Substrate-directed regioselective alkene functionalizations of (E)-ß,γ-unsaturated carboxylic acids.

A carboxylate-directed regioselective Heck-type alkenylation and alkenylative lactonization of (E)-ß,γ-unsaturated carboxylic acids by simply substrate control is reported. (E)- and (Z)-alkenyl bromides reacted to give energetically more favorable palladacyles, allowing access to fully stereocontrolled conjugated 1,3-dienes and alkenyled γ-lactones. Mechanistic studies suggest that excellent regioselectivity may be strongly influenced by the steric factors of reactants involved in the palladacycle intermediates.

Decomposing high uncertainty in greenhouse gas mitigation pathways in emerging regions: An approach to evaluate risks toward carbon neutrality.

In the context of ambitious greenhouse gas (GHG) mitigation strategies in emerging regions, addressing the prevailing uncertainty and its key influential factors is crucial. While uncertainty analysis of GHG mitigation pathways has been extensively explored, the systematic identification and quantification of pivotal factors has been notably absent. This study introduces a novel methodology that combines Quasi-Monte Carlo simulation with Sobol variance decomposition, which identifies key influential factors and traces the flow of uncertainties. Applied in Anhui Province, a rapidly developing region in China, our findings indicate an uncertain GHG emission proportion of 6.2 % by 2030, escalating to 68.6 % by 2060, with a 95 % confidence interval. This uncertainty results in a cumulative projection error of 2.1 billion tons of CO2e from 2020 to 2070. The per capita GDP factor emerges as the predominant influence, alongside the increasing impact of renewable energy factor and UHV import electricity factor. In our uncertainty flow analysis, the energy transformation sector is identified as the principal contributor to total uncertainty, driven significantly by economic and energy-related factors. These results underscore the critical need for policymakers in emerging regions to incorporate uncertainty decomposition analysis into their strategic planning to mitigate risks in GHG reduction efforts.

An improved tetracycline-inducible expression system for fission yeast.

The ability to manipulate gene expression is valuable for elucidating gene function. In the fission yeast Schizosaccharomyces pombe, the most widely used regulatable expression system is the nmt1 promoter and its two attenuated variants. However, these promoters have limitations, including a long lag, incompatibility with rich media, and unsuitability for non-dividing cells. Here, we present a tetracycline-inducible system free of these shortcomings. Our system features the enotetS promoter, which achieves a similar induced level and a higher induction ratio compared to the nmt1 promoter, without exhibiting a lag. Additionally, our system includes four weakened enotetS variants, offering an expression range similar to the nmt1 series promoters but with more intermediate levels. To enhance usability, each promoter is combined with a Tet-repressor-expressing cassette in an integration plasmid. Importantly, our system can be used in non-dividing cells, enabling the development of a synchronous meiosis induction method with high spore viability. Moreover, our system allows for the shutdown of gene expression and the generation of conditional loss-of-function mutants. This system provides a versatile and powerful tool for manipulating gene expression in fission yeast.

Encapsulation of the vanadium substituted Keggin polyoxometalates [α-PVW11O40]4- and [α-PV2W10O40]5- in HKUST-1.

Two POM@MOF hybrid materials composed of a copper-based metal-organic framework (MOF) [Cu3(C9H3O6)2(H2O)3]n (HKUST-1) encapsulating vanadium-substituted Keggin polyoxometalates (POM), [α-PVW11O40]4- (PVW11) and [α-PV2W10O40]5- (PV2W10), were prepared and characterized. PVW11@HKUST-1 and PV2W10@HKUST-1 were synthesized hydrothermally by self-assembly of HKUST-1 in the presence of the preformed POMs, [α-PVW11O40]4- and [α-PV2W10O40]5-, respectively. The two POM@MOF composites were characterized by X-ray diffraction, TGA, BET surface area analysis and FT-IR and Raman spectroscopy. The electronic structure of the POM@MOF materials and their respective constituents is surveyed using solid state UV-vis reflectance spectroscopy. The UV-vis spectra order the oxidizing strength of the POM constituents ([α-PV2W10O40]5- > [α-PVW11O40]4-) and reveal the distinct electronic structure of the POM@MOF materials obtained by synthetic encapsulation of mono- and di-vanadium substituted Keggin polyoxotungstates in HKUST-1.

Met1-linked ubiquitination in cell signaling regulation.

Met1-linked ubiquitination (Met1-Ub), also known as linear ubiquitination, is a newly identified atypical type of polyubiquitination that is assembled via the N-terminal methionine (Met1) rather than an internal lysine (Lys) residue of ubiquitin. The linear ubiquitin chain assembly complex (LUBAC) composed of HOIP, HOIL-1L and SHARPIN is the sole E3 ubiquitin ligase that specifically generates Met1-linked ubiquitin chains. The physiological role of LUBAC-mediated Met1-Ub has been first described as activating NF-κB signaling through the Met1-Ub modification of NEMO. However, accumulating evidence shows that Met1-Ub is broadly involved in other cellular pathways including MAPK, Wnt/ß-Catenin, PI3K/AKT and interferon signaling, and participates in various cellular processes including angiogenesis, protein quality control and autophagy, suggesting that Met1-Ub harbors a potent signaling capacity. Here, we review the formation and cellular functions of Met1-linked ubiquitin chains, with an emphasis on the recent advances in the cellular mechanisms by which Met1-Ub controls signaling transduction.

LC-MS based strategy for chemical profiling and quantification of dispensing granules of Ginkgo biloba seeds.

Ginkgo biloba seeds have been used as a traditional Chinese medicine for hundreds of years to treat diseases such as cervicitis, cough, asthma and other lung diseases. As a novel form, the dispensing granules (GSDG) of Ginkgo biloba seeds have been widely employed in clinic. However, its chemical profiling is not yet clear, which has restricted in-depth research in many fields. In this study, a high performance liquid chromatography coupled with quardrupole time-of-flight mass spectrometry method was used for the component characteration with the help of accurate molecular weights, fragmentation pathways, reported data, literatures and even some reference standards. Furthermore, in multiple-reaction monitoring mode, a high performance liquid chromatography coupled with quadrupole linear ion trap mass spectrometry method was developed and applied for simultaneous determination of the bioactive phytochemicals. As a result, a total of 56 components in GSDG were identified including 12 amino acids, 9 organic acids, 6 nucleosides and nucleobases, 6 flavonoids, 5 vitamins, 5 terpenoid lactones, 4 carbohydrates and 9 other compounds As for quantitative analysis, glutamic acid, asparatic acid, histidine, ginkgolide A, ginkgolide B, ginkgolide C, ginkgolide J, eucomic acid, N-(N-glucopyranosyl)-indoleacetylaspartate and N-(N-glucopyranosyl)-indoleacetylglutamate were selected as the analytes for quanlity marker of GSDG. After necessary validation tests, the developed quantitative method was successfully put into use for 10 batches of GSDG. In all batches, N-(N-glucopyranosyl)-indoleacetylaspartate was the richest phytochemical with the amount of 17.3-25.7 mg/g while ginkgolide J (0.0197-0.0335 mg/g) was determined to be the poorest. The study is supposed to exhibit a comprehensive chemical profiling and to provide some strong basis for preparation technology, quality control and even for action mechanism of GSDG, this novel form of Chinese medicine.

Energy Consumption Minimization with SNR Constraint for Wireless Powered Communication Networks.

The article addresses the energy consumption minimization problem in wireless powered communication networks (WPCNs) and proposes a time allocation scheme, named DaTA, which is based on the Different Target Simultaneous Wireless Information and Power Transfer (DT-SWIPT) scheme such that the wireless station can share the remaining energy after transmission to the Hybrid Access Point (HAP) to those who have not transmitted to the HAP to minimize the energy consumption of the WPCN. In addition to proposing a new frame structure, the article also considers the Signal-to-Noise (SNR) constraint to guarantee that the HAP can successfully receive data from wireless stations. In the article, the problem of minimization of energy consumption is formulated as a nonlinear programming model. We employ the SQP (Sequential Quadratic Programming) algorithm to figure out the optimal solution. Moreover, a heuristic method is proposed as well to obtain a near-optimal solution in a shorter time. The simulation results showed that the proposed scheme outperforms the related work in terms of energy consumption and energy efficiency.

Prevalence and associated factors of sexting among Taiwanese adolescents.

This study utilized a large-scale representative sample to explore the prevalence of sexting and its associated factors among adolescents in Taiwan. A total of 12,954 students in grade 5-12 countrywide were randomly selected to answer the sexting module of an online survey. 13.7% of the respondents reported having ever received sexts on cellphone, and 2.0% had sent sexts to others. The prevalence was higher among older adolescents. Gender differences were also found, in which female students were more likely to receive sexts (15.8% vs. 11.7%), while male students were at higher risk of sending sexts to others (2.9% vs. 1.1%). A series of hierarchical logistic regression were further performed to examine the associations between potential factors and receiving/sending sexts as the outcome variables. Age, gender, and time spending on texting were significantly associated with receiving and ending sexts. Online respect was found positively associated with receiving sexts but negatively associated with sending them. Privacy awareness was found not significantly associated with sexting. As the first national survey on this growing issue in Taiwan, the results of the present study highlighted the existence of sexting among local youth. Practice and policy implications were discussed.

[Characterizations of soil enzyme activities and stoichiometry in three subtropical forest stands]. / äºšçƒ­å¸¦ä¸‰ç§æž—åˆ†åœŸå£¤é ¶æ´»æ€§å’Œé ¶åŒ–å­¦è®¡é‡æ¯”ç‰¹å¾.

We conducted in a common garden experiment to explore the differences in soil enzyme activity, stoichiometry, and their influencing factors among a secondary Castanopsis carlesii forest, 10-year-old C. carlesii plantation, and Cunninghamia lanceolata plantation. The results showed that compared to the secondary forest, the soil organic carbon, total nitrogen, and dissolved organic carbon significantly decreased by 42.6%, 47.4%, and 60.9% in C. carlesii plantation, and by 42.9%, 36.7%, and 61.1% in C. lanceolata plantation. Soil microbial biomass C, microbial biomass N (MBN), and microbial biomass phosphorus decreased significantly by 40.6%, 35.5%, and 45.9% in C. carlesii plantation, and by 53.7%、56.4%, and 61.7% in C. lanceolata plantation. Compared to the secondary forest, soil enzymes activities in C. carlesii plantation did not change significantly, but in C. lanceolata plantation, the activities of ß-1,4-glucosidase and cellobiohydrolase significantly decreased by 51.2% and 59.8%, ß-N-acetyl glucosaminidase and acid phosphatase decreased significantly by 41.0% and 29.8%, and enzymatic C:N acquisition ratio and enzymatic C:P acquisition ratio significantly decreased by 11.3% and 7.7%, respectively. Results of redundancy analysis indicated that MBN and NO3--N were the primary factors influencing soil enzyme activity and enzymic stoichiometry. Collectively, there were significant differences in soil enzyme activity and microbial nutrient demands among different forest stands. Compared to secondary forests, the establishment of C. lanceolata plantations would intensify nutrient competition between plants and microbes, and exacerbate the N and P limitations for microbes.

6-D Object Pose Estimation Based on Point Pair Matching for Robotic Grasp Detection.

The 6-D pose estimation is a critical work essential to achieve reliable robotic grasping. Currently, the prevalent method is reliant on keypoint correspondence. However, this approach hinges on the determination of object keypoint locations, alongside their detection and localization in real scenes. It also employs the random sample consensus (RANSAC)-based perspective-n-point (PnP) algorithm to solve the pose. Yet, it is nondifferentiable and incapable of backpropagation with loss during the training phase. Alternatively, the direct regression method, while speedy and differentiable, falls short in terms of pose estimation performance, and thus needs enhancement. In view of these gaps, we investigate PPM6D, a new method for 6-D object pose estimation based on regression and point pair matching. Our methodology begins with a proposed cross-fusion module, designed to achieve the fusion and complementation of RGB features and point cloud features. Subsequently, an attention module adjusts the features of the object's 3-D model. Finally, we design a point pair matching module for effective matching of points and characteristics, resulting in an integral matching and fusion. PPM6D is extensively trained and tested utilizing benchmark datasets like LINEMOD, occlusion LINEMOD (LINEMOD-occ), YCB-Video, and T-LESS dataset. Experimental results prove that PPM6D can outperform many keypoint-based pose estimation methods, given its relatively rapid speed, thereby offering novel regression-based pose estimation ideas. When applied to real-world scenarios of object pose estimation tasks and grasp tasks of an actual Baxter robot, PPM6D demonstrates superior performance as compared to most alternatives.

Benchtop-Stable Carbyl Iminopyridyl NiII Complexes for Olefin Polymerization.

Design of catalysts for Ni-catalyzed olefin polymerization predominantly focuses on ligand design rather than the activation process when attempting to achieve a broader scope of polyolefin micro- and macrostructures. Air-stable alkyl-or aryl-functionalized NiII precatalysts were designed which eliminate the need of in situ alkylating processes and are activated solely by halide abstraction to generate the cationic complex for olefin polymerization. These complexes represent an emerging class of olefin polymerization catalysts, enabling the study of various cocatalysts forming either inner- or outer-sphere ion pairs. It is demonstrated that an organoboron cocatalyst activation produces a well-defined ion pair, which in contrast to ill-defined organoaluminum cocatalysts, can directly activate the complex by halide abstraction to yield comparatively higher molecular weight homo/copolymers. Under high ethylene pressure, broader branching densities and the gradual incorporation of short-chain branches were achieved, circumventing the need for elaborate ligand design and copolymerization with α-olefins. The underlying chain-walking mechanism and ion pair interactions were further elucidated by DFT calculations. A phenyl group on the bridging carbon functioned as a rotational barrier, producing higher molecular weight polymers compared to methyl-substituted analogs. Here, we provide a perspective to manipulate the iminopyridyl NiII system, leveraging ion pair interactions and ligand design to govern polyolefin molecular weights and microstructures.

Pseudohoeflea coraliihabitans sp. nov., a poly-ß-hydroxybutyrate-producing, halotolerant bacterium isolated from coral sediment in the Dapeng peninsula (Guangdong, China).

A Gram-stain-negative, strictly aerobic, motile, flagellated, rod-shaped, halotolerant, and poly-ß-hydroxyalkanoate-producing bacterium, designated DP4N28-3T, was isolated from offshore sediment surrounding hard coral in the Dapeng peninsula (Guangdong, PR China). Growth occurred at 15-35 °C (optimal at 30 °C), pH 6.0-9.5 (optimal at 6.0-7.0), and 0.0-30.0 % NaCl concentration (w/v, optimal at 0.0-2.0 %), showing halotolerance. Phylogeny based on 16S rRNA gene sequences, five housekeeping genes, and genome sequences identified Pseudohoeflea suaedae DSM 23348T (98.1 %, 16S rRNA gene sequence similarity) as the most related species to strain DP4N28-3T. Average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values between strain DP4N28-3T and P. suaedae DSM 23348T were all below the threshold of species demarcation. Major phenotypic differences were the flagella type and the limited sources of single carbon utilization by strain DP4N28-3T, which only included acetic acid, acetoacetic acid, d-glucuronic acid, and glucuronamide. Strain DP4N28-3T harboured the class I poly-ß-hydroxyalkanoate synthase gene (phaC) and produced poly-ß-hydroxybutyrate. The fatty acids were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c, 49.4 %) and C16 : 0 (13.4 %). The major cellular polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, and sulfoquinovosyl diacylglycerol. The respiratory quinone was Q-10. The results of the phylogenetic, genomic, phenotypic, and chemotaxonomic analysis indicated that the isolated strain represents the type strain of a novel species. Based on these results, strain DP4N28-3T (=MCCC 1K05639T=KCTC 82803T) is proposed as the type strain of the novel species Pseudohoeflea coraliihabitans sp. nov.

Development and evaluation of a second victim training course for nursing managers.

BACKGROUND: Most nursing managers are not fully aware of second victims and may not be able to provide support. Moreover, there are relatively few training courses for nursing managers about second victims. AIM: To describe the construction and evaluation of a second victim course for nursing managers. DESIGN: A single-group pretest-posttest study design was used. SETTING: A large comprehensive tertiary hospital with over 3000 beds in China. PARTICIPANTS: Forty-nine nursing managers who met the inclusion and exclusion criteria participated in this training. Sixteen clinical frontline nurses who experienced adverse events within three months following the training were also invited. METHODS: The course "Second Victim & Empathy Communication" was developed through a literature review and expert consultation and consisted of 4 unit modules: (1) adverse events & second victims, (2) the recovery trajectory of second victims, (3) second victim supportive resources, and (4) key strategies of empathy communication. A course evaluation questionnaire, an empathy communication questionnaire for nursing managers, a second victim evaluation questionnaire, and an open-ended question were used to measure the feasibility, acceptability and effectiveness of the course. RESULTS: >97.96 % of the nursing managers were satisfied with the course, >97.96 % had learned new knowledge, and >95.92 % had changed their behavior and attitudes toward second victims. Their levels of empathetic communication differed significantly before and after training (t = -2.170, P = 0.035). Among these nursing managers, twenty-six participants provided positive and meaningful feedback and suggestions to the course by answering an open-ended question. A total of 66.6 % to 100 % of second victims were satisfied with the empathetic communication behavior exhibited by nursing managers. CONCLUSION: The second victim training course is feasible and can be used for clinical training to enhance nursing managers' understanding of second victims and enhance their empathetic communication.

Self-stacked small molecules for ultrasensitive, substrate-free Raman imaging in vivo.

Raman spectroscopy using surface-enhanced Raman scattering (SERS) nanoprobes represents an ultrasensitive and high-precision technique for in vivo imaging. Clinical translation of SERS nanoprobes has been hampered by biosafety concerns about the metal substrates used to enhance Raman signals. We report a set of small molecules with bis-thienyl-substituted benzobisthiadiazole structures that enhance Raman signal through self-stacking rather than external substrates. In our technique, called stacking-induced charge transfer-enhanced Raman scattering (SICTERS), the self-stacked small molecules form an ordered spatial arrangement that enables three-dimensional charge transfer between neighboring molecules. The Raman scattering cross-section of SICTERS nanoprobes is 1350 times higher than that of conventional SERS gold nanoprobes of similar particle size. SICTERS outperforms SERS in terms of in vivo imaging sensitivity, resolution and depth. SICTERS is capable of noninvasive Raman imaging of blood and lymphatic vasculatures, which has not been achieved by SERS. SICTERS represents an alternative technique to enhance Raman scattering for guiding the design of ultrasensitive substrate-free Raman imaging probes.

MEMS-based meta-emitter with actively tunable radiation power characteristic.

We propose a meta-emitter based on micro-electro-mechanical system (MEMS) technology. The main structure of the meta-emitter unit cell is composed of four symmetrically split crosses of Au and SiO2 bilayer cantilevers. By changing the size of the cantilevers, this MEMS-based meta-emitter can realize the tunable perfect absorption, and the absorption spectrum is within the longwave infrared (LWIR) wavelength from 8.90 to 11.90 µm. When the surface temperature of the meta-emitter rises, the electrothermal actuation mechanism is performed through the different thermal expansion coefficient (TEC) of the bilayer cantilevers. Therefore, the cantilevers will be bent downward and the bending height of the cantilevers decreases linearly. In such case, the peak value of thermal radiation power can be tuned from the wavelength of 9.52 µm to 10.48 µm when the temperature of meta-emitter is increased from 293 to 1290 K. This proposed MEMS-based meta-emitter is an excellent LWIR light source and has potential application prospects in gas sensing, infrared spectroscopy analysis, medical care and so on.

Microelectromechanical System-Based Reconfigurable Terahertz Metamaterial for Polarization Filter, Switch, and Logic Modulator Applications.

The terahertz (THz) metamaterials integrated with microelectromechanical systems (MEMS) have led to the realization of dynamic control in amplitude, phase, polarization, and spin angular momentum of the THz wave. In this study, we demonstrate an MEMS-based reconfigurable THz metamaterial (RTM) composed of a split ring resonator (SRR) for real-time modulation of THz wave. By gradually increasing the polarization angle of the incident THz wave, the resonant frequency of SRR switches from 0.74 to 1.16 THz, and the maximum modulation depth is more than 70%. When the MEMS-based RTM is actuated by different DC bias voltages, the polarization-dependent transmission intensity and resonant frequency of the device can be actively tuned. MEMS-based RTM shows logical function characteristics that can be used for logic modulators by performing the driving voltages and polarization states as 2-bit input signals and quantizing the transmission response as "on" and "off" states. The logic gates of "NAND" are at 0.439 THz and "AND" is at 0.732 THz. These results offer potential applications for the proposed MEMS-based RTM in tunable and reconfigurable polarization filters, optical switches, programmable logic modulators, and so on.