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Zhang and Cui et al. present in situ cryoEM structures of the trimeric spike of cytoplasmic polyhedrosis virus in both open and close conformations, and demonstrate that spike detachment from the capsid is triggered by the presence of SAM and ATP.

The purpose of this paper is to establish a transition strategy for tilt-rotor vertical takeoff and landing (VTOL) unmanned aerial vehicles (UAVs) based on an optimal design method. Firstly, The flyable transition corridor was calculated based on both the UAV’s dynamic equations and its aerodynamic and dynamic characteristics. The dynamic equations of the UAV were organized into state equation forms. The initial and final value constraints of the control and state variables in the transition process were recorded, as were the constraints of the transition process. The transition strategy design problem was transformed into an optimal control problem with constraints, while the Gauss pseudospectral method (GPM) was employed to transform and solve the problem. In addition, performance indicators were designed based on the transition quality requirements for transition time, attitude stability, and control continuity. Sensitivity was analyzed according to different index terms with different dimensions and effects. Finally, the rationality of the transition strategy designed in this paper was verified according to different simulation scenarios.

Objecive: To describe the clinical and genetic findings of an Axenfeld-Rieger syndrome (ARS) family with a new PITX2 splicing mutation. Methods: A Chinese ARS family with five affected individuals was recruited. Exome sequencing was performed on the proband and the variant (C.253-9C > A) in PITX2 gene was detected as a pathogenic mutation. Sanger sequencing was performed for verification and cosegregation analysis. Real-time polymerase chain reaction (RT- PCR) and Western blotting were performed to verify the expression of the pathogenic gene. Results: All the patients showed abnormalities in the anterior segment of both eyes including posterior embryotoxon, corectopia, iris dysplasia, and iridocorneal tissue adhesions. In addition, they all presented systemic features, including maxillary hypoplasia, underbite, hypodontia, conical teeth. Only III-7 showed obvious umbilical skin. In the PITX2 family, we identified a novel heterozygous splicing mutation (C.253-9C > A) which was confirmed by Sanger sequencing to be completely cosegregated with the ARS phenotype. Real-time quantitative PCR and Western results showed that PITX2 mRNA and protein expression were significantly lower in patients compared with unrelated normal controls. Conclusion: In the ARS pedigree, we summarized the variable phenotype, described a novel PITX2 splicing mutation which expand the genetic spectrum of ARS. We further confirmed the possibility of development of ARS induced by this PITX2 gene deficiency.

This paper proposes an adaptive fault-tolerant control strategy for a hybrid vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV) to simultaneously compensate actuator faults and model uncertainties. With the proposed adaptive control schemes, both actuator faults and model uncertainties can be accommodated without the knowledge of fault information and uncertainty bounds. The proposed control scheme is constructed with two separate control modules. The low-level control allocation module is used to distribute the virtual control signals among the available redundant actuators. The high-level control module is constructed with an adaptive sliding mode controller, which is employed to maintain the overall system tracking performance in both faulty and uncertain conditions. In the case of actuator faults and model uncertainties, the adaptive scheme will be triggered to generate more virtual control signals to compensate the virtual control error and maintain the desired system tracking performance. The effectiveness of the proposed control strategy is validated through comparative simulation tests under different faulty and uncertain scenarios.

Abstract Background Currently, numerous animal studies have shown that exposure to commonly used general anesthetics during pregnancy may cause neurocognitive impairment in the offspring. Reportedly, exposure to sevoflurane during mid-trimester of pregnancy can inhibit proliferation of neural stem cells (NSCs) and lead to early apoptosis. Whether exposure to sevoflurane during pregnancy affects the differentiation of NSCs remains unclear. Methods In the present study, pregnant rats were exposed to 3% sevoflurane once for 2 h on gestational day 14 (G14) or 3 times for 2 h on G13, G14, and G15. Next, the differentiation of NSCs was measured using neuron marker β-tubulin III and astrocyte marker glial fibrillary acidic protein (GFAP) in fetal brain tissues 24 h and 72 h after anesthesia and in hippocampus on postnatal day 28. Primary cultured rat NSCs were exposed to 4.1% sevoflurane to explore the mechanism. Results The results showed that during mid-trimester, multiple exposures to sevoflurane can cause premature differentiation of NSCs in developing brains of offspring and lead to long-term neuron reduction and astrocyte proliferation in hippocampus. The data from the present study indicated that repeated exposure to sevoflurane downregulated atrophin-1 (ATN1) expression and caused early differentiation of NSCs. Overexpression of ATN1 via lentivirus transfection attenuated the influence of sevoflurane. Using dual luciferase assay, ATN1 was found to be a target gene of microRNA-410-3p (miR-410-3p). MiR-410-3p suppression via lentivirus transfection recovered the ATN1 expression and differentiation of NSCs. Conclusions The results from the present study demonstrated that repeated exposure to sevoflurane leads to early differentiation of NSCs and long-term effects via the miR-410-3p/ATN1 pathway.

With the construction of intelligent transportation systems in recent years, intelligent methods for the prediction of traffic flow are becoming more and more important, and accurate prediction plays a key role in enabling downstream scheduling algorithms. However, the accuracy of most current forecasting algorithms remains unsatisfactory. Because traffic depends on the time of the day and varies throughout the week, such as during peak commuting periods as opposed to other times, traffic flow data show evident cyclical patterns. We capitalize on this notion and propose a multiscale convolutional feedback network for frequency prediction based on frequency angle. We combine multiscale convolution (MSC) with dilated convolution, and increase the convolutional receptive field by expanding cavity size while retaining similar parameterization costs, and achieve multiscale convolution with kernels referring to different receptive fields. At the same time, we incorporate an autoencoding module by assigning the same set of hidden features to input reconstruction and output prediction, which results in enhanced stability of features within the hidden layers. When we tested our approach on the Traffic dataset, our model achieved the best performance as assessed via the three indicators measured using mean squared error (MSE), mean absolute error (MAE), and correlation coefficient (CORR), with improvements of 3.818%, 2.472% and, 0.1515%, respectively.

Since the application of silicon materials in electronic devices in the 1950s, microprocessors are continuously getting smaller, faster, smarter, and larger in data storage capacity. One important factor that makes progress possible is decreasing the dielectric constant of the insulating layer within the integrated circuit (IC). Nevertheless, the evolution of interlayer dielectrics (ILDs) is not driven by a single factor. At first, the objective was to reduce the dielectric constant (k). Reduction of the dielectric constant of a material can be accomplished by selecting chemical bonds with low polarizability and introducing porosity. Moving from silicon dioxide, silsesquioxane-based materials, and silica-based materials to porous silica materials, the industry has been able to reduce the ILDs’ dielectric constant from 4.5 to as low as 1.5. However, porous ILDs are mechanically weak, thermally unstable, and poorly compatible with other materials, which gives them the tendency to absorb chemicals, moisture, etc. All these features create many challenges for the integration of IC during the dual-damascene process, with plasma-induced damage (PID) being the most devastating one. Since the discovery of porous materials, the industry has shifted its focus from decreasing ILDs’ dielectric constant to overcoming these integration challenges. More supplementary precursors (such as Si–C–Si structured compounds), deposition processes (such as NH3 plasma treatment), and post porosity plasma protection treatment (P4) were invented to solve integration-related challenges. Herein, we present the evolution of interlayer dielectric materials driven by the following three aspects, classification of dielectric materials, deposition methods, and key issues encountered and solved during the integration phase. We aim to provide a brief overview of the development of low-k dielectric materials over the past few decades.

Purpose: This paper examines the underpinning factors responsible for child streetism in Dar es Salaam and Dodoma cities, Tanzania. Methodology: The study employed a qualitative method. Instruments for data collection included participants' interviews, key informant interviews, and document review. The adopted research paradigm was the interpretivism research paradigm. This paradigm was chosen on the basis that the study wanted to have in-depth information on the influence of income poverty and family development on child streetism adopting the qualitative nature of the research. The adopted research approach was the inductive research approach because of the qualitative nature of the study. The population consisted of street children living on the streets of Dodoma and Dar es Salaam cities in Tanzania while the study sample size included 38 street children and 18 key informants. Findings: The findings revealed that income, poverty, and Lack of family capacity to meet children's basic needs such as food, shelter, clothes, education, and health needs were the main causes of child streetism. The study findings are also supported by the vulnerability theory. The theory shows how vulnerable environments including poverty may lead to certain social consequences. According to this theory, children's vulnerability is explained in different ways including being victims of hunger and homelessness, which is considered an identity of a vulnerable population. Unique Contribution to Theory, Practice and Policy: Vulnerability theory recognizes that the human experience of constant vulnerability varies as a result of stages in the life course, social institutions, and law, which often trace intersecting forms of oppression on the basis of race, gender, sexuality, disability, and class. Vulnerability thus provides a heuristic device for exposing the structural privilege and disadvantage enveloped in these relationships and suggests ways to readjust them in order to advance social justice and lessen inequality. It is recommended that the Regional Administrations and Local Government Authorities in collaboration with other stakeholders establish a special campaign to enroll street children into the education system and facilitate family reunification. [ABSTRACT FROM AUTHOR]

This paper discusses the control strategy for energy management in railway transit network with wayside (substation) supercapacitor (SC) energy storage system (ESS). Firstly, the structure of the wayside energy storage system is introduced. Secondly, the model of energy storage system is built and the control strategy is described. Thirdly, in order to estimate the required energy storage system, a useful method is proposed to predict the instantaneous regenerative energy magnitude which is delivered to each substation. Finally, the ESS configuration for each substation is determined. A simplified mathematical model of the whole metro network is established and the main features of the control strategy are developed. Numerical simulations show the efficacy of suggested control strategy and the energy saving obtained for railway transit network.

Transfer entropy (TE) is a model-free approach based on information theory to capture causality between variables, which has been used for the modeling and monitoring of, and fault diagnosis in, complex industrial processes. It is able to detect the causality between variables without assuming any underlying model, but it is computationally burdensome. To overcome this limitation, a hybrid method of TE and the modified conditional mutual information (CMI) approach is proposed by using generated multi-valued alarm series. In order to obtain a process topology, TE can generate a causal map of all sub-processes and modified CMI can be used to distinguish the direct connectivity from the above-mentioned causal map by using multi-valued alarm series. The effectiveness and accuracy rate of the proposed method are validated by simulated and real industrial cases (the Tennessee-Eastman process) to capture process topology by using multi-valued alarm series.

In this study, methasterone urinary metabolic profiles were investigated by liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS) in full scan and targeted MS/MS modes with accurate mass measurement. A healthy male volunteer was asked to take the drug and liquid–liquid extraction was employed to process urine samples. Chromatographic peaks for potential metabolites were hunted out with the theoretical [M − H]− as a target ion in a full scan experiment and actual deprotonated ions were studied in targeted MS/MS experiment. Fifteen metabolites including two new sulfates (S1 and S2), three glucuronide conjugates (G2, G6 and G7), and three free metabolites (M2, M4 and M6) were detected for methasterone. Three metabolites involving G4, G5 and M5 were obtained for the first time in human urine samples. Owing to the absence of helpful fragments to elucidate the steroid ring structure of methasterone phase II metabolites, gas chromatography mass spectrometry (GC-MS) was employed to obtain structural information of the trimethylsilylated phase I metabolite released after enzymatic hydrolysis and the potential structure was inferred using a combined MS method. Metabolite detection times were also analyzed and G2 (18-nor-17β-hydroxymethyl-2α, 17α-dimethyl-androst-13-en-3α-ol-ξ-O-glucuronide) was thought to be new potential biomarker for methasterone misuse which can be detected up to 10 days.

It is important to study the properties and mechanics of egg drop impacts in order to reduce egg loss during processing and logistics and to provide a basis for the protective packaging of egg products. In this paper, we present the results of our study of the effects of the structural parameters on the mechanical properties of an egg using a finite element model of the egg. Based on Fluid-Solid coupling theory, a finite element model of an egg was constructed using ADINA, a finite element calculation and analysis software package. To simplify the model, the internal fluid of the egg was considered to be a homogeneous substance. The egg drop impact was simulated by the coupling solution, and the feasibility of the model was verified by comparison with the experimental results of a drop test. In summary, the modeling scheme was shown to be feasible and the simulation results provide a theoretical basis for the optimum design of egg packaging and egg processing equipment. [ABSTRACT FROM AUTHOR]

The analytical data for identifying an unknown substance that was found in a nutrition supplement is presented. The unknown substance is purified using thin-layer chromatography and then measured using high-resolution mass spectrometry (HRMS) giving the exact mass from which the structure of the unknown substance was proposed. The procedure for synthesizing N-nitrosofenfluramine from fenfluramine is described. The extracted, synthesized, and standard N-nitrosofenfluramine are compared using HRMS, high-performance liquid chromatography (HPLC)–MS, HPLC–UV, Fourier transform IR spectroscopy, gas chromatography–MS, TLC, and NMR (1H NMR and 13C NMR). All analytical data obtained confirm that the unknown peak in the nutrition supplement is N-nitrosofenfluramine and that the synthetic procedure described can easily provide the N-nitrosofenfluramine reference substance for identification. [ABSTRACT FROM AUTHOR]

Recent studies show that heterochromatin-associated protein-1 (HP1) recognizes a `histone code' involving methylated Lys9 (methyl-K9) in histone H3. Using in situ immunofluorescence, we demonstrate that methyl-K9 H3 and HP1 co-localize to the heterochromatic regions of Drosophila polytene chromosomes. NMR spectra show that methyl-K9 binding of HP1 occurs via its chromo (&chrbline;omosome &obline;rganization &mobline;difier) domain. This interaction requires methyl-K9 to reside within the proper context of H3 sequence. NMR studies indicate that the methylated H3 tail binds in a groove of HP1 consisting of conserved residues. Using fluorescence anisotropy and isothermal titration calorimetry, we determined that this interaction occurs with a KD of ∼-100 μM, with the binding enthalpically driven. A V26M mutation in HP1, which disrupts its gene silencing function, severely destabilizes the H3-binding interface, and abolishes methyl-K9 H3 tail binding. Finally, we note that sequence diversity in chromo domains may lead to diverse functions in eukaryotic gene regulation. For example, the chromo domain of the yeast histone acetyltransferase Esa1 does not interact with methyl- K9 H3, but instead shows preference for unmodified H3 tail. [ABSTRACT FROM AUTHOR]

Reports on the development of an approach to identify backbone conformational changes underlying nicotinic acetylcholine receptor gating. Gating and function of receptors with ester backbones; Facilitation of gating by an ester at residue 221; Sensitivity of some M2 domain backbone esters; Single-channel currents and voltage dependence for receptors.

Examines whether the ODR-10 protein is an odorant receptor. Necessity of expressing the protein in a heterologous system; Type of elevation exhibited by human cells expressing ODR-10 on their surfaces; Identification of the compounds which ODR-10 expressed in human cells respond to; What the results of the study illustrate.