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Bis-benzimidazole derivative (BBM) molecule, consisting of two 2-(2’-Hydroxyphenyl) benzim-idazole (HBI) halves, has been synthesized and successfully utilized as a ratiometric fluorescence sensor for the sensitive detection of Cu2+ based on enol-keto excited state intramolecular proton transfer (ESIPT). In this study, we strategically implement femtosecond stimulated Raman spec-troscopy and several time-resolved electronic spectroscopies, aided by quantum chemical calcula-tions to investigate the detailed primary photodynamics of BBM molecule. The results demonstrate that the ESIPT from BBM-enol* to BBM-keto* was observed in only one of HBI halves with a time constant of 300 fs, after that, the rotation of the dihedral angle between two HBI halves generate a planarized BBM-keto* isomer in 3 ps, leading to dynamics red shift of BBM-keto* emission.

For post-Fukushima nuclear power plants, there has been interested in accident-tolerant fuel (ATF) since it has better tolerant in the event of a severe accident. The fully ceramic microencapsulated (FCM) fuel is one kind of the ATF materials. In this study, the small modular pressurized water reactor (PWR) loading with FCM fuels was investigated, and the modified Constant Axial shape of Neutron flux, nuclide number densities and power shape During Life of Energy producing reactor (CANDLE) burnup strategy was successfully applied to such compact reactor core. To obtain ideal CANDLE shape, it’s necessary to set the infinity or enough length of the core height, but that is impossible for small compact core setting infinity or enough length of the core height. Due to the compact and finite core, the equilibrium state can only be maintained short periods and is not obvious, other than infinitely long active core to reach the long equilibrium state for ideal CANDLE. Consequently, the modified CANDLE shape would be presented. The approximate characteristics of CANDLE burnup are observed in the finite and compact core, and the power density and fuel burnup are selected as main characteristic of modified CANDLE burnup. In this study, firstly, lots of optimization schemes were discussed, and one of optimization schemes was chosen at last to demonstrate the modified CANDLE burnup strategy. Secondly, for chosen compact small rector core, the modified CANDLE burnup strategy is applied and presented. Consequently, the new characteristics of this reactor core can be discovered both in ignition region and in fertile region. The results show that application of CANDLE burnup strategy to small modular PWR loading with FCM fuels suppresses the excess reactivity effectively and reduces the risk of small PWR reactivity-induced accidents during the whole core life, which makes the reactor control more safety and simple.

This article proposes a nameplate recognition method based on the least-squares method and deep learning algorithm character feature fusion. This method extracts the histogram of the edge direction of the character and constructs the histogram feature vector based on the wavelet transform deep learning algorithm. We use classifier training for the text recognition of the nameplate to segment the text into individual characters. Then, we extract the character features to build a template. Experiments prove that the algorithm meets the practical application needs of nameplate identification of power equipment and achieves the design goals.

Technology standards are considered important tools for increasing bargaining power and licensing revenues by combining the strategies of firms with the standard-setting organizations (SSOs) standardization processes. The essential patents declared by members of the SSOs play a critical role in such standardization processes. Some former researchers have found that, when using network analysis for measuring the knowledge positions in the “main-path” of standards-based markets, the essential patents did not match very well with the actual knowledge positions of the firms, in most cases. In this paper, we focus on the essential patents declared by the member firms in JTC1, an SSO that provides a standards development environment related to the development of the worldwide information and communication technology (ICT) standards for business and consumer applications, and that employs social network analysis techniques to investigate the knowledge positions of the patents, not only in the “main-path” discussed in the earlier literature, but also in the brokerage processes. We found that the brokerage-process approach helped us to better understand the roles of the essential patents that dominate transactions, relations, and the exchange of knowledge in the patent citation network than that of the main-path. Our findings suggest that claiming essentiality depends on the strategic behavior not only of the patents’ owners, but also of the SSOs.

Large Stokes shift (LSS) red fluorescent proteins (RFPs) are highly desirable for bioimaging advances. The RFP mKeima, with coexisting cis- and trans-isomers, holds significance as an archetypal system for LSS emission due to excited-state proton transfer (ESPT), yet the mechanisms remain elusive. We implemented femtosecond stimulated Raman spectroscopy (FSRS) and various time-resolved electronic spectroscopies, aided by quantum calculations, to dissect the cis- and trans-mKeima photocycle from ESPT, isomerization, to ground-state proton transfer in solution. This work manifests the power of FSRS with global analysis to resolve Raman fingerprints of intermediate states. Importantly, the deprotonated trans-isomer governs LSS emission at 620 nm, while the deprotonated cis-isomer's 520 nm emission is weak due to an ultrafast cis-to-trans isomerization. Complementary spectroscopic techniques as a table-top toolset are thus essential to study photochemistry in physiological environments.

Background The cell cycle arrest markers tissue inhibitor metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been identified as potential biomarkers of acute kidney injury (AKI) in critically ill adults in intensive care units and cardiac surgery-associated AKI (CSA-AKI). However, the clinical impact on all-cause AKI remains unclear. Here, we report a meta-analysis performed to evaluate the predictive value of this biomarker for all-cause AKI. Methods The PubMed, Cochrane, and EMBASE databases were systematically searched up to April 1, 2022. We used the Quality Assessment Tool for Diagnosis Accuracy Studies (QUADAS-2) to assess the quality. We extracted useful information from these studies and calculated the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). Results Twenty studies with 3625 patients were included in the meta-analysis. The estimated sensitivity of urinary [TIMP-2]ⅹ[IGFBP7] in the diagnosis of all-cause AKI was 0.79 (95% CI:0.72, 0.84), and the specificity was 0.70 (95% CI:0.62, 0.76). The value of urine [TIMP-2]ⅹ[IGFBP7] in the early diagnosis of AKI was assessed using a random effects model. The pooled positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 2.6 (95% CI:2.1, 3.3), 0.31 (95% CI:0.23, 0.40), and 8 (95% CI:6, 13), respectively. The AUROC was 0.81 (95% CI: 0.78–0.84). No significant publication bias was observed in eligible studies. Subgroup analysis indicated that the diagnostic value was related to the severity of AKI, time measurement, and clinical setting. Conclusion This study shows that urinary [TIMP-2]ⅹ[IGFBP7] is a reliable effective predictive test for all cause-AKI. However, whether and how urinary [TIMP-2]ⅹ[IGFBP7] can be used in clinical diagnosis still requires further research and clinical trials.

The anti-Kasha process provides the possibility of using high-energy excited states to develop novel applications. Our previous research (Nature communications, 2020, 11, 793) has demonstrated a dual-emission anti-Kasha-active fluorophore for bioimaging application, which exhibits near-infrared emissions from the S-1 state and visible anti-Kasha emissions from the S-2 state. Here, we applied tunable blue-side femtosecond stimulated Raman spectroscopy (FSRS) and transient absorption spectroscopy, assisted by quantum calculations, to reveal the anti-Kasha dual emission mechanism, in which the emergence of two fluorescing states is due to the retardation of internal conversion from the S-2 state to the S-1 state. It has been demonstrated that the facts of anti-Kasha high-energy emission are commonly attributed to a large energy gap between the two excited states, leading to a decrease in the internal conversion rate due to a poor Franck-Condon factor. In this study, analysis of the calculation and FSRS experimental results provide us further insight into the dual-emission anti-Kasha mechanism, where the observation of hydrogen out-of-plane Raman modes from FSRS suggested that, in addition to the energy-gap law, the initial photoinduced molecular conformational change plays a key role in influencing the rate of internal conversion.

Nomex honeycomb core has been widely applied in aerospace industries due to its superior strength and rigidity. However, the machining defects of honeycomb core can deteriorate the bonding strength between honeycomb core and connective face sheet. This paper investigates the tearing defects formatted in milling process of Nomex honeycomb core. Firstly, a cutting force model is proposed to predict the milling forces under various tool entrance angles. Then, finite element simulation for machining honeycomb wall is conducted to reveal the formation mechanism of tearing defects. The accuracy of the model is verified by a group of experiments under different entrance angles and the relative error is below 25% in 1-direction and 20% in 2-direction. It is found that the formation of tearing defects is closely related to the deformation of honeycomb wall and the component of cutting force in direction parallel to wall. The tool entrance angle can be thus optimized based on the reduction of tearing defects. The optimized entrance angle of double wall is among 40° and 70°.

Whereas technical standards and Standard Setting Organizations (SSOs) are omnipresent and essential to mass production and communications, relatively little is formally known about the propensity of firms’ decisions to belong to certain SSOs. An understanding of such propensities can explain why some firms join SSOs (and others do not) and have implications for the regulation of SSOs. This paper uses a social network analysis technique to categorize/place firms in SSO communities and then empirically analyzes their propensities to belong to SSOs. We concentrate our study on standard setting organizations’ features and their intellectual property rights (IPR) policies such as licensing rules, disclosure requirements, as well as the features of the decision process of standards. Using data on more than 1060 member firms as participants in 28 SSOs, we are able to uniquely graph the membership of firms in SSOs by highlighting some important characteristics through community detection. The results provide some novel insights into why firms might choose certain SSO communities over others.

Understanding how the conformational change of conjugated molecules with acceptor-donor-acceptor (A-D-A) architecture affects their physical and optoelectronic properties is critical for determining their ultimate performance in organic electronic devices. Here, we utilized femtosecond transient absorption, time-resolved upconversion photoluminescence spectroscopy, and tunable femtosecond-stimulated Raman spectroscopy, aided by quantum chemical calculations, to systematically investigate the excited state structural dynamics of the intramolecular charge transfer of the tetramethoxy anthracene-based fluorophore 2,3,6,7-tetramethoxy 9,10-dibenzaldehydeanthracene (AnDA) and its derivative 2,3,6,7-tetramethoxy 9,10-diphenylanthracene (TMDPAn) in chloroform. In the AnDA molecule, the tetramethoxy anthracene and benzaldehyde moieties exhibit a strong ability to donate and withdraw electrons. Upon photoexcitation, AnDA shows intriguing ultrafast fluorescence switch-on and red shift dynamics on charge transfer states, and the temporal evolution of AnDA recorded by ultrafast spectroscopy reveals a dynamic picture of two-step intramolecular charge transfer assisted by ultrafast conformational changes and solvation processes. Removing the aldehyde group from TMDPAn significantly decreases the electron pulling capacity of the phenyl unit and disables charge transfer characteristics.

The knowledge and innovation generated by researchers at universities is transferred to industries through patent licensing, leading to the commercialization of academic output. In order to investigate the development of Chinese university–industry technology transfer and whether this kind of collaboration may affect a firm’s innovation output, we collected approximately 6400 license contracts made between more than 4000 Chinese firms and 300 Chinese universities for the period between 2009 and 2014. This is the first study on Chinese university–industry knowledge transfer using a bipartite social network analysis (SNA) method, which emphasizes centrality estimates. We are able to investigate empirically how patent license transfer behavior may affect each firm’s innovative output by allocating a centrality score to each firm in the university–firm technology transfer network. We elucidate the academic–industry knowledge by visualizing flow patterns for different regions with the SNA tool, Gephi. We find that innovation capabilities, R&D resources, and technology transfer performance all vary across China, and that patent licensing networks present clear small-world phenomena. We also highlight the Bipartite Graph Reinforcement Model (BGRM) and BiRank centrality in the bipartite network. Our empirical results reveal that firms with high BGRM and BiRank centrality scores, long history, and fewer employees have greater innovative output.

Accurate measuring temperature-dependent thermal conductivities of (Ti,Al)N ceramic coating is important to quantitatively analyze the thermal effects of (Ti,Al)N ceramic coating on the heat generation and heat transfer during cutting process by PVD (Ti,Al)N coated cemented tools. In this paper, the temperature-dependent thermal conductivities of PVD Ti0.55Al0.45N ceramic coating with coating thickness of 2 µm in the temperature ranges of 25–500 °C are measured by time domain thermo-reflectance method. Firstly, the detailed deposition process and microstructure characterization of PVD Ti0.55Al0.45N ceramic coating are presented. Secondly, the measuring principle and measuring procedure of PVD ceramic coating thermal conductivity with the time domain thermo-reflectance are proposed. Then, the measured thermal properties of substrate are used in the calculation algorithm to obtain the thermal conductivity of Ti0.55Al0.45N ceramic coating at the specific temperature, which can eliminate the variation influences of substrate thermal properties with temperature. Lastly, the obtained thermal conductivities of PVD Ti0.55Al0.45N ceramic coating are verified to be increased with the increase of temperature in the temperature ranges of 25–500 °C. The relationship between the thermal conductivity of PVD Ti0.55Al0.45N coating and temperature can be represented by quadratic polynominal equation. The applied time domain thermo-reflectance method is useful for measuring the temperature-dependent thermal conductivities of similar ceramic coatings in the temperature ranges of 25–500 °C.

Using patent citations as an indicator of knowledge flows, this paper examines the effects of firms’ global patent social networks on knowledge flows from business method software patents. Patent social networks are considered along several dimensions, including relative centrality, structural equivalence and brokerage roles. Identifying 19,385 software patents applications to the USPTO by 37 countries during 1995–2012, results show that firms positioned with a relative centrality or situated within the same structural equivalent cluster have more citations to their counterpart firms’ patents. Further, among the different brokerage roles, we find positive promotion to knowledge transfer when the citing and cited firms both serve the role of an itinerant as well as that of a gatekeeper/representative, while firms that act as gatekeeper/representative (alone) cite less patents from firms that do not enact this kind of a role. These unique insights provide a better understanding of channels of knowledge transmission and have implications for the pace of technological change.

Remote sensing-based geological exploration is based on identifying and analyzing spectral features of minerals and rocks. Although an abundance of high quality multispectral remote sensing datasets is available, no appropriate method of full-band absorption feature extraction has been proposed for these datasets. In this work, we developed a new method, Virtual Band Continuum Removal (VBCR), for the extraction of absorption feature spectra from multispectral datasets. By setting the nodes of the continuum on virtual bands instead of the real bands, the proposed method is an improved approach for preserving the weak absorption features in multispectral datasets. VBCR was compared with a state of the art approach on both laboratory data and real image data, and the experimental results indicated the efficacy of the proposed method.

This paper has two main contributions. The first is a new linear logical semantics of causal attack trees in four-valued truth tables. Our semantics is very simple and expressive, supporting specializations, and supports the ideal semantics of causal attack trees, and partially supporting the filter semantics of causal attack trees. Our second contribution is Lina, a new embedded, in Haskell, domain specific functional programming language for conducting threat analysis using attack trees. Lina has many benefits over existing tools; for example, Lina allows one to specify attack trees very abstractly, which provides the ability to develop libraries of attack trees, furthermore, Lina is compositional, allowing one to break down complex attack trees into smaller ones that can be reasoned about and analyzed incrementally. Furthermore, Lina supports automatically proving properties of attack trees, such as equivalences and specializations, using Maude and the semantics introduced in this paper.

In this paper we introduce Commutative/Non-Commutative Logic (CNC logic) and two categorical models for CNC logic. This work abstracts Benton's Linear/Non-Linear Logic by removing the existence of the exchange structural rule. One should view this logic as composed of two logics; one sitting to the left of the other. On the left, there is intuitionistic linear logic, and on the right is a mixed commutative/non-commutative formalization of the Lambek calculus. Then both of these logics are connected via a pair of monoidal adjoint functors. An exchange modality is then derivable within the logic using the adjunction between both sides. Thus, the adjoint functors allow one to pull the exchange structural rule from the left side to the right side. We then give a categorical model in terms of a monoidal adjunction, and then a concrete model in terms of dialectica Lambek spaces., Comment: In Proceedings Linearity-TLLA 2018, arXiv:1904.06159

In this paper we introduce novel time-resolved photoluminescence spectroscopy called femtosecond two pulses induced stimulated emission spectroscopy, in which the generated nonlinear photoluminescence signal was used to identify the ultrafast dynamics of stimulated emission process in the semiconductor material. By employing two collinear fundamental femtosecond laser beams, we systematically investigated time-resolved multiphoton-induced amplified spontaneous emission in ZnO single crystal. Our results demonstrate the feasibility of this technique with the advantage of easy setup and high time resolution.

As one of the most fundamental processes, proton transfer reaction plays an important role in chemical and biological process, and to reveal the choreography of the proton motion intra- and intermolecularly, a spectroscopic technique capable of capturing molecular structural dynamics of excited-state proton transfer motions on an intrinsic time scale is needed. In this study, We utilize wavelength-tunable femtosecond stimulated Raman spectroscopy with a time resolution of ~100 fs, spectral resolution of 15 cm–1 and spectral range of 400 cm–1—1800 cm–1, combined with traditional transient absorption spectroscopywith a time window between 0 and 600 ps to simultaneously achieve reaction dynamics for transient reactant and product of the photoacid pyranine (8-hydroxypyrene1, 3, 6-trisulfonic acid, HPTS) molecules undergoing excited-state proton transfer reaction in complex with water and acetate molecules. Marker bands attributed to the deprotonated form of HPTS in a frequency range from 400 cm–1 to 1700 cm–1 are obtained under the excitation of 400 nm laser pulses. The marker band at 1516 cm–1, which is assigned to phenolic ring carbon carbon double band stretching accompanied with carbon hydrogen in-plane rocking motions, exhibits complex rise and decay dynamics. The simultaneously observed excited-state Raman mode at 920 cm–1 which is assigned to the excited carbon-carbon single bond stretch mode in the protonated acetic acid root molecule, helps us to clearly resolve the reaction rates of excited-state proton transfer. Based on the multi-exponential fitting results, the dynamics of excited-state Raman mode at 920 cm–1 exhibits bi-exponential processes with time constants of ~470 fs and ~3 ps. The ultrafast time component indicates that the excited-state proton transfer originates from an HPTS-acetate complex, indicating that part of the ground-state HPTS molecules are in the “tight” hydrogen bonding configuration that can quickly shift the excited-state proton charge toward the acetate acceptor molecule through a direct hydrogen bond. The second slower time component implies a significant subpopulation of HPTS in the ground state, i.e. hydrogen bonds to an acetate ion via an intervening water molecule, and upon photo excitation, the proton transfers to the water solvent before proton is picked up by the acetate ion.

Service-oriented computing (SOC) is a popular software paradigm that is widely employed in IT industry. SOC uses "services" as the unit of functionality of a software application. The massive wave of SOC applications involves considerable energy consumption of servers, which should not be ignored in large-scale computing environment. When a service requirement can be answered by several web services, the energy consumption for each service to reply to the service request may be different. When this happens, web service selection (WSS) is often required to choose appropriate services to maximize global energy efficiency of SOC applications. Accordingly, this paper proposes a Virtual Power Meter Supported Power Consumption Prediction method for WSS (VPMSPCP). VPMSPCP facilitates choosing appropriate services to minimize wasteful electrical energy from the overall environment of SOC applications. According to our empirical proof, there is a correlation between the power consumption of a service and the status of the server where this service resides. We take advantage of this discovery to develop VPMSPCP by combining a ridge regression model with a well-known web service power modeling method. There are mainly two steps to establish VPMSPCP. First, we develop a virtual power meter (VPM) for each server. VPM is used to estimate the average power of a server under a certain status. Second, we apply the VPM to develop VPMSPCP which estimates power consumption of a web service according to the current status of the corresponding servers. Experiments show that VPMSPCP performs well in improving energy saving in WSS.

Broadening of white-light continuum is observed by filamentation of near-infrared femtosecond laser pulses with peak power exceeding the megawatt level in BK7 glass with the presence of the zero-dispersion point. The simulated results show that, due to the low dispersion at the zero-dispersion point, the broadening of white-light continuum can be wider and the filament can persist in propagating stably longer distance.

We experimentally and theoretically demonstrate that the property (odd or even) of generated harmonics can be selected by manipulating the macroscopic phase-matching conditions based on a three-color laser field. Only odd or even harmonics can be made dominant by changing the focal position and adjusting the gas pressure. These results indicate that the odd-even property of the generated harmonics can be controlled by using the multi-color laser field with macroscopic phase-matching.