Maximum Correntropy Filtering for Complex Networks With Uncertain Dynamical Bias: Enabling Componentwise Event-Triggered Transmission.

This article is concerned with the maximum correntropy filtering (MCF) problem for a class of nonlinear complex networks subject to non-Gaussian noises and uncertain dynamical bias. With aim to utilize the constrained network bandwidth and energy resources in an efficient way, a componentwise dynamic event-triggered transmission (DETT) protocol is adopted to ensure that each sensor component independently determines the time instant for transmitting data according to the individual triggering condition. The principal purpose of the addressed problem is to put forward a dynamic event-triggered recursive filtering scheme under the maximum correntropy criterion, such that the effects of the non-Gaussian noises can be attenuated. In doing so, a novel correntropy-based performance index (CBPI) is first proposed to reflect the impacts from the componentwise DETT mechanism, the system nonlinearity, and the uncertain dynamical bias. The CBPI is parameterized by deriving upper bounds on the one-step prediction error covariance and the equivalent noise covariance. Subsequently, the filter gain matrix is designed by means of maximizing the proposed CBPI. Finally, an illustrative example is provided to substantiate the feasibility and effectiveness of the developed MCF scheme.

Metabolic Engineering of Escherichia coli for High-Level Production of Lacto-N-neotetraose and Lacto-N-tetraose.

Lacto-N-neotetraose (LNnT) and lacto-N-tetraose (LNT) are important oligosaccharides found in breast milk and are commonly used as nutritional supplements in infant formula. We used metabolic engineering techniques to optimize the modified Escherichia coli BL21 star (DE3) strain for efficient synthesis of LNnT and LNT using ß-1,4-galactosyltransferase (HpgalT) from Helicobacter pylori and ß-1,3-galactosyltransferase (SewbdO) from Salmonella enterica subsp. salamae serovar, respectively. Further, we optimized the expression of three key genes, lgtA, galE, and HpgalT (SewbdO), to synthesize LNnT or LNT and deleted several genes (ugd, ushA, agp, wcaJ, otsA, and wcaC) to block competition in the UDP-galactose synthesis pathway. The optimized strain produced LNnT or LNT with a titer of 22.07 or 48.41 g/L, respectively, in a supplemented batch culture, producing 0.41 or 0.73 g/L/h, respectively. The strategies used in this study contribute to the development of cell factories for high-level LNnT and LNT and their derivatives.

The Electronic Properties of Cadmium Naphthalene Diimide Coordination Complex.

The computational simulations for electronic properties of cadmium (Cd) coordinated L-alanine NDI ligand (H2-l-ala NDI) based complex are the focus of this research. For the first time, the Cd-NDI complex (monomer) has been produced using water as the solvent; this is a new approach to synthesizing the Cd-NDI complex that has not been reported yet. Along with crystallography and Hirsch field analysis, CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets were used, and in-depth characterisation of the Cd-NDI complex by following DFT and TD-DFT hypothetical simulations. Hyperpolarizabilities, frontier molecular orbitals (FMOs), the density of states (DOS), dipole moment (µ), electron density distribution map (EDDM), transition density matrix (TDM), molecular electrostatic potential (MEP), electron-hole analysis (EHA), and electrical conductivity (σ) have all been studied regarding the Cd-NDI complex. The vibrational frequencies and types of interaction are studied using infrared (IR) and non-covalent interaction (NCI) analysis with iso-surface. In comparison to the Cd-NDI complex with 2.61, 2.42 eV Eg (using CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets, respectively) and 376 nm λmax, (in case of B3LYP/LANL2MB λmax is higher), H2-l-ala NDI have 3.387 eV Eg and 375 nm λmax, metal-ligand coordination in complex dramatically altered charge transfer properties, such as narrowing band gap (Eg). Based on the electronic properties analysis of Cd-NDI complex, it is predicted that the Cd-NDI complex will have a spectacular (nonlinear optical) NLO response. The Cd-NDI complex is discovered to be advantageous for the creation of future nanoscale devices due to the harmony between the Cd metal and H2-l-ala NDI, in addition to their influences on NLO characteristics.

The Full Cytosine-Cytosine Base Paring: Self-Assembly and Crystal Structure.

The synthesis of self-assembly systems that can mimic partial biological behaviours require ingenious and delicate design. For decades, scientists are committed to exploring new base pairing patterns using hydrogen bonds directed self-assembly of nucleotides. A fundamental question is the adaptive circumstance of the recognition between base pairs, namely, how solvent conditions affect the domain of base pairs. Towards this question, three nucleotide complexes based on 2'-deoxycytidine-5'-monophosphate (dCMP) and cytidine-5'-monophosphate (CMP) were synthesized in different solvents and pH values, and an unusual cytosine-cytosine base paring pattern (named full C : C base pairing) has been successfully obtained. Systematic single crystal analysis and 1 H NMR titration spectra have been performed to explore factors influencing the formation of base paring patterns. Moreover, supramolecular chirality of three complexes were studied using circular dichroism (CD) spectroscopy in solution and solid-state combined with crystal structure analysis.

Preferential Enrichment of Enantiomer from Amino Acid Schiff Bases by Coordination Interaction and Crystallization.

In this paper, preferential enrichment (PE) is described for three pairs of novel amino acid Schiff base Cu(II)/Cu(I) complexes. Single crystal X-ray diffraction indicated that 1-S/R are one-dimensional coordination polymers (CPs) with helical structures, and 2-S/R and 3-S/R are one-dimensional CPs with auxiliary ligands. By tuning the pH, the solvent and second ligands, the 1-S/R, 3-S/R underwent polymorphic transitions, resulting in enantioselective liberation of excess enantiomers into solution, until the deposited crystals were slightly enriched with the opposite enantiomer, thereby successfully exhibiting PE. However, under the effects of Cu(II), the solvent and low pH, 2-S/R did not exhibit PE and resulted in enrichment of racemic compounds, which was attributed to amino acid Schiff base chiral complex mechanisms of PE. The three pairs of Cu complex structures were characterized by UV-vis, MS and X-ray photoelectron spectroscopy (XPS). All chiral properties were studied by circular dichroism (CD) in the solid and liquid.

Coordination Patterns of the Diphosphate in IDP Coordination Complexes: Crystal Structure and Chirality.

The knowledge of accurate geometrical parameters from X-ray diffraction studies in the solid state of metal nucleotide is very important for understanding the relationship between structures and properties, including biochemical processes and even enzyme-metal-substrate interactions. The research is also very necessary to precisely and controllably design the functional materials. Here, seven types of coordination polymers of inosine 5'-diphosphate nucleotide (IDP) with transition metals, {[Zn(HIDP)(azpy)(H2O)2]·4H2O}n (1), {[Cd2(IDP)2(bpda)2]·[Cd(H2O)6]·11H2O}n (2), {[Cd3(IDP)2(4,4'-bipy)2(H2O)3]·6H2O}n (3), {[Cd2(IDP)2(bpe)2(H2O)2]·(H2bpe)·26H2O}n (4), {[Cu3(IDP)2(azpy)2(H2O)5]·5H2O}n (5), {[Cu3(IDP)2(bpe)2(H2O)5]·9H2O}n (6), and {[Co(HIDP)(azpy)(H2O)2]·7H2O}n (7) [4,4'-bipy = 4,4'-bipyridine, azpy = 4,4'-azopyridine, bpe = 1,2-bis(4-pyridyl)ethene, and bpda = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene], were designed, synthesized, and firmly characterized using single-crystal X-ray diffraction. The coordination patterns of the diphosphate group of IDP in these complexes were studied by crystallographic analysis, namely, open, close, and open-close hybrid types. We have investigated the diverse coordination patterns of the diphosphate group and its spatial relationship relative to the pentose ring on the basis of two conformational parameters, the pseudorotation phase angle and the degree of puckering. Crystallographic studies clearly reveal the correlation between the backbone torsion angle (ω' and φ) of the sugar-diphosphate and the conformational preference of the pentose ring, i.e., the signs of the backbone torsion angles ω' and φ are both plus (+) or minus (-), the conformation of the pentose ring is envelope form (E), while when one of the two signs is plus (+) and the other is minus (-), the pentose ring is in the twist form (T). This is the first time elucidation of the coordination pattern of diphosphate relative to the conformation of the pentose ring in nucleotide metal complexes, which are different from the other inorganic or organic diphosphate compounds. The chirality of these coordination polymers was examined by combining solid-state circular dichroism spectroscopy measurements with the explanation of their crystal structures. The results presented in this paper are very important for understanding their nucleotide coordination chemistry, their supramolecular chemistry, and even their biochemistry.

Effects of Biocontrol Agents Application on Soil Bacterial Community and the Quality of Tobacco.

In this study, to evaluate the effect of different biocontrol agents (BCAs) on the soil bacterial community, we investigated the effects of Bacillus amyloliquefaciens, synthetic bacterial community (Aspergillus niger:Bacillus subtilis:Bacillus licheniformis:Streptomyces microflavus = 3:3:3:1, SynCom), and BCAs combined with lime-nitrogen on soil bacterial community by utilizing 16S rRNA sequencing technology. The sequencing shows that BCAs application can improve the value of Shannon and Sobs index of bacterial community during tobacco rosette and vigorous growing period. With the growth of tobacco, the effect of BCAs on the composition and difference of soil bacterial community structure becomes more and more obvious. In terms of average relative richness, the top six phyla of soil bacterial community are Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria, Gemmatimonadetes, and Bacteroidetes. Bacillus amyloliquefaciens application can increase the relative richness of Proteobacteria and Bacteroidetes. And the combination between BCAs and lime-nitrogen can increase the relative richness of Gemmatimonadetes and Bacteroidetes. The SynCom also can increase the relative richness of Bacteroidetes, whereas it decreases the relative richness of Acidobacteria. Proteobacteria, Acidobacteria, Gemmatimonadetes, and Bacteroidetes showing an extremely significant correlation with pH and exchangeable magnesium (EMg). BCAs application can improve the tobacco yield, effective leaves, and reducing sugar content that also has extremely significant positive correlation with pH and EMg. In conclusion, the results of our field experiments clearly show that BCAs application can significantly affect the soil pH and EMg by changing most of the dominant soil bacterial species. The richness of Bacteroidetes can serve as an indicator of the changes in soil pH and EMg caused by BCAs application.

Particle-Filter-Based State Estimation for Delayed Artificial Neural Networks: When Probabilistic Saturation Constraints Meet Redundant Channels.

In this brief, the state estimation problem is investigated for a class of randomly delayed artificial neural networks (ANNs) subject to probabilistic saturation constraints (PSCs) and non-Gaussian noises under the redundant communication channels. A series of mutually independent Bernoulli distributed white sequences are introduced to govern the random occurrence of the time delays, the saturation constraints, and the transmission channel failures. A comprehensive redundant-channel-based communication mechanism is constructed to attenuate the phenomenon of packet dropouts so as to enhance the quality of data transmission. To compensate for the influence of randomly occurring time delays, the corresponding occurrence probability is exploited in the process of particle generation. In addition, an explicit expression of the likelihood function is established based on the statistical information to account for the impact of PSCs and redundant channels. By virtue of the modified operations of particle propagation and weight update, a particle-filter-based state estimation algorithm is proposed with mild restriction on the system type. Finally, an illustrative example with Monte Carlo simulations is provided to demonstrate the effectiveness of the developed state estimation scheme.

Efficacy comparison of immune treating strategies for NSCLC patients with negative PD-L1 expression.

BACKGROUND: We intended to compare and grade the proposed immune treating strategies for non-small cell lung cancer (NSCLC) with negative Programmed Cell Death Ligand 1(PD-L1). METHODS: We compared the efficacy of single immune checkpoint inhibitor (ICI), single ICI plus chemotherapy, and doublet ICIs with chemotherapy alone, as well as single ICI plus radiotherapy with single ICI for negative PD-L1 (<1%) NSCLC patients. Hazard Ratio (HR) and 95% confidence interval (CI) of progression-free survival (PFS) and overall survival (OS) were used as outcomes. RESULTS: We included 23 randomized control trials with 4665 patients. Compared with chemotherapy alone, single ICI, single ICI plus chemotherapy and doublet ICIs all showed a better OS (0.84 [0.71, 0.99] ; 0.77 [0.69, 0.85] ; 0.64 [0.53, 0.77])), while single ICI plus chemotherapy and doublet ICIs showed a better PFS (0.68 [0.61, 0.75] ; 0.69 [0.56, 0.85]). Additionally, single ICI plus radiotherapy obtained a greater pooled PFS (0.49 [0.28-0.87]) than single ICI. CONCLUSIONS: Both single ICI plus chemotherapy and doublet ICIs were probably better treatment decisions than chemotherapy alone for negative PD-L1 NSCLC patients. Also, single ICI plus radiotherapy carved out a new strategy.

Novel carboxymethyl chitosan/N-acetylneuraminic acid hydrogel for the protection of Pediococcus pentosaceus.

In this study, carboxymethyl chitosan (CMCS) and N-acetylneuraminic acid (NeuAc) were used to develop C-NeuAc hydrogels to encapsulate Pediococcus pentosaceus QK-1. The mechanical properties, thermal stability, in vitro degradation, and pH sensitivity of the hydrogel were evaluated. The C-NeuAc concentration required for optimal hydrogel performance was 3% (w/v). Hydrogel swelling behaviour was effectively assessed by Fickian diffusion and Schott's second-order kinetic models. The hydrogel demonstrated excellent biocompatibility and low in vitro cytotoxicity. An in vitro assay revealed that the viability of Pediococcus pentosaceus QK-1 in C-NeuAc had decreased by only 1.41 log (CFU/ mL) after exposure to simulated acidic gastric fluid. Moreover, the survival rate of the encapsulated and free Pediococcus pentosaceus QK-1 cells were 80.1% and virtually zero, respectively, after passage through the gastrointestinal tract. It was empirically determined that low temperature and freeze-drying were the ideal condition and method to ensure storage longevity of the hydrogel-encapsulated probiotic. Hence, C-NeuAc hydrogel is highly desirable as a food-grade probiotic delivery vehicle.

Conformation Locking of the Pentose Ring in Nucleotide Monophosphate Coordination Polymers via π-π Stacking and Metal-Ion Coordination.

The conformation of the pentose ring in nucleotides is extremely important and a basic problem in biochemistry and pharmaceutical chemistry. In this study, we used a strategy to regulate the conformation of pentose rings of nucleotides via the synergistic effect of metal-ion coordination and π-π stacking. Seven types of coordination complexes were developed and characterized using Fourier transform infrared spectroscopy, elemental analysis, thermogravimetric analysis, powder X-ray diffraction, ultraviolet-visible spectroscopy, 1H nuclear magnetic resonance spectroscopy, electrospray ionization mass spectrometry, and single-crystal X-ray diffraction. On the basis of two conformational parameters obtained from single-crystal structure analysis, i.e., the pseudorotation phase angle and degree of puckering, the exact conformation of the furanose ring in these coordination polymers was unequivocally determined. Crystallographic studies demonstrate that a short bridging ligand (4,4'-bipyridine) is conducive to the formation of a twist form, and long auxiliary ligands [1,2-bis(4-pyridyl)ethene and 4,4'-azopyridine] induce the formation of an envelope conformation. However, the longest auxiliary ligands [1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene] cannot limit the flexibility of a nucleotide. Our results demonstrated that the proposed strategy is universal and controllable. Moreover, the chirality of these coordination polymers was examined by combining the explanation of their crystal structures with solid-state circular dichroism spectroscopy measurements.

Distributed Robust Optimization Algorithms Over Uncertain Network Graphs.

This article investigates the robustness issues of a set of distributed optimization algorithms, which aim to approach the optimal solution to a sum of local cost functions over an uncertain network. The uncertain communication network consists of transmission channels perturbed by additive deterministic uncertainties, which can describe quantization and transmission errors. A new robust initialization-free algorithm is proposed for the distributed optimization problem of multiple Euler-Lagrange systems, and the explicit relationship of the feedback gain of the algorithm, the communication topology, the properties of the cost function, and the radius of the channel uncertainties is established in order to reach the optimal solution. This result provides a sufficient condition for the selection of the feedback gain when the uncertainty size is less than the unity. As a special case, we discuss the impact of communication uncertainties on the distributed optimization algorithms for first-order integrator networks.

The Research of G-Motif Construction and Chirality in Deoxyguanosine Monophosphate Nucleotide Complexes.

A detailed understanding of the mismatched base-pairing interactions in DNA will help reveal genetic diseases and provide a theoretical basis for the development of targeted drugs. Here, we utilized mononucleotide fragment to simulate mismatch DNA interactions in a local hydrophobic microenvironment. The bipyridyl-type bridging ligands were employed as a mild stabilizer to stabilize the GG mismatch containing complexes, allowing mismatch to be visualized based on X-ray crystallography. Five single crystals of 2'-deoxyguanosine-5'-monophosphate (dGMP) metal complexes were designed and obtained via the process of self-assembly. Crystallographic studies clearly reveal the details of the supramolecular interaction between mononucleotides and guest intercalators. A novel guanine-guanine base mismatch pattern with unusual (high anti)-(high anti) type of arrangement around the glycosidic angle conformations was successfully constructed. The solution state 1H-NMR, ESI-MS spectrum studies, and UV titration experiments emphasize the robustness of this g-motif in solution. Additionally, we combined the methods of single-crystal and solution-, solid-state CD spectrum together to discuss the chirality of the complexes. The complexes containing the g-motif structure, which reduces the energy of the system, following the solid-state CD signals, generally move in the long-wave direction. These results provided a new mismatched base pairing, that is g-motif. The interaction mode and full characterizations of g-motif will contribute to the study of the mismatched DNA interaction.

Enhanced bioproduction of fucosylated oligosaccharide 3-fucosyllactose in engineered Escherichia coli with an improved de novo pathway.

3-fucosyllactose (3-FL) and 2'-fucosyllactose (2'-FL), are two important fucosylated oligosaccharides in human milk. Extensive studies on 2'-FL enabled its official approval for use in infant formula. However, development of 3-FL has been somewhat sluggish due to its low content in human milk and poor yield in enlarged production. Here, an α-1,3-fucosyltransferase mutant was introduced into an engineered Escherichia coli (E. coli) capable of producing GDP-L-fucose, leading to a promising 3-FL titer in a 5.0-L bioreactor. To increase the availability of cofactors (NADPH and GTP) for optimized 3-FL production, zwf, pntAB, and gsk genes were successively overexpressed, finally resulting in a higher 3-FL level with a titer of 35.72 g/L and a yield of 0.82 mol 3-FL/mol lactose. Unexpectedly, the deletion of pfkA gene led to a much lower performance of 3-FL production than the control strain. Still, our strategy achieved the highest 3-FL level in E. coli to date.

LncRNA HOXA-AS3 Promotes the Progression of Pulmonary Arterial Hypertension through Mediation of miR-675-3p/PDE5A Axis.

Pulmonary arterial hypertension (PAH) seriously threatens the elder people. Long non-coding RNAs (lncRNAs) are involved in multiple diseases. However, the study of the lncRNAs in the occurrence of PAH is just beginning. For this, we sought to explore the biological function of lncRNA HOXA cluster antisense RNA 3 (HOXA-AS3) in PAH. Hypoxia (HYP) was used to mimic in vitro model of PAH. Gene and protein expressions in cells were detected by q-PCR and Western blotting, respectively. In addition, cell proliferation and viability were tested by CCK-8 and MTT assay. Cell apoptosis was measured by flow cytometry. Wound healing was used to detect cell migration. Furthermore, the connection of HOXA-AS3, miR-675-3p, and phosphodiesterase 5A (PDE5A) was verified by dual-luciferase report assay. HOXA-AS3 and PDE5A were upregulated in human pulmonary artery smooth muscle cells (HPASMCs) in the presence of HYP, while miR-675-3p was downregulated. Moreover, knockdown of HOXA-AS3 suppressed the growth and migration of HPASMCs, but induced the apoptosis. Overexpression of miR-675-3p achieved the same effect. MiR-675-3p inhibitor or overexpression of PDE5A notably reversed the inhibitory effect of HOXA-AS3 knockdown on PAH. Finally, HOXA-AS3 could sponge miR-675-3p, and PDE5A was directly targeted by miR-675-3p. HOXA-AS3 increased the development of PAH via regulation of miR-675-3p/PDE5 axis, which could be the potential biomarker for treatment of PAH.

Distributed Edge-Based Event-Triggered Formation Control.

This paper considers the formation control problem for general linear networked agents constrained with event-triggered communications. We propose four kinds of edge-based event-triggered protocols, each of which can be used to achieve given formation structures and eliminate the unexpected Zeno behavior. Since the whole protocols are designed according to sampled information at event instants rather than real-time information, these protocols efficiently avoid continuous communications, reduce the bandwidth need of communication, and decrease the energy consuming. The distributed static state feedback edge-based event-triggered protocol or the adaptive one is applicable for the occasions with available states. Different from the state feedback protocols, users can choose the distributed static output feedback edge-based event-triggered protocol or the adaptive one no matter whether agents' states are available or not. It is worth emphasizing that the adaptive state (or output) feedback event-triggered protocol requires no global information of the network topology and can be used in a fully distributed and scalable manner. Finally, numerical examples on formation control are offered to testify the feasibility of the proposed protocols.

Erratum: Event-Triggered Consensus of Homogeneous and Heterogeneous Multiagent Systems With Jointly Connected Switching Topologies.

Presents corrections to the above named paper.

Multi-Enzymatic Cascade One-Pot Biosynthesis of 3'-Sialyllactose Using Engineered Escherichia coli.

Among the human milk oligosaccharides (HMOs), one of the most abundant oligosaccharides and has great benefits for human health is 3'-sialyllactose (3'-SL). Given its important physiological functions and the lack of cost-effective production processes, we constructed an in vitro multi-enzymatic cofactor recycling system for the biosynthesis of 3'-SL from a low-cost substrate. First, we constructed the biosynthetic pathway and increased the solubility of cytidine monophosphate kinase (CMK) with chaperones. We subsequently identified that ß-galactosidase (lacZ) affects the yield of 3'-SL, and hence with the lacZ gene knocked out, a 3.3-fold increase in the production of 3'-SL was observed. Further, temperature, pH, polyphosphate concentration, and concentration of divalent metal ions for 3'-SL production were optimized. Finally, an efficient biotransformation system was established under the optimized conditions. The maximum production of 3'-SL reached 38.7 mM, and a molar yield of 97.1% from N-acetylneuraminic acid (NeuAc, sialic acid, SA) was obtained. The results demonstrate that the multi-enzymatic cascade biosynthetic pathway with cofactor regeneration holds promise as an industrial strategy for producing 3'-SL.

Resection of a Giant Bronchogenic Cyst in the Left Atrium.

A bronchogenic cyst in the left atrium is rare. We report the case of a 17-year-old male patient who was admitted to the emergency department because of severe chest pain and dyspnea. He was diagnosed using echocardiography and computed tomography, which revealed a huge cardiac tumour in the dome of the left atrium. He was surgically treated with tumour enucleation. The resultant atrial dome defect was reconstructed with a bovine pericardial patch. Pathologic investigation revealed that the tumour was a bronchogenic benign cyst.

Structural conversion of three copper(ii) complexes with snapshot observations based on the different crystal colours and morphology.

Three novel Cu(ii) complexes [Cu2(L)2(MeOH)2] (1), [Cu2(L)2(H2O)2] (2) and [CuL(H2O)] (3) (L = (E)-2-((2-hydroxy-4-methoxybenzylidene)amino)acetic acid) have been obtained in different time scales of reaction processing. Complexes 1 and 2 are kinetically controlled products and 3 is a thermodynamically stable product. Single crystal X-ray diffraction analyses revealed that 1 and 2 are binuclear complexes except for different coordination solvents. 3 is a mononuclear complex. Complex 1 is mainly obtained in methanol solution, while 2 and 3 are stable in aqueous solvents. Based on the understanding of crystal structures of the three complexes, reversibly transforming crystal 2 to crystal 1 at room temperature has been realised, which has been confirmed by the change of colours and morphology measured by SEM. The research work is very important for controllable synthesis of coordination complexes.