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We present neutrino-transport hydrodynamic simulations of electron-capture supernovae (ECSNe) in flash with new two-dimensional (2D) collapsing progenitor models. These progenitor models feature the 2D modelling of oxygen-flame propagation until the onset of core collapse. We perform axisymmetric simulations with six progenitor models that, at the time of collapse, span a range of propagating flame front radii. For comparison, we also perform a simulation with the same set-up using the canonical, spherically symmetrical progenitor model n8.8. We found that the variations in the progenitor models inherited from simulations of stellar evolution and flame propagation do not significantly alter the global properties of the neutrino-driven ECSN explosion, such as the explosion energy (∼1.36–1.48 × 1050 erg) and the mass (∼0.017–0.018 M⊙) and composition of the ejecta. Due to aspherical perturbations induced by the 2D flame, the ejecta contains a small amount (≲1.8 × 10−3 M⊙) of low- Y e (0.35 < Y e < 0.4) component. The baryonic mass of the protoneutron star is ∼1.34 M⊙ (∼1.357 M⊙) with the new (n8.8) progenitor models when simulations end at ∼400 ms and the discrepancy is due to updated weak-interaction rates in the progenitor evolutionary simulations. Our results reflect the nature of ECSN progenitors containing a strongly degenerate oxygen–neon–magnesium (ONeMg) core and suggest a standardized ECSN explosion initialized by ONeMg core collapse. Moreover, we carry out a rudimentary three-dimensional simulation and find that the explosion properties are fairly compatible with the 2D counterpart. Our paper facilitates a more thorough understanding of ECSN explosions following the ONeMg core collapse, though more three-dimensional simulations are still needed. [ABSTRACT FROM AUTHOR]

We study the consequences of a hadron-quark phase transition (PT) in failing core-collapse supernovae (CCSNe) that give birth to stellar-mass black holes (BH). We perform a suite of neutrino-transport general-relativistic hydrodynamic simulations in spherical symmetry with 21 progenitor models and a hybrid equation of state (EoS) including hadrons and quarks. We find that the effect of the PT on the CCSN postbounce dynamics is a function of the bounce compactness parameter. For , the PT leads to a second dynamical collapse of the protocompact star (PCS). While BH formation starts immediately after this second collapse for models with , the PCS experiences a second bounce and oscillations for models with. These models emit potent oscillatory neutrino signals with a period of ∼1 ms for tens of milliseconds after the second bounce, which can be a strong indicator of the PT in failing CCSNe if detected in the future. However, no shock revival occurs and BH formation inevitably takes place in our spherically symmetric simulations. Furthermore, via a diagram of mass-specific entropy evolution of the PCS, the progenitor dependence can be understood through the appearance of a third family of compact stars emerging at large entropy induced by the PT. [ABSTRACT FROM AUTHOR]

Using Epstein‐Barr virus (EBV)‐induced cancer cells and HeLa cells as a comparative study model, a novel and safe dual‐EBV‐oncoproteins‐targeting pH‐responsive peptide engineering, coating, and guiding approach to achieve precision targeting and treatment strategy against EBV‐associated cancers is introduced. Individual functional peptide sequences that specifically bind to two overexpressed EBV‐specific oncoproteins, EBNA1 (a latent cellular protein) and LMP1 (a transmembrane protein), are engineered in three different ways and incorporated with a pH‐sensitive tumor microenvironment (TME)‐cleavable linker onto the upconversion nanoparticles (UCNP) NaGdF4:Yb3+, Er3+@NaGdF4 (UCNP‐Pn, n = 5, 6, and 7). A synergistic combination of the transmembrane LMP1 targeting ability and the pH responsiveness of UCNP‐Pn is found to give specific cancer differentiation with higher cellular uptake and accumulation in EBV‐infected cells, thus a lower dose is needed and the side effects and health risks from treatment would be greatly reduced. It also gives responsive UC signal enhancement upon targeted dual‐protein binding and shows efficacious EBV cancer inhibition in vitro and in vivo. This is the first example of simultaneous imaging and inhibition of two EBV latent proteins, and serves as a blueprint for next‐generation peptide‐guided precision delivery nanosystem for the safe monitoring and treatment against one specific cancer. [ABSTRACT FROM AUTHOR]

We developed a H 2 S-activatable lanthanide-based nanosensor with both upconverting luminescence and NIR-II fluorescence for the fast, selective and ultrasensitive detection of H 2 S. [Display omitted] • Ultrasensitive and rapid detection towards H 2 S was achieved based on a upconversion nanosensor. • The nanosensor can detect H 2 S through NIR-II fluorescence of the in-situ formed Ag 2 S. • The designed nanosensor could facilely achieve H 2 S detection with ultralow LOD of 0.93 ng/mL. Hydrogen sulfide (H 2 S), a third gas signaling molecule, is considered to play a vital role in the development and treatment of diseases. To elucidate the intricate role of H 2 S in the organism and its participation in disease processes, there is an urgent need to visualize the dynamics of H 2 S. However, most currently available molecular probes have limitations in terms of sensitivity, specificity, and precision. In this study, the safe and biocompatible upconversion nanosensor NaYF 4 :Yb3+, Tm3+@NaYF 4 anchored with Ag 2 O was successfully fabricated for H 2 S detection with an ultralow detection limit at 0.93 ng/mL. NaYF 4 :Yb3+, Tm3+@NaYF 4 @Ag 2 S is formed through in situ sulfuration reaction, and second near-infrared (NIR-II) fluorescence can be recorded upon the presence of H 2 S under 808 nm excitation. The results demonstrate the exceptional detection linearity and high specificity for H 2 S quantification. Additionally, NaYF 4 :Yb3+, Tm3+@NaYF 4 @Ag 2 O possesses a safe nature in normal and cancer cells. This nanosensor presents a NIR fluorescence imaging strategy for highly sensitive and specific detection of H 2 S, which has promises to be a practical tool for biomedical applications. [ABSTRACT FROM AUTHOR]

Stars with ∼8–10 M⊙ evolve to form a strongly degenerate ONeMg core. When the core mass becomes close to the Chandrasekhar mass, the core undergoes electron captures on 24Mg and 20Ne that induce an electron-capture supernova (ECSN). In order to clarify whether the ECSN leads to a collapse or thermonuclear explosion, we calculate the evolution of an 8.4 M⊙ star from the main sequence until the oxygen ignition in the ONeMg core. We apply the latest electron-capture rate on 20Ne, including the second forbidden transition, and investigate how the location of the oxygen ignition (center or off-center) and the Ye distribution depend on the input physics and the treatment of the semiconvection and convection. The central density when the oxygen deflagration is initiated, ρc,def, can be significantly higher than that of the oxygen ignition thanks to the convection, and we estimate. We perform two-dimensional simulations of the flame propagation to examine how the final fate of the ONeMg core depends on the Ye distribution and ρc,def. We find that the deflagration starting from leads to a collapse (thermonuclear explosion). Since our estimate of ρc,def exceeds this critical value, the ONeMg core is likely to collapse, although further studies of the convection and semiconvection before the deflagration are important. [ABSTRACT FROM AUTHOR]

The free vibration analysis of the functionally graded (FG) double curved shallow shell structures with general boundary conditions is investigated by an improved Fourier series method (IFSM). The material properties of FG structures are assumed to vary continuously in the thickness direction, according to the four graded parameters of the volume distribution function. Under the current framework, the displacement and rotation functions are set to a spectral form, including a double Fourier cosine series and two supplementary functions. These supplements can effectively eliminate the discontinuity and jumping phenomena of the displacement function along the edges. The formulation is based on the first-order shear deformation theory (FSDT) and Rayleigh-Ritz technique. This method can be universally applied to the free vibration analysis of the shallow shell, because it only needs to change the relevant parameters instead of modifying the basic functions or adapting solution procedures. The proposed method shows excellent convergence and accuracy, which has been compared with the results of the existing literatures. Numerous new results for free vibration analysis of FG shallow shells with various boundary conditions, geometric parameter, material parameters, gradient parameters, and volume distribution functions are investigated, which may serve as the benchmark solution for future researches. [ABSTRACT FROM AUTHOR]

We developed the functionalized upconversion nanoprobe with ultrasensitive and responsive properties for glucose detection, the responsive emission and satisfactory differentiated performances are observed in situ and in vitro. [Display omitted] • Ultrasensitive and rapid detection strategy of glucose was constructed based on lanthanide-doped upconversion nanoprobe. • The functionalized nanoprobe can distinguish cancer cells from normal cells by in vitro emission intensity via optical bioimaging. • The designed nanoprobe would facilely achieve glucose detection in situ and in vitro with ultralow detection limit. Various approaches for detecting glucose concentration in real time are emerging at a breakneck pace. Glucose metabolism is closely linked to severe pathological events, which would either cause or predispose many progressive diseases in human. Herein, hydrophilic upconversion nanoprobes NaGdF 4 : Yb3+, Er3+@Ag anchored with glucose oxidase (GOx) for glucose detection with lower detection limits have been efficaciously constructed. In the upconversion nanoprobes, NaGdF 4 : Yb3+, Er3+ cores, and Ag layers act as energy donors and effective quenchers, respectively, through energy transfer. Moreover, the layer of Ag may disintegrate by H 2 O 2 in the presence of glucose when glucose oxidase anchoring on the exterior of NaGdF 4 : Yb3+, Er3+@Ag nanoprobes, which leads to the phenomenon of upconverting emission recovery. Additionally, NaGdF 4 : Yb3+, Er3+@Ag-GOx has an ultralow detection limit of 1.77 μmol L−1 on glucose detection, and it can achieve optical bioimaging to distinguish cancer cells from normal cells. As a result, the NaGdF 4 : Yb3+, Er3+@Ag nanoprobes could be expanded to detect diverse H 2 O 2 -involved analytes. Overall, this nanoprobe has promising potential to be a compelling tool for the biomedical applications. [ABSTRACT FROM AUTHOR]

We developed a novel nanocomposite consisted of UCNP, tetraphenyl porphyrin and GOx for detecting glucose based on upconversion luminescence quenching recovery, and it can achieve glucose detection and carcinoma cells inhibition in vitro simultaneously. [Display omitted] • Highly sensitive and rapid detection of glucose was established based on upconversion luminescence quenching recovery. • The functionalized nanoprobe with tetraphenyl porphyrin was facilely developed and it possessed dual excitation wavelength. • The designed nanocomposite could achieve glucose detection and carcinoma cells inhibition in vitro simultaneously. In this work, we introduce the upconverting detection nanoprobes UCNP-TPP-GOx based on the upconversion quenching effect recovery for the ultrasensitive, expeditious, quantitative, and in vitro cellular detection of glucose. This nanoplatform consists of upconversion nanoparticles (UCNP), tetraphenyl porphyrin (TPP) and glucose oxidase (GOx). In a nutshell, UCNPs core are linked with cancer-killing TPP via condensation reaction to form UCNP-TPP, subsequently, UCNP-TPP-GOx is fabricated through glucose oxidase (GOx) decoration on the surface of the UCNP-TPP. Additionally, UCNP-TPP-GOx possesses characteristic photophysical property and it is highly suitable for optical detection. Furthermore, UCNP-TPP-GOx shows excellent selectivity toward glucose after only 3-min coincubation and the limit of detection (LOD) for the glucose is calculated as low as 0.86 μg mL−1. Moreover, the differentiation between cancer and normal cells through in vitro confocal imaging is achieved due to the large differences of glucose level in them. More importantly, the significant inhibition on carcinoma cell growth is realized by simply switching to the specific excitation wavelength, followed by the generation of toxic singlet oxygen from TPP moiety. Hence, the developed nanoprobes presenting new possibilities for on-site rapid glucose detection and concurrent theranostics in vitro in a "one stone two birds" strategy. [ABSTRACT FROM AUTHOR]

Proponents of distributive justice with regard to energy hold that every household has the right to affordable access to energy. However, when passively participating in clean energy reform policies, households, and especially low-income households, are often forced to use energy beyond the scope of affordability, resulting in distributive injustice. However, research on the quantitative estimation of injustice in energy distribution is still rare. In this paper, an evaluation model of energy vulnerability and distributive justice is established through the "reverse deduction method," and the change value of energy vulnerability before and after energy reform is used to calculate the loss value of distributive justice, which is used as the basis for energy policy evaluation. Taking the policy of replacing coal with natural gas for rural heating in Gaocheng District, Hebei Province, China as a case study, the value of lost distributive justice is calculated. The results show that 34.51% of households experienced distributive injustice after the energy reform, while 19.34% of households improved their energy vulnerability and achieved energy justice through energy subsidy policies. However, 46.15% of households were able to adapt to the energy reform independently without subsidies, which indicates a waste of resources in the energy subsidy policy. The policy implication of these results is that differentiated energy subsidy policies should be implemented according to household energy vulnerability, so as to maximize the policy benefits on the premise of ensuring justice in household energy distribution and minimizing injustice. The empirical study proves that the method of assessing injustice in energy distribution based on the "reverse deduction method" of energy vulnerability is feasible and a new attempt. • The passive participation of low-income households in clean energy reform policies results in distributive injustice. • Apply the vulnerability framework to calculate energy distribution injustice. • The implementation of differentiated subsidies can effectively improve the vulnerability of rural households energy poverty. • It is feasible and a new attempt to measure energy distributive injustice by using the "reverse deduction method". [ABSTRACT FROM AUTHOR]

Epstein‐Barr virus (EBV) is a common human‐infected virus related to many diseases and cancers. Recently, some peptides have been found to serve targeting and therapeutic roles by inhibiting EBNA1, an oncoprotein of the EBV. We herein report the conjugation of the EBNA1‐targeting peptides and porphyrins which can bring synergistic effects by both introducing more specific treatments (photodynamic therapy) and improving the biocompatibility of the photosensitizer and the peptides. One of our compounds exhibited significant photo‐cytotoxicity where the Lethal Concentration 50 (LC50)=6.1 μM in EBV‐positive cells. Besides, in vitro cell imaging and co‐staining can also be achieved simultaneously and suggested the binding inside nucleus. [ABSTRACT FROM AUTHOR]

An energy transition programme based on the principles of energy justice is an important way to mitigate climate change; however, empirical studies on energy justice remain scarce. This study explores key aspects of energy transition policy implementation in China, using three dimensions of energy justice – distributional, recognition and procedural justice – to establish an analytical framework and help develop quantification methodologies. We focused on Luquan District, Shijiazhuang City (Hebei Province, China), to assess energy justice levels following the implementation of China's 'coal-to-gas' energy transition policy in rural regions. The findings indicate that China's rural energy policy has not delivered energy justice. Analysis revealed a markedly low procedural justice index, registering a mere 0.37 on a scale of 0–1, attributable to factors such as the lack of involvement of rural households and a lack of transparency in the design and formulation of policy, as well as a lack of access of rural households to policy-related information. Furthermore, insufficient acknowledgment of the needs of specific groups during the energy transition has negatively impacted recognition justice, resulting in a mid-level index value of 0.69. By comparison, this study shows reveals a reasonably high energy distributional justice index value of 0.89. These findings suggest the need for the government to enhance energy policy communication and responsiveness to its stakeholders, to acknowledge and fairly address the energy transition needs of rural consumers, and to implement targeted energy subsidies to augment distributional justice and preclude the waste of limited financial resources. The analytical framework and calculation methods presented here could contribute to quantifying energy justice levels and to informing energy transition policy both in China and more broadly elsewhere in the world. Since 2013, implementation of China's 'coal-to-gas' energy transition policy has engendered impacts on different dimensions of social justice that have influenced the realization of a just transition. A composite index system is established, encompassing distributional justice, recognition justice, and procedural justice, and quantitative exploration of energy justice is undertaken using a reverse deduction method. The greatest losses in justice, following implementation of China's 'coal-to-gas' energy transition policy, are related to procedural justice, whereas recognition justice incurs moderate losses, and distributional justice experiences the lowest level of losses. Acknowledging the disparities among different groups, the ideal allocation of energy subsidies should be actualized through preliminary surveys, consultation and coordination, thereby preventing resource wastage. Recognizing individual rights and guaranteeing that the policy implementation process is open, transparent and participatory, could enhance energy justice and movement toward a just transition in the context of climate change policy. [ABSTRACT FROM AUTHOR]

Abstract This paper applied the modified Fourier series method to investigate the sound-vibration characteristics by establishing a composite laminated thin sector plate-cavity coupled model for the first time based on the classical plate theory (CPT) and Rayleigh-Ritz energy technique. The coupled system consists of an annular sector or circular sector plate backed by an acoustic cavity filled with air or water. Ignoring the influence of boundary conditions, displacements admissible functions of laminated sector plate and sound pressure admissible functions of cavity can be set up as a Fourier series superposition, whose composition are the superposition of Fourier cosine series and supplementary functions. The addition of these supplementary polynomials can effectively eliminate the discontinuity or jump phenomenon on the boundary. The correctness of the established analytical model has been validated by being compared with the results achieved by the finite element method (FEM). On this basis, the coupling mechanism of the weakly coupled system and the strongly coupled system are discussed in detail. In addition, some new results and discussions are given, including the cavity depth, plate thickness, anisotropic degree, varying boundary conditions and so on, which could provide reference for future research. [ABSTRACT FROM AUTHOR]

This paper presents a simple first-order shear deformation theory (SFSDT), which is used for the first time to analyze the vibro-acoustic characteristics of the laminated rectangular plate-cavity coupling system filled with air or water. The proposed theory contains only four unknowns and has greater application scope and higher computation accuracy compared with the classical plate theory (CPT). The admissible functions of displacements and sound pressure of the fluid-structure coupling system are expressed as superposition of the periodic functions based on the Fourier series method. Combined with the artificial virtual spring technology, the proposed theory could be used to analyze the composite coupling system under various combinations of classical boundary conditions or arbitrary elastic boundary conditions. Based on the free vibration analysis of the laminated rectangular plate in-vacuo, both the natural characteristics analysis and the forced response analysis under the excitation of a unit point force or a unit point sound source are carried out. The differences between the weak coupling system with air as medium and the strong coupling system with water as medium are discussed in detail and some new results and new conclusions have been given, which could be the benchmark for the future research. [ABSTRACT FROM AUTHOR]

This paper investigates the vibro-acoustic characteristics of the moderately thick laminated rectangular plate-cavity coupling system by using a modified Fourier series method. In the established model, two boundary conditions of moderately thick laminated rectangular plate are set as uniform elastic supports and non-uniform elastic supports including multi-points elastic supports or partial elastic supports. Besides, the three-dimensional rectangular cavity with rigid walls or impedance walls is discussed in the studied model. The admissible function of the displacements and sound pressure of the coupling system is set as the superposition function combined with Fourier cosine series and Fourier sin series. The Lagrangian energy principle is used to express the coupling system. The vibro-acoustic coupling characteristics can be obtained based on Rayleigh-Ritz technique. It shows good convergence and agreement of the present method by being compared with the finite element method (FEM) and the related literatures. This paper focuses on the study of free and forced vibro-acoustic analysis for the moderately thick laminated rectangular plate-cavity coupling system. Moreover, some results are achieved by discussing the effects of various plate thicknesses, different types of elastic supports, lamination schemes and various impedance boundary conditions on the natural characteristics and responses of the coupling system. [ABSTRACT FROM AUTHOR]

This paper establishes a plate-cavity system to study the vibro-acoustic coupling characteristics based on an improved Fourier series method (IFSM). The established coupling system consists of an acoustic cavity with rigid walls or impendence walls and a single or double thin laminated rectangular plate with various elastic boundary conditions. The energy principle is employed for the modeling of this coupling system. Under the framework, the displacement and sound pressure admissible functions are generally set, no relations to boundary conditions, to the combinations of Fourier cosine series and supplementary functions which can eliminate the discontinuous or jumping phenomenon in the boundaries. All the series expansion coefficients can be obtained through the Rayleigh-Ritz technique. The results obtained by presented method show good convergence and agreement by being compared with those of the literatures or finite element method (FEM). The natural characteristics of the plate-cavity coupling system are studied. The structure vibration response and acoustic pressure response are also investigated by applying structural force to the plate and applying the monopole source into the acoustic cavity. Furthermore, some new results are given, based on the various boundary conditions, anisotropic degrees, lamination schemes and cavity depths, which can be the benchmark for future research. [ABSTRACT FROM AUTHOR]

This paper focuses on the scientific problem of quantitative mineralization prediction at large depth in the Zaozigou gold deposit, west Qinling, China. Five geological and geochemical indicators are used to establish geological and geochemical quantitative prediction model. Machine learning and Deep learning algorithms are employed for 3D Mineral Prospectivity Mapping (MPM). Especially, the Student Teacher Ore-induced Anomaly Detection (STOAD) model is proposed based on the knowledge distillation (KD) idea combined with Deep Auto-encoder (DAE) network model. Compared to DAE, STOAD uses three outputs for anomaly detection and can make full use of information from multiple levels of data for greater overall robustness. The results show that the quantitative mineral resources prediction by applying the STOAD model has a good performance, where the value of Area Under Curve (AUC) is 0.97. Finally, three main mineral exploration targets are delineated for further investigation. [ABSTRACT FROM AUTHOR]

This paper focuses on researching the scientific problem of deep extraction and inference of favorable geological and geochemical information about mineralization at depth, based on which a deep mineral resources prediction model is established and machine learning approaches are used to carry out deep quantitative mineral resources prediction. The main contents include: (i) discussing the method of 3D geochemical anomaly extraction under the multi-fractal content-volume (C-V) models, extracting the 12 element anomalies and constructing a 3D geochemical anomaly data volume model for laying the data foundation for researching geochemical element distribution and association; (ii) extracting the element association characteristics of primary geochemical halos and inferring deep metallogenic factors based on compositional data analysis (CoDA), including quantitatively extracting the geochemical element associations corresponding to ore-bearing structures (Sb-Hg) based on a data-driven CoDA framework, quantitatively identifying the front halo element association (As-Sb-Hg), near-ore halo element association (Au-Ag-Cu-Pb-Zn) and tail halo element association (W-Mo-Co-Bi), which provide quantitative indicators for the primary haloes' structural analysis at depth; (iii) establishing a deep geological and geochemical mineral resources prediction model, which is constructed by five quantitative mineralization indicators as input variables: fracture buffer zone, element association (Sb-Hg) of ore-bearing structures, metallogenic element Au anomaly, near-ore halo element association Au-Ag-Cu-Pb-Zn and the ratio of front halo to tail halo (As-Sb-Hg)/(W-Mo-Bi); and (iv) three-dimensional MPM based on the maximum entropy model (MaxEnt) and Gaussian mixture model (GMM), and delineating exploration targets at depth. The results show that the C-V model can identify the geological element distribution and the CoDA method can extract geochemical element associations in 3D space reliably, and the machine learning methods of MaxEnt and GMM have high performance in 3D MPM. [ABSTRACT FROM AUTHOR]

Our previous studies demonstrated that tanshinone IIA (tan IIA) has significant protective effects against the neurotoxicity induced by β-amyloid protein (Aβ) in cultured cortical neurons and PC12 cells. This study was designed to investigate the protective effects of tan IIA against memory deficits induced by streptozotocin (STZ) in a model of sporadic Alzheimer’s disease (AD). STZ was injected twice intracerebroventrically (3 mg/kg ICV) on alternate days (day 1 and day 3) in mice. Daily treatment with tan IIA (20, 40, and 80 mg/kg, i.g.) starting from the first dose of STZ for 28 days showed a dose dependent improvement in STZ induced memory deficits as assessed by Morris water maze (MWM) test. Nissl staining results confirmed the protective effects of tan IIA on cerebral cortical and hippocampal neurons damage induced by STZ. In addition, tan IIA markedly reduced STZ induced elevation in acetylcholinesterase (AChE) activity and malondialdehyde (MDA) level, and significantly inhibited STZ induced reduction in superoxide dismutases (SOD) and glutathione peroxidase (GSH-Px) activities in the parietal cortex and hippocampus. Moreover, tan IIA attenuated p38 mitogen activated protein kinase (MAPK) phosphorylation in the parietal cortex and hippocampus. These findings demonstrate that tan IIA prevents STZ induced memory deficits may be attributed to ameliorating neuronal damage, restoring cholinergic function, attenuating oxidative stress and blocking p38 MAPK signal pathway activation. Based on our previous studies, the present study provides further support for the potential use of tan IIA in the treatment of AD. [ABSTRACT FROM AUTHOR]

The 5,10,15,20-tetrakis(1-methyl 4-pyridinio) porphyrins (TMPyP), a photosensitizer used for photodynamic therapy of cancers (PDT), were linked to carbon dots (CDots) to form the conjugates of CDot–TMPyP by the electrostatic force. The 415 nm emission band of CDots was well overlapped with the absorption band of TMPyP, so that the Cdots in conjugates can work as donor to transfer the energy to TMPyP moiety by fluorescence resonance energy transfer (FRET) with an FRET efficiency of 45%, determined by the fluorescence lifetime change between the free CDots and conjugated CDots. The two-photon absorption cross section (TPACS) of TMPyP is as low as 110 GM and the TMPyP thus be not suitable for two-photon PDT. Whereas the CDots have high TPACS, and their TPACS are excitation wavelength dependent with the maximum value of 15000 GM at 700 nm. Therefore, the conjugates of CDot–TMPyP were explored for two-photon excitation (TPE) PDT. The two-photon image of CDot–TMPyP in Hela cells was clearly seen under the excitation of a 700 nm femto-second (fs) laser. The singlet oxygen production of CDot–TMPyP was also much higher than that of TMPyP alone under TPE of a 700 nm fs laser. The in vitro PDT killing was further achieved with CDot–TMPyP by TPE of the 700 nm fs laser. Particularly herein the low power density of fs laser from unfocused laser beam was successfully used to carry out the TPE PDT, because of the high TPACS of CDots. These results demonstrate that the CDot–TMPyP conjugates are promising for TPE PDT and needed to investigate further. [ABSTRACT FROM AUTHOR]

A rapid and convenient detection method for biogenic polyamines is of great importance for early diagnosis of many diseases. In this work, a tetraphenyl ethylene (TPE) conjugated pentiptycene has been synthesized and showed to be a highly responsive fluorescent sensor toward polyamines. The detection limit of this probe is in the sub-micromolar level, and it also shows good selectivity for spermine. This small organic molecular bio-indicator can be used to detect spermine in artificial urine, demonstrating the potential application in clinical practice. • A TPE conjugated pentiptycene derivative SS-1 was synthesized and characterized. • The synergistic effects between the pentiptycene core and the TPE moiety was studied. • SS-1 selectively binds with spermine without interference from various amines and cations. • SS-1 can be applied for spermine detection in artificial urine solutions. [ABSTRACT FROM AUTHOR]

This paper proposes a structural-acoustic coupling model which is composed of an annular segment thin plate with various elastic boundary constraints and an acoustic enclosure with rigid-wall or various impedance-wall boundary conditions. The admissible displacement and sound pressure of the coupling system are written as superposition of simple periodic functions on the basis of an improved Fourier series method. The introduction of supplementary polynomials can effectively eliminate the discontinuous or jumping phenomenon in the boundaries. The coupling system is described by constructing energy formulation. Therefore, all the unknown series expansion coefficients can be solved by Rayleigh-Ritz energy technique. The fast convergence of the present method has been given by selecting smaller truncation values. In addition, the accuracy of the present method has been proved by being compared with the finite element method (FEM). The effect of various geometric parameters and boundary conditions on the vibro-acoustic characteristics of coupling system is investigated. Besides, the coupling responses are given by applying the point force on the annular segment plate or point sound source inside the enclosure. [ABSTRACT FROM AUTHOR]

Anaphylaxis is a rapid allergic reaction that may cause sudden death. Currently, postmortem diagnosis of anaphylactic shock is sometimes difficult and often achieved through exclusion. The aim of our study was to investigate whether Fourier transform infrared (FTIR) microspectroscopy combined with pattern recognition methods would be complementary to traditional methods and provide a more accurate postmortem diagnosis of fatal anaphylactic shock. First, the results of spectral peak area analysis showed that the pulmonary edema fluid of the fatal anaphylactic shock group was richer in protein components than the control group, which included mechanical asphyxia, brain injury, and acute cardiac death. Subsequently, principle component analysis (PCA) was performed and showed that the anaphylactic shock group contained more turn and α-helix protein structures as well as less tyrosine-rich proteins than the control group. Ultimately, a partial least-square discriminant analysis (PLS-DA) model combined with a variables selection method called the genetic algorithm (GA) was built and demonstrated good separation between these two groups. This pilot study demonstrates that FTIR microspectroscopy has the potential to be an effective aid for postmortem diagnosis of fatal anaphylactic shock. [ABSTRACT FROM AUTHOR]

Due to a lack of reliable and accurate methods, determining the postmortem interval (PMI) of human skeletal remains is one of the most important and challenging tasks in forensic medicine. In this paper, we studied the changes to bone chemistry with increasing PMI in two different experimental conditions using Fourier transform infrared (FTIR) spectroscopy in conjunction with chemometrics methods Paired bone samples collected from 56 human corpses were buried (placed in soil) and unburied (exposed to the air) for intervals between 76 and 552 days. The results of principle component analysis (PCA) showed the chemical differences of these two cases had a significant influence on the rate of decomposition of the remains. Meanwhile, satisfactory predictions were performed by the genetic algorithm combined with partial least-squares (GA-PLS) with the root mean square errors of prediction (RMSEP) of 50.93days for buried bones and 71.03days for unburied bones. Moreover, the amide I region of proteins and the area around 1390cm-1, which is associated with fatty acids, were identified with regular changes by GA-PLS and played an important role in estimating PMI. This study illustrates the feasibility of utilizing FTIR spectroscopy and chemometrics as an attractive alternative for estimating PMI of human remains and the great potential of these techniques in real forensic cases with natural conditions. [ABSTRACT FROM AUTHOR]

An improved Fourier series method (IFSM) is applied to study the free and forced vibration characteristics of the moderately thick laminated composite rectangular plates on the elastic Winkler or Pasternak foundations which have elastic uniform supports and multipoints supports. The formulation is based on the first-order shear deformation theory (FSDT) and combined with artificial virtual spring technology and the plate-foundation interaction by establishing the two-parameter foundation model. Under the framework of this paper, the displacement and rotation functions are expressed as a double Fourier cosine series and two supplementary functions which have no relations to boundary conditions. The Rayleigh-Ritz technique is applied to solve all the series expansion coefficients. The accuracy of the results obtained by the present method is validated by being compared with the results of literatures and Finite Element Method (FEM). In this paper, some results are obtained by analyzing the varying parameters, such as different boundary conditions, the number of layers and points, the spring stiffness parameters, and foundation parameters, which can provide a benchmark for the future research. [ABSTRACT FROM AUTHOR]

We report a direct imaging tool, HGEu001, for primary cilia in living cells, which is specific, and based on the UV light or near infrared laser (via two-photon excitation) induced long-lived europium luminescence. [ABSTRACT FROM AUTHOR]