results demonstrate that BBR and mitochondrion‐targeted superoxide dismutase mimetic (Mito‐TEMPO; a specific mitochondrial ROS scavenger) significantly restricted NLRP3 inflammasome activation, increased mitochondrial membrane potential (MMP), and decreased mitochondrial ROS (mtROS) generation in J774A.1 macrophages infected with PR8 influenza virus. These observations suggest that the inhibitory effects of BBR on NLRP3 inflammasome activation were associated with the amelioration of mtROS generation. BBR treatment induced regular mitophagy, as evident from the increase in microtubule‐associated protein 1 light chain 3 II, decrease in p62, colocalization of LC3 and mitochondria, and formation of autophagosomes. However, 3‐methyladenine, an autophagy inhibitor, reversed the inhibitory effects of BBR on mitochondrial damage and NLRP3 inflammasome activation in influenza virus‐infected macrophages, indicating the involvement of mitophagy in mediating the inhibitory effects of BBR on NLRP3 inflammasome activation. Furthermore, the knockdown of Bcl‐2/adenovirus E18‐19‐kDa interacting protein 3 (BNIP3) expression attenuated the effects of BBR on mitophagy induction to some extent, suggesting that the BBR‐induced mitophagy may be, at least in part, mediated in a BNIP3‐dependent manner. Similar results were obtained in vivo using a mouse model of influenza viral pneumonia that was administered with BBR. Taken together, these findings suggest that restricting NLRP3 inflammasome activation by decreasing ROS generation through mitophagy induction may be crucial for the BBR‐mediated alleviation of influenza virus‐induced inflammatory lesions. Berberine inhibited influenza virus‐induced excessive inflammatory responses, restricting NLRP3 inflammasome activation by decreasing ROS generation and inducing mitophagy.

A visualization approach for process fault detection using bikernel t-distributed stochastic neighbor embedding (bikernel t-SNE) is described in this paper. Bikernel t-SNE preserves the dimension-reduction ability of the basic t-SNE and enables explicit out-of-sample extensions. First, the explicit projections between high-dimensional data and low-dimensional features are approximated by a linear combination of their Gaussian functions. Second, the feature kernel matrix is transformed into two latent variables through entropy component analysis (ECA). With the bikernel mapping and ECA, outliers are depicted away from the inliers in two-dimensional (2D) scatter plots. Then, the squared Mahalanobis distance is used as the fault detection index, whose confidence boundary is represented as an ellipse in the 2D map. The performance of the proposed method is demonstrated through two case studies on the Tennessee Eastman process as well as a real recombinant human granulocyte colony-stimulating factor production process.

Tick-borne encephalitis (TBE) is an important zoonotic viral disease transmitted by ticks. In recent decades, global climate change has increased human exposure to ticks, and mortality rates have gradually risen. Effective vaccines are essential for controlling TBE as specific antiviral treatment is unavailable. Vaccine candidates based on virus-like particles (VLPs) have previously been demonstrated to be efficient in eliciting excellent immune responses against influenza virus and SARS-CoV-2. Here, we constructed TBE virus (TBEV) VLPs containing the envelope and membrane proteins derived from the Far Eastern TBEV strain (WH2012) using an insect cell-baculovirus expression system. Induction of immune responses was investigated in mice following intramuscular injection with the TBEV VLPs vaccine candidates formulated of Poly(I:C) & Montanide ISA 201VG combination adjuvants. Mice produced memory T-cells and serum-specific IgG antibodies that averaged up to 1:104.6and remained at 1:104(mean) for 24 weeks after three immunizations. TBEV VLPs vaccine was able to provide long-term antibody protection against TBEV, making it a promising subunit vaccine candidate for this disease.

Didemnins are a class of cyclic depsipeptides derived from sea tunicates that exhibit potent anticancer, antiviral, and immunosuppressive properties. Although certain Tistrellaspecies can produce didemnins, their complete biosynthetic potential remains largely unexplored. In this study, we utilize feature-based molecular networking to analyze the metabolomics of Tistrella mobilisand Tistrella bauzanensis, focusing on the production of didemnin natural products. In addition to didemnin B, we identify nordidemnin B and [hysp2]didemnin B, as well as several minor didemnin analogs. Heterologous expression of the didemnin biosynthetic gene cluster in a Streptomyceshost results in the production of only didemnin B and nordidemnin B in limited quantities. Isotope-labeling studies reveal that the substrate promiscuity of the adenylation domains during biosynthesis leads to the accumulation of nordidemnin B and [hysp2]didemnin B. Additionally, precursor-directed biosynthesis is applied to generate eight novel didemnin derivatives by supplementing the culture with structurally related amino acids. Furthermore, we increased the titers of nordidemnin B and [hysp2]didemnin B by supplementing the fermentation medium with l-valine and l-isoleucine, respectively. Finally, both compounds undergo side-chain oxidation to enhance their biological activity, with their anticancer properties found to be as potent as plitidepsin.

A variety of natural substances including both volatile organic compounds and water-soluble compounds play a significant role in the chemotactic behaviors of the model nematode Caenorhabditis elegans. We observed chemotactic behaviors of C. eleganswith respect to response to attractants produced by nematode parasitic fungus Stropharia rugosoannulata, which were partially induced by specific amino acids. The results of gas chromatography-mass spectrometer analysis suggested that 1-octen-3-ol was produced and benzaldehyde concentrations increased when L-phenylalanine was added to water agar plate. Similarly, the addition of L-tryptophan to the medium induced the production of benzaldehyde, 1-octen-3-ol and indole. The presence of L-phenylalanine and L-tryptophan increased the attraction of C. elegansto S. rugosoannulata. With attraction increased, nematode mortality increased more than 6 times higher.

The glucose transporter 1 (GLUT1) protein is involved in the basal-level absorption of glucose in tumor cells. Inhibiting GLUT1 decreases tumor cell proliferation and induces tumor cell damage. Natural GLUT1 inhibitors have been studied only to a small extent, and the structures of known natural GLUT1 inhibitors are limited to a few classes of natural products. Therefore, discovering and researching other natural GLUT1 inhibitors with novel scaffolds are essential. Physalis angulataL. var. villosais a plant known as Mao-Ku-Zhi (MKZ). Withanolides are the main phytochemical components of MKZ. MKZ extracts and the components of MKZ exhibited antitumor activity in recent pharmacological studies. However, the antitumor-active components of MKZ and their molecular mechanisms remain unknown. A cell membrane-biomimetic nanoplatform (CM@Fe3O4/MIL-101) was used for target separation of potential GLUT1 inhibitors from MKZ. A new withanolide, physagulide Y (2), together with six known withanolides (1, 3–7), was identified as a potential GLUT1 inhibitor. Physagulide Y was the most potent GLUT1 inhibitor, and its antitumor activity and possible mechanism of action were explored in MCF-7 human cancer cells. These findings advance the development of technologies for the targeted separation of natural products and identify a new molecular framework for the investigation of natural GLUT1 inhibitors.

Apoptosis mediated by reactive oxygen species (ROS) has emerged as a promising therapeutic strategy for tumors. However, the overexpression of NAD(P)H:quinone oxidoreductase 1 (NQO1) protein restricted ROS production through a negative feedback pathway in tumor cells, promoting tumor progression, and weakening the effect of drug therapy. Here, a PROTACs nanodrug delivery system (PN) was constructed to increase ROS generation by degrading the NQO1 protein. Specifically, a PROTAC (proteolytic targeting chimera) molecule DQ was designed and synthesized. Then DQ and withaferin A (WA, an inducer of ROS) were loaded into PNs. DQ degraded the overexpressed NQO1 protein in tumor cells through a protein ubiquitination degradation pathway, thereby weakening the antioxidant capacity of tumor cells. Meanwhile, the reduction of NQO1 could inhibit the negative feedback effect of ROS production, thus increasing ROS generation. It has been demonstrated that PNs can significantly increase ROS production and possess potent antitumor properties in vitroand in vivo.This nanoplatform may offer an alternative approach to treating tumors with NQO1 overexpression.

The investigations have shown that the hot and dense matter created in p-pcollisions at high energies have the similar collective motion as that formed in nucleus-nucleus collisions. The best tool for describing collective motion is relativistic hydrodynamics. In this paper, in the framework of the combined model of unified hydrodynamics + leading particles, we discuss the pseudorapidity distributions of charged particles produced in p-pcollisions. The rapidity distributions of charged particles frozen out from the fluid expanding according to unified hydrodynamics can be worked out exactly. The rapidity distributions of leading particles are assumed possessing the Gaussian form. It can be seen that the theoretical model works well for p-pcollisions in the whole available energy region from 23.6 to 7000 GeV.

By using the revised Landau hydrodynamic model and taking into account the effect of leading particles, we discuss the pseudorapidity distributions of the charged particles produced in high-energy heavy-ion collisions. The leading particles are assumed to have the rapidity distributions with Gaussian forms with the normalization constant being equal to the number of participants, which can be figured out in theory. The results from the revised Landau hydrodynamic model, together with the contributions from leading particles, were found to be consistent with the experimental data obtained by the PHOBOS Collaboration on RHIC (Relativistic Heavy Ion Collider) at BNL (Brookhaven National Laboratory) in different centrality Cu+Cu and Au+Au collisions at high energies.

An ultrasensitive immunoassay method was developed based on the amplified inhibition of the electrochemical signal of graphene–thionine nanocomposites. The graphene–thionine nanocomposite was prepared by one-step reduction of graphene oxide in thionine solution and used to modify a glassy carbon electrode. The immunosensor was prepared by stepwise assembly of gold nanoparticles (Au NPs) and a capture antibody at this nanocomposite modified electrode. The thionine on the immunosensor surface exhibited a good electrochemical signal which was further promoted by the presence of Au NPs. After a sandwich immunoreaction, the current response of the immunosensor decreased due to the formation of a dielectric antibody–antigen immunocomplex on its surface. This current decrease could be further amplified by the captured antibody conjugated silica nanosphere with low electric conductivity. Based on this amplified signal inhibition mechanism, a novel detection strategy for the ultrasensitive electrochemical immunoassay was developed. Using human IgG as a model protein, a wide linear range in four orders of magnitude and a low detection limit down to 7 pg mL−1were achieved. In addition, the immunosensor has low cost, satisfactory reproducibility and stability, and acceptable reliability, thus providing promising potential for clinical applications.

ABSTRACTCryptosporidium parvumis an opportunistic pathogen in AIDS patients. It is an intracellular but extracytoplasmic parasite residing in a host cell-derived parasitophorous vacuole. It is still poorly understood how this parasite interacts with host cells. We observed that expression of the integrin a2 (ITGA2) gene in host cells was significantly upregulated upon C. parvuminfection, and a higher level of ITGA2 protein was present in the parasite infection sites. The infection could be reduced by the treatment of antibodies against ITGA2 and integrin ß1 (ITGB1) subunits, as well as by type I collagen (an integrin a2ß1 ligand). We also generated stable knockdown of ITGA2 gene expression in HCT-8 cells and observed consistent reduction of parasite infection in these knockdown cells. Collectively, our evidence indicates that host cell ITGA2 might be involved in interacting with Cryptosporidiumduring infection, probably acting as part of the regulatory elements upstream of the reported recruiting and reorganization of F actin at the infection sites.

Cryptosporidium parvum is an opportunistic pathogen in AIDS patients. It is an intracellular but extracytoplasmic parasite residing in a host cell-derived parasitophorous vacuole. It is still poorly understood how this parasite interacts with host cells. We observed that expression of the integrin α2 (ITGA2) gene in host cells was significantly upregulated upon C. parvum infection, and a higher level of ITGA2 protein was present in the parasite infection sites. The infection could be reduced by the treatment of antibodies against ITGA2 and integrin β1 (ITGB1) subunits, as well as by type I collagen (an integrin α2β1 ligand). We also generated stable knockdown of ITGA2 gene expression in HCT-8 cells and observed consistent reduction of parasite infection in these knockdown cells. Collectively, our evidence indicates that host cell ITGA2 might be involved in interacting with Cryptosporidium during infection, probably acting as part of the regulatory elements upstream of the reported recruiting and reorganization of F actin at the infection sites.

An on‐column preconcentration technique, pH‐mediated acid stacking, was used in this study to improve the sensitivity of MEKC‐UV analysis of IgG in human serum. Various parameters affecting pH‐mediated acid stacking were optimized systematically. To eliminate the matrix interferences of human serum and to combine the sample pretreatment procedure with the detection methodology, silica‐coated Fe3O4magnetic nanoparticles modified with N‐(2‐aminoethyl)‐3‐aminopropyl‐trimethoxysilane were prepared and employed as solid phase extraction adsorbent to remove the abundant HSA from human serum. HSA was quantitatively removed by silica‐coated Fe3O4magnetic nanoparticles modified with N‐(2‐aminoethyl)‐3‐aminopropyl‐trimethoxysilanes without retaining IgG at pH 9.3. Under the optimum conditions, the sensitivity of IgG was improved 40.3‐fold using a 100 s electrokinetic injection as compared with a 6 s hydrodynamic injection. The detection limit of IgG was found to be 0.1 mg/L, and the proposed method was successfully applied for the determination of IgG in human serum with satisfactory results.

DYF-1 is a highly conserved protein. Our results demonstrate that DYF-1 is a canonical subunit of IFT particle complex B and strongly support the hypothesis that the IFT machinery has species- and tissue-specific variations with functional ramifications.

DYF-1 is a highly conserved protein essential for ciliogenesis in several model organisms. In Caenorhabditis elegans, DYF-1 serves as an essential activator for an anterograde motor OSM-3 of intraflagellar transport (IFT), the ciliogenesis-required motility that mediates the transport of flagellar precursors and removal of turnover products. In zebrafish and Tetrahymena DYF-1 influences the cilia tubulin posttranslational modification and may have more ubiquitous function in ciliogenesis than OSM-3. Here we address how DYF-1 biochemically interacts with the IFT machinery by using the model organism Chlamydomonas reinhardtii, in which the anterograde IFT does not depend on OSM-3. Our results show that this protein is a stoichiometric component of the IFT particle complex B and interacts directly with complex B subunit IFT46. In concurrence with the established IFT protein nomenclature, DYF-1 is also named IFT70 after the apparent size of the protein. IFT70/CrDYF-1 is essential for the function of IFT in building the flagellum because the flagella of IFT70/CrDYF-1–depleted cells were greatly shortened. Together, these results demonstrate that IFT70/CrDYF-1 is a canonical subunit of IFT particle complex B and strongly support the hypothesis that the IFT machinery has species- and tissue-specific variations with functional ramifications.

We report the construction of titania contained opal and inverse opal structures by using colloidal crystals as templates which were self assembled from poly(allylamine hydrochloride) (PAH)/poly(acrylic acid) (PAA) multilayer film coated polystyrene (PS) particles. By infiltrating a titania precursor titanium (IV) bis (ammonium lactato) dihydroxide (TALH) into the polyelectrolyte (PE) multilayer film followed by calcination at different temperatures, PE/TiO2 composite opal or inverse opal structures were obtained. The thickness of the titania coating on colloidal crystals or the wall thickness of titania inverse opals could be controlled by varying the coating thickness of the PE film on PS particles during the layer-by-layer (LbL) deposition process. The crystalline phase of titania inverse opals was determined by the heating temperature. However, titania inverse opals with pure rutile phase lost their ordered structures due to the formation of large rigid rutile titania crystals during the phase transfer process. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), reflectance spectroscopy and X-ray diffraction were employed to characterize the formed structures and titania crystal phases.

The effects of gas space time on the product distribution in noncatalytic gas-phase methane oxidation and in the combination reaction of noncatalytic and catalytic oxidative coupling of methane (OCM) over Mn/Na2WO4/SiO2catalyst were studied. For the gas-phase reaction, methane and oxygen conversions and syngas selectivity increase drastically with increasing gas space time (tg) from 6.2 to 7.7 s; however, the selectivity of C2hydrocarbons decreases sharply in this range and the concentration of C2H4in the producing mixture is much lower than that of CO and H2. For the combination reaction, there is a minimum of methane conversion and C2hydrocarbon selectivity with tgincreasing from 3 to 5 s resulting from the variation of the mixture composition reaching the catalyst bed. The dilution of the catalyst bed with silica chips in the combination reaction partially restricts the sequential oxidation of products and raises the selectivities of ethylene and hydrogen. Surface enrichment of Na, W, and Mn species is observed on the catalysts used both in the sole catalytic OCM and in the combination reaction. The combination reaction makes the enrichment of Na and W species more evident, and the aggregation of Mn species less obvious, than the OCM reaction.

Abstract: In this paper, we present the optical properties and the platforms on fluorescent quantum dots for biological labeling, biomedical engineering and biosensor in molecular imaging. Quantum dots possess several properties that make them very attractive for fluorescent tagging: broad excitation spectrum, narrow emission spectrum, precise tunability of their emission peak, longer fluorescence lifetime than organic fluorophores and negligible photobleaching. We describe how to take such advantages of quantum dots to develop the technology and employ it to build assay platforms. Finally, ultrasensitivity, multicolor, and multiplexing of the technology of semiconductor quantum dots open up promising and interesting possibilities for bioassay platform.

The promoter of the pumpkin (Cucurbita moschata) PP2gene (designated NP) was isolated from the restriction enzyme-digested genomic DNA pool by genome walking and its activity and phloem specificity were examined in transgenic tobacco plants by using GUS as a reporter. Deletion analysis of the promoter revealed that the 473-bp fragment (−465 to +8 relative to the transcription start site; designated as NPII) exhibited similar activity as the full-length NP promoter and retained its phloem specificity. Furthermore, the sequence from −465 to −171 was shown to contain positive regulatory cis-elements for the promoter activity. An enhanced NP promoter was constructed by duplicating the sequence −465 to −85, and its activity in phloem tissue was shown to be higher than that of the Commelina Yellow Mottle Virus (CoYMV) promoter or a chimeric promoter consisting of the double enhancer sequence from the Cauliflower Mosaic Virus (CaMV) 35S promoter fused upstream to the NPII fragment.

Mesostructured cellular foam (MCF) materials were synthesized by microemulsion followed by functionalization with glucose or glutaraldehyde. Successful surface modification was confirmed by Fourier transform infrared, X-ray small-angle diffraction, and nitrogen sorption measurements. The effect of surface chemistry of MCF on the loading and release of streptomycin sulfate was studied in detail. Results indicated that grafting with either glucose or glutaraldehyde cannot only increase the loading amount of drug from 5% to 25% but also change the drug release profile significantly. This work provided an excellent example of controlling drug release by varying the surface chemistry of the materials.

Novel antiparasitic activity was observed for the antifungal occidiofungin. It efficaciously and irreversibly inhibited the zoonotic enteric parasite Cryptosporidium parvumin vitrowith limited cytotoxicity (50% effective concentration [EC50] = 120 nM versus 50% cytotoxic concentration [TC50] = 988 nM), and its application disrupted the parasite morphology. This study expands the spectrum of activity of a glycolipopeptide named occidiofungin.

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