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tert-Butoxide unlocks new reactivity patterns embedded in nitroarenes. Exposure of nitrostilbenes to sodium tert-butoxide was found to produce N-hydroxyindoles at room temperature without an additive. Changing the counterion to potassium changed the reaction outcome to yield solely oxindoles through an unprecedented dioxygen-transfer reaction followed by a 1,2-phenyl migration. Mechanistic experiments established that these reactions proceed via radical intermediates and suggest that counterion coordination controls whether an oxindole or N-hydroxyindole product is formed.

A laser Doppler velocimeter (LDV) is usually integrated with an inertial navigation system (INS) to autonomously acquire a vehicle’s position, velocity and attitude. The calibration process is trying to determine the scale factor of the LDV and the installation angles between LDV and INS. As a dead-reckoning system, the calibration accuracy affects the navigation performance of the LDV/INS integrated navigation system. This paper presents how to use time-differenced carrier phase (TDCP) observations instead of differenced GPS (DGPS) or precise point positioning (PPP) techniques to complete the calibration process. Differencing carrier phase observations between two GPS epochs can save the effort in ambiguity fixing and achieve centimeter relative positioning after outlier and cycle slip detection, which is suitable for LDV calibration. In order to finish the calibration within several minutes, an iteration scheme is implemented into the calibration for rapid convergence. The navigation experiment indicates that the horizontal position error of the LDV/INS integrated navigation system can achieve 26.6m/25.5km.

In recent years, the development of new energy vehicles in the world has entered the industrial scale, but electric vehicles (EVs) have the disadvantage of short driving range due to the capacity of the battery, which need to supplement electric energy in charging stations. Although the number of charging piles for EVs is increasing day by day, its growth rate has not caught up with the charging demand for EVs. In order to provide personalized charging service for users with convenient power consumption and efficient charging, a set of intelligent recommendation model for EV charging is proposed based on collaborative filtering algorithm, which provides optimal charging method based on the user's historical behavior data.

In this paper, we focus on how gravity anomaly affects height estimation in the high-precision inertial navigation system (INS) and global navigation satellite system (GNSS) integration. The theoretical analysis based on INS error propagation equations shows that the height error is related to gravity anomaly directly. In addition, the height-related elements in the Kalman gain matrix can be used as an indicator to evaluate the extent of the effect to height estimation. Different precision grade INSs integrated with GNSS, and GNSS of different positioning accuracy integrated with high-precision INS is simulated to analyze the effect of gravity anomaly. The simulation results show that the effect can be ignored in low-precision INS cases, while is more significant in high-precision cases, which agrees well with the former theoretical analysis. At last, a shipborne test is conducted and the experimental results show that the maximum height error of high-precision INS/GNSS integration can reach to 0.5 m if the gravity anomaly is not compensated, while can fall below than 0.1 m after gravity anomaly compensation or modeling. It shows that the existence of gravity anomaly along the track can degrade the vertical positioning accuracy of high-precision INS/GNSS integration, and should be considered in such cases.

As little as 2 mol % of (XPhos)AuNTf2 catalyzes the transformation of a broad range of o-acetylene-substituted styrenes into 1,2-dihydronaphthalenes. Our data suggests that this transformation occurs via a gold-stabilized cyclopropyl carbinyl cation, which triggers either a [1,2] carboxylate shift or a less favorable [1,2] aryl shift. The relative rates of these migrations can be controlled by the identity of the ligand or by stabilizing the mesomeric cation.

Long non-coding RNA (lncRNA) plays an important regulatory role in plant growth and development, but its systematic identification and analysis in Eucalyptus has not yet been reported. Cold stress has a huge impact on the survival and yield of Eucalyptus seedlings, but the regulatory mechanism of lncRNA in Eucalyptus in response to cold stress is still unclear. In this study, the transcriptomes of young leaves of Eucalyptus urophylla S.T.Blake under low-temperature treatment and restoration were analyzed by RNA-seq. A total of 11,394 lncRNAs and 46,276 mRNAs were identified, of which 300 were differentially expressed lncRNAs (DE_lncRNAs) and 5606 were differentially expressed target genes of lncRNAs under cold stress, with the total number of target genes of DE_lncRNAs being 1681. A total of 677 differentially expressed transcription factors (TFs) were also identified, mainly including ERF, MYB and the NAC transcription factor family. Gene ontology (GO) analysis of the differentially expressed genes (DEGs) and target genes of DE_lncRNAs was mostly related to the response to cold stress and external stimuli. Furthermore, lncRNA–miRNA–mRNA regulatory networks were constructed, and 22 DE_lncRNAs were predicted to be targets or targeting mimics of 20 miRNAs. A qRT-PCR was used to verify the relative expression of genes in the regulatory EuGBF3-EUC_00002677-MSTRG.7690 network, and it matched the transcriptome data, indicating that it may play an important role in the response to cold stress in E. urophylla. This study provides a new insight into lncRNA and its regulatory network under abiotic stress, especially cold stress in E. urophylla.

We describe a multicenter study using the European Spine Phantom (ESP) to compare the accuracy, linearity and precision of QCT measurements of spine vBMD between different brands of scanner, different models of the same brand and identical units of the same model. Ten scans of the same ESP with repositioning were performed on forty CT scanners from five manufacturers in different hospitals across China, all calibrated with the Mindways QCT system. The three ESP vertebral bodies simulating low (L1), medium (L2) and high (L3) vBMD and their average (L1-3 vBMD) were compared with phantom values. Linearity was assessed using the standard error of the estimate derived from linear regression. Precision errors were expressed as the standard deviation of the ten measurements on each scanner. Median (IQR) vBMD over all forty CT scanners compared with phantom values were: L1: 52.2 (49.9-56.4) vs 51.0; L2: 104.4 (101.2-108.6) vs 102.2; L3: 201.4 (195.0-204.9) vs 200.4; L1-3: 119.3 (116.6-123.2) vs 117.9 mg/cm3. Statistically significant differences in L1-3 vBMD were found between different brands (p= 0.005) and between different models of the same brand and identical units of the same model (both p< 0.001). Cross-calibration using linear regression gave a good fit for all forty systems with a median standard error of the estimate of 1.7 mg/cm3. The median precision error for L1-3 vBMD was 0.61 mg/cm3. Statistically significant differences in spine vBMD measurements between different scanners reinforce the importance of cross-calibration in multi-center studies. Cross-calibration can be reliably performed using linear regression equations.

Ascorbate peroxidase (APX) is an important antioxidant enzyme. APXs in maize are encoded by multiple genes and exist as isoenzymes. The evolutionary history and functional divergence of the maize APX gene family were analyzed through comparative genomic and experimental data on the Internet in this paper. APX genes in higher plants were divided into classes A, B, and C. Each type of APX gene in angiosperms only had one ancestral gene that was duplicated along with the genome duplication or local (or tandem) duplication of the angiosperm. A total of eight genes were retained in maize and named APXa1, APXa2, APXa3, APXb1, APXb2, APXc1.1, APXc1.2, and APXc2. The APX genes of class A were located in the chloroplasts or mitochondria, and the class B and C genes were localized in the peroxisomes and cytoplasm, respectively. The expression patterns of eight APXs were different in vegetative and reproductive organs at different growth and development stages. APXa1 and APXb1 of maize may participate in the antioxidant metabolism of vegetative organs under normal conditions. APXa2, APXb2, APXc1.1, and APXc1.2 may be involved in the stress response, and APXb2 and APXc2 may participate in the senescence response. These results provide a basis for cultivating high-yield and resistant maize varieties.

We herein establish a multicomponent annulation method for the synthesis of valuable iminocoumarins using aryl thiocarbamates, internal alkynes, and sulfonamides as starting materials, which are safe and readily available. The key step is a Rh-catalyzed and sulfur-directed C-H bond activation. Preliminary mechanistic investigations suggested that the nucleophilic attack of the sulfonamide on an active iminium cation finally completes the imine segment.

Cross-coupling reactions involving metal carbene intermediates play an increasingly important role in C–C bond formation. Expanding the carbene precursors to a broader range of starting materials and more diverse products is an ongoing challenge in synthetic organic chemistry. Herein, we report a Suzuki-Miyaura coupling reaction of in situ-generated Pd–carbene complexes via desulfurization of thioureas or thioamides. This strategy enables the preparation of a broad array of substituted amidinium salts and unsymmetrical diaryl ketones. The reaction is readily scalable, compatible with bromo groups on aromatic rings, tolerant to moisture and air and has a broad substrate scope. Furthermore, a single crystal structure of Pd-diaminocarbene complex is obtained and proven to be the key intermediate in both catalytic and stoichiometric reactions. Preliminary mechanistic studies demonstrate the dual role of the silver salt as a desulfurating reagent assisting the elimination of sulfur and as oxidant facilitating the PdII/Pd0/PdII catalytic cycle., Alternative carbene precursors for metal-catalyzed cross coupling may expand the portfolio of methods for C-C bond construction. Here, the authors report a Suzuki−Miyaura coupling of Pd−carbene complexes formed by desulfurization of thioureas or thioamides and affording a broad array of amidinium salts and diaryl ketones.

Recent studies have demonstrated that nicotine exhibited anti-inflammatory and neuroprotective properties by interacting with the alpha 7 nicotinic acetylcholine receptor (α7nAChR). However, the role of nicotine in regeneration during peripheral nerve injury has not been elucidated. The aim of this study was to investigate whether nicotine down-regulated production of proinflammatory cytokines and promoted peripheral nerve regeneration in rats. Rats challenged with sciatic nerve crush injury were treated with nicotine (1.5 mg/kg), three times per day. The expression of the proinflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin (IL-1β), pinch test results, growth-associated protein 43 (GAP-43) expression, morphometric analyses, and the sciatic functional indexes were determined in sciatic nerves. Treatment with nicotine decreased local levels of TNF-α and IL-1β, and increased the expression of GAP-43. Nicotine also improved nerve regeneration and functional recovery. The overall protective effects of nicotine were reversed by concomitant treatment with α7nACHR antagonist methyllycaconitine, indicating that nicotine exerted its specific anti-inflammatory and neuroprotective effects through the α7nAChR. These findings show that nicotine administration can provide a potential therapeutic pathway for the treatment of peripheral nerve injury, by a direct protective effect through the α7nAChR-mediated cholinergic anti-inflammatory pathway.

In this paper, we integrate the high-precision inertial navigation system (INS) with the GPS precise point positioning (PPP) by using the tightly-coupled architecture, which aims to obtain the preferable attitude and positioning information in the remote marine applications. The structure of INS/PPP tightly-coupled integrated navigation is presented firstly in the paper. Then, the observation model in the local geographic frame (ENU frame) is derived, where the Extend Kalman filter (EKF) is used for the information fusion. Finally, a real shipborne marine test is conducted to test the performance of INS/PPP tightly coupled integration. The experimental results show that the positioning accuracy of the integrated navigation system can be better than 10cm in the horizontal axis and 20cm for the vertical channel, and the attitude estimation error can be smaller than 1 arcsec. Besides this, the performance the tightly-coupled integration can be maintained during 100s simulated signal outages, while that performance of loosely-coupled integration will degrade significantly in such a case.

This paper investigates the attitude estimation errors caused by the deflections of vertical (DOV) in the case of a rotational inertial navigation system (INS) integrated with a global satellite navigation system (GNSS). It has been proved theoretically and experimentally that the DOV can introduce a tilt error to the INS/GNSS integration, whereas less attention has been given to its effect to the heading estimation. In fact, due to the intercoupling characteristic of attitude errors, the heading estimation of an INS/GNSS integrated navigation system can also be affected. In this paper, first, the attitude estimation errors caused by DOV were deduced based on the INS&rsquo, s error propagation functions. Then, the corresponding simulations were conducted and the results were well consistent with the theoretical analysis. Finally, a real shipborne marine test was organized with the aimed to verify the effect of DOV on attitude estimation in the rotational INS/GNSS integration, whereas the global gravity model was used for DOV compensation. The results with DOV compensation were compared with the corresponding results where the compensation was not used and showed that the heading estimation errors caused by DOV could exceed 20 arcsecs, which must be considered in high-precision application cases.

An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis(pinacolato)diboron was developed, affording β-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.

C-N bond formation via a copper-catalyzed aerobic oxidative decarboxylative tandem protocol was realized. The phenylacetic acids which contain ortho-X (X = F or Br) on the aromatic ring will render a fused five-membered heterocycle via a tandem aromatic nucleophilic substitution and aerobic oxidative decarboxylative acylation at the C(sp(2))-H bond of benzimidazoles under the Cu(OAc)2/K2CO3/BF3·Et2O catalytic system, while with CuBr as the catalyst and pyridine as the base, N-acylation occurred and tertiary amides were obtained.

Catalyzed by a simple copper salt, the reaction of an aryl aldehyde and a terminal alkyne in the presence of piperidine delivers the valuable chalcone products, which were rarely found in previous A3 coupling reactions. This reaction can be applied to a wide range of substrates. Mechanistic studies indicate that this reaction experiences a tandem process containing A3 coupling, copper assisted isomerization of propadienamine to allenylamine and subsequent hydrolysis.

OBJECTIVES: This current study is aimed to investigate effects of protein diet on immune and inflammation responses in colon using an intestinal-epithelial-cells (IECs)-specific Heterogeneous Nuclear Ribonucleoprotein (hnRNPI) Knockout mouse model. We hypothesized that protein diet may be beneficial for the KO mice by maintaining their colon immune functions and reducing inflammation. METHODS: In this experiment, the wild-type (WT) group includes the hnRNPIflox/+ mice and the hnRNPIflox/flox mice, heterozygotes are the hnRNPIflox/+; VillinCre/+ mice, and the knockout (KO) mice are the hnRNPIflox/flox; VillinCre/+ mice, intestinal epithelial cells only. Both WT and KO mice in CON group were provided a control diet containing 12.57% kcal from protein, while the treatment group was provided with a protein diet containing 25.15% kcal from protein. Quantitative RT-PCR was performed to examine gene expressions, immunohistochemistry staining was performed to examine CD4 + cells and enzyme-linked immunosorbent assay was performed to examine TNF-α concentration in blood circulation. RESULTS: 1With protein diet, mRNA expression of pro-inflammatory cytokines and chemokines–IL-6, IL-1β, Cxcl1, and Ccl2–were significantly lowered in both male and female KO mice, comparing to CON. Expression of IL-10, an immunomodulatory cytokine, showed no significant difference among KO mice in male, however, was significantly increased by protein diet in female KO comparing to CON. Protein diet has no effect on expressions of PD1, PDL1, and PDL2 in male KO mice, but significantly decreased expression of PD1 and PDL1 in female KO mice comparing to CON. ELISA results suggest that both male and female KO mice fed with protein diet had significantly lowered the level of TNF-α comparing to those fed with CON diet in blood circulation. Both male and female KO mice fed with protein diet had significantly lowered CD4 positive cells stained comparing to CON. CONCLUSIONS: In summary, this current study reports that protein diet provides beneficial effects to IECs-specific-hnRNPI knockout mice by downregulating expressions of pro-inflammatory markers in colon. It also regulates PD1 and PDL1 expression, however only in female. FUNDING SOURCES: This project was supported by the USDA Cooperative State Research, Education and Extension Service, Hatch project numbers # ILLU-971-351 and ILLU-698-369.

Docosahexaenoic acid (DHA) is an omega-3 fatty acid that is highly abundant in the brain and confers protection against numerous neurological diseases, yet the fundamental mechanisms regulating the enrichment of DHA in the brain remain unknown. Here, we have discovered that a member of the long-chain acyl-CoA synthetase family, Acsl6, is required for the enrichment of DHA in the brain by generating an Acsl6-deficient mouse (Acsl6(−/−)). Acsl6 is highly enriched in the brain and lipid profiling of Acsl6(−/−) tissues reveals consistent reductions in DHA-containing lipids in tissues highly abundant with Acsl6. Acsl6(−/−) mice demonstrate motor impairments, altered glutamate metabolism, and increased astrogliosis and microglia activation. In response to a neuroinflammatory lipopolysaccharide injection, Acsl6(−/−) brains show similar increases in molecular and pathological indices of astrogliosis compared with controls. These data demonstrate that Acsl6 is a key mediator of neuroprotective DHA enrichment in the brain.

In high-precision GNSS/INS integrated navigation systems, the effect of gravity disturbance to the position, velocity and attitude estimation should be considered. The velocity and position errors induced by gravity disturbance can be corrected directly by GNSS position and velocity through Kalman filtering. The horizontal components of gravity disturbance defined as DOV can affect the roll and pitch estimation and should be compensated by gravity map products, such as EGM2008 or other earth gravity models. While the effect of gravity anomaly to the attitude estimation is usually ignored, since it is much smaller than normal gravity and can be absorbed by the vertical accelerometer’s bias. However, in some special cases, such as IMU rotating around one certain horizontal axis, the gravity anomaly can transfer to horizontal accelerometers, and introduce attitude estimation error. In this paper, we analyze the effect of gravity anomaly on attitude estimation in GNSS/INS integrated navigation systems under overturning cases. A theoretical analysis in the case that IMU rotate around east-axis and north-axis to the attitude estimation is derived based on IMU error propagation functions. It is indicated that the rotation around east-axis (north-axis) can introduce pitch (roll) estimation error proportional to gravity anomaly, the yaw estimation is also be affected due to the intercoupling characteristic of attitude errors, and which more sensitive to the rotation around east-axis while not north-axis. Then, the simulation is conducted and agrees well with the theoretical results. Finally, an RLG (Ring Laser Gyroscope) IMU, which has similar quality to Honeywell HG9900, is fixed on a dual-axis turntable to access the effect of gravity anomaly. The experimental result shows that the yaw error induced by gravity anomaly with magnitude 100mGal can reach 15 arcsecs when IMU rotation around a certain horizontal axis at an angle rate of 1.5°/s°.

A palladium-catalyzed dual ortho C–H bond activation of aryl thiocarbamates is developed. This tandem reaction initiates by thiocarbamate-directed ortho C–H palladation, which leads to favorable olefin insertion rather than reductive elimination. The oxidative Heck reaction followed by another C–H activation and sulfuration affords the dual-functionalized products. This reaction provides a concise route to the S,O,C multisubstituted benzene skeleton which could be successfully applied for the synthesis of a COX-2 inhibitor.

Implementing the global positioning system (GPS) total carrier phase observations based on the precise point positioning (PPP) technique in a navigation Kalman filter can improve the position accuracy of a GPS/inertial measurement unit (IMU) tightly coupled navigation system to the sub-meter level. However, the carrier phase implementation introduces extra states such as ambiguities, to the Kalman filter state vector, which increases the computational burden especially when nonlinear filtering methods are applied. In this paper, in order to reduce the computational burden of the PPP/IMU tightly coupled navigation system, a cubature Kalman filter (CKF) + extended Kalman filter (EKF) hybrid filtering method by applying a linear filtering method to estimate the linear states mainly GPS related states, while a nonlinear filtering method to estimate the nonlinear states such as IMU related states, is proposed. The hybrid filtering method can make a balance between keeping the CKF benefits in dealing with nonlinear problems and reducing the computational time. The simulation and experiment results show the effectiveness of the method.

The “Unity of Knowing and Doing” (UKD) theory is proposed by an ancient Chinese philosopher, Wang Shouren, in 1508, which explains how to unify knowledge and practice. Different from the Chinese traditional UKD theory, the international higher education usually treats knowledge and practice as independent, and puts more emphasis on knowledge. Oriented from the UKD theory, the College of Opto-electric Science and Engineering (COESE) at National University of Defense Technology (NUDT) explores a novel training model in cultivating opto-electric professionals from the aspects of classroom teaching, practice experiment, system experiment, design experiment, research experiment and innovation experiment (CPSDRI). This model aims at promoting the unity of knowledge and practice, takes how to improve the students’ capability as the main concern and tries to enhance the progress from cognition to professional action competence. It contains two hierarchies: cognition (CPS) and action competence (DRI). In the cognition hierarchy, students will focus on learning and mastering the professional knowledge of optics, opto-electric technology, laser, computer, electronics and machine through classroom teaching, practice experiment and system experiment (CPS). Great attention will be paid to case teaching, which links knowledge with practice. In the action competence hierarchy, emphasis will be placed on promoting students’ capability of using knowledge to solve practical problems through design experiment, research experiment and innovation experiment (DRI). In this model, knowledge is divided into different modules and capability is cultivated on different levels. It combines classroom teaching and experimental teaching in a synergetic way and unifies cognition and practice, which is a valuable reference to the opto-electric undergraduate professionals’ cultivation.

A palladium-catalyzed intramolecular C-H bond sulfuration reaction of aryl thiocarbamates has been developed. This strategy provides a new route to benzo[d][1,3] oxathiol-2-ones with tolerance of a wide range of substituents. Mechanistic studies suggested that the C-H activation-sulfuration to afford 2-imino-1,3-benzoxathiole intermediate might involve an electrophilic palladation process.

A direct synthesis of polysubstituted olefins via construction of C-C bonds, which involves the direct dehydrative coupling of alcohols or alkenes with alcohols, was realized using a series of alkanesulfonic acid group-functionalized ionic liquids (SO 3 H-functionlization ILs) without additives. The metal-free and recyclable catalyst system avoided the disposal and neutralization of acidic catalysts after reaction and tolerated a broad range of substrates, including benzylic, allyl, propargylic, aliphatic and aromatic or aliphatic olefins. Additionally, the catalytic system was suitable for a gram-scale preparation. Preliminary mechanistic studies indicated that the C-H bond cleavage in this reaction might be involved in the rate-determining step.

The laser Doppler velocimeter (LDV) is integrated with inertial navigation systems (INS) to form an integrated navigation system to acquire the land vehicle’s orientation, velocity, and position. As an integrated navigation system, the calibration items, including scale factor error of the LDV and the installation angle error between the INS and the LDV, should be well calibrated; otherwise the accuracy of navigation performance will be seriously affected. The paper represents a method about applying time-differenced carrier phase observations to deliver accurate reference velocity for calibration instead of differenced GPS (DGPS) or precise point position (PPP). The differential carrier phase between successive GPS epochs eliminates the effort of ambiguity and it is able to achieve millimetre-level relative velocity accuracy within minutes. In order to make up for the insufficient of calibration time, a iteration method is implemented for fast convergence. The navigation experiment shows that the calibrated LDV/INS navigation system can reach 34.7m/25.5km in horizon and 4.8m/25.5km in vertical.

The palladium-catalyzed Sonogashira-type aerobic oxidative coupling of arylhydrazines with terminal alkynes via C-N bond cleavage has been developed; internal alkynes were afforded with a broad substrate scope. This reaction proceeds under copper- and base-free conditions with molecular oxygen as the sole oxidant and nitrogen and water as the only by-products.

An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis(pinacolato)diboron was developed, affording β-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.