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In this paper, we consider a class of focusing nonlinear Schrödinger equations involving power-type nonlinearity with critical Sobolev exponent { (i ∂ ∂ t + Δ) u + | u | 4 N − 2 s u = 0 , in R + × R N , u = u 0 (x) ∈ H 1 (R N) ∩ L 2 (R N , | x | 2 d x) , for t = 0 , x ∈ R N , where 2 N − 2 s = : p ⋆ be the critical Sobolev exponent with s < N 2. For dimension N ≥ 1 , the initial data u 0 belongs to the energy space and | ⋅ | u 0 ∈ L 2 (R N) and the power index s satisfies [ 0 , 1 ] ∋ s ≡ s c = N 2 − 1 p ⋆ , we prove that the problem is non-global existence in H 1 (R N) (here, finite-time blow-up occurs) with the energy of initial data E [ u 0 ] is negative. Moreover, we establish the stability for the solutions with the lower bound and the global a priori upper bound in dimension N ≥ 2 related conservation laws. The motivation for this paper is inspired by the mass critical case with s = 0 of the celebrated result of B. Dodson [9] and the work of R. Killip and M. Visan [18] represented with energy critical case for s = 1. Our new results mention to nonlinear Schrödinger equation for interpolating between mass critical or mass super-critical (s ≥ 0) and energy sub-critical or energy critical (s ≤ 1). [ABSTRACT FROM AUTHOR]

In this paper, we study the dynamics behavior of the (NLS system) with three waves interaction in the energy space H 1 (R 5) × H 1 (R 5) × H 1 (R 5) . Inspired by Dodson and Murphy (Math Res Lett 25(6):1805–1825, 2018), we establish an interaction Morawetz estimate for the (NLS system), together with the criterion which proved by Tao–Dodson–Murphy we can get the scattering under the ground state in energy space with mass-resonance. Under the radial assumption, we can remove the mass-resonance condition. [ABSTRACT FROM AUTHOR]

We revisit the scattering result below the ground state of Y. Gao and H. Wu [Scattering for the focusing H ˙ 1 2 -critical Hartree equation in energy space. Nonlinear Anal. 2010;73:1043–1056] on the radial focusing energy-subcritical Hartree equation in d = 5, using the method in Dodson and Murphy [A new proof of scattering below the ground state for the 3D radial focusing cubic NLS. preprint, arXiv:1712.09962]. Using the radial Sobolev embedding and a virial-Morawetz type estimate we can exclude the concentration of mass near the origin instead of using the concentration compactness method in Gao and Wu [Scattering for the focusing H ˙ 1 2 -critical Hartree equation in energy space. Nonlinear Anal. 2010;73:1043–1056]. [ABSTRACT FROM AUTHOR]

Agonists of the cyclic guanosine monophosphate–adenosine monophosphate synthase (cGAS)-Stimulator of Interferon Genes (STING) pathway, a critical mediator of innate immune response to foreign invaders with DNA, have gained significant interest in cancer immunotherapy. STING agonists are envisioned as a way of complementing the antitumor activity of the patient's immune system and immune checkpoint blockade therapy. However, their clinical development has been challenging due to the poor pharmacokinetic and physicochemical properties. This review discusses drug delivery efforts to circumvent the challenges, their accomplishment, and unmet needs based on the last five years of literature. • STING agonists can enhance cancer immunotherapy. • STING agonists have unfavorable pharmacokinetic and physicochemical properties. • Particles, hydrogels, cells, and antibodies are used to improve STING agonist delivery. [ABSTRACT FROM AUTHOR]

The stability of the surrounding rock in the goaf is one of the main factors to ensure the safety of the mining production. In this study, a coupled numerical simulation model of particle flow code, computational fluid dynamics, and parallel-bounded stress corrosion (PFC-CFD-PSC model) was proposed to conduct the seepage-creep coupling simulation through PFC 5.0 software. Based on the mechanical results, the crack propagation law of the coal measure sandstone under the mining-induced seepage-creep coupling load was analyzed, and the distribution of pressure gradient in the fluid grid was studied. The results show that seepage pressure has a significant effect on the damage of the rock mass; the greater the seepage pressure on the coal measure sandstone model, the more penetration cracks are generated and the greater the degree of macroscopic damage. When the residual strength is 70% of the peak strength, the damage degree of the coal measure sandstone increases with the increase of the seepage pressure; except for the four corners, the pressure gradient of the fluid at the top of the rock mass model is relatively large. The maximum value of the fluid grid pressure gradient increases with the increasing seepage pressure; it increases slowly under the seepage pressure of less than 1.5 MPa and increases sharply under the seepage pressure of greater than 1.5 MPa. [ABSTRACT FROM AUTHOR]

A group of nucleic acids and oligonucleotides play various roles in the innate immune system. They can stimulate pattern recognition receptors to activate innate immune cells, encode immunostimulatory proteins or peptides, or silence specific genes to block negative regulators of immune cells. Given the limitations of current cancer immunotherapy, there has been increasing interest in harnessing innate immune responses by nucleic acids and oligonucleotides. The poor biopharmaceutical properties of nucleic acids and oligonucleotides make it critical to use carriers that can protect them in circulation, retain them in the tumor microenvironment, and bring them to intracellular targets. Therefore, various gene carriers have been repurposed to deliver nucleic acids and oligonucleotides for cancer immunotherapy and improve their safety and activity. Here, we review recent studies that employed carriers to enhance the functions of nucleic acids and oligonucleotides and overall immune responses to cancer, and discuss remaining challenges and future opportunities in the development of nucleic acid-based immunotherapeutics. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Emerging mite-borne pathogens and associated disease burdens in recent decades are raising serious public health concerns, yet their distributions and ecology remain under-investigated. We aim to describe the geographical distributions of blood-sucking mites and mite-borne agents and to assess their ecological niches in China. Methods: We mapped 549 species of blood-sucking mites belonging to 100 genera at the county level and eight mite-associated agents detected from 36 species of blood-sucking mites in China during 1978–2020. Impacts of climatic and environmental factors on the ecology of 21 predominant vector mites and a leading pathogen, Orientia tsutsugamushi, were assessed using boosted regression tree (BRT) models, and model-predicted risks were mapped. We also estimated the model-predicted number, area and population size of affected counties for each of the 21 mite species in China. Results: Laelaps echidninus is the leading mite species that potentially affects 744 million people, followed by La. jettmari (517 million) and Eulaelaps stabularis (452 million). Leptotrombidium scutellare is the mite species harboring the highest variety of mite-borne agents including four Rickettsia species and two viruses, followed by Eu. stabularis (2 agents), L. palpale (2) and La. echidninus (2). The top two agents that parasitize the largest number of mite species are O. tsutsugamushi (28 species) and hantavirus (8). Mammalian richness, annual mean temperature and precipitation of the driest quarter jointly determine the ecology of the mites, forming four clusters of major mite species with distinct geographic distributions. High-risk areas of O. tsutsugamushi are mainly distributed in southern and eastern coastal provinces where 71.5 million people live. Conclusions: Ecological niches of major mite species and mite-borne pathogens are much more extensive than what have been observed, necessitating expansion of current filed surveillance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 2D-COF (CuABD) realizes efficient charge transfer within the framework. • The HCOOH production rate over CuABD can reach 1.26 mmol g−1 h−1. • The π-conjugated skeleton propelled electronic delocalization and carrier transport. Sunlight-driven CO 2 reduction to value-added chemicals is an effective strategy to promote carbon recycling. The exploration of catalysts with efficient charge separation is crucially important for highly efficient CO 2 photoreduction. In this work, the preparation of metal-cluster-based covalent organic framework (CuABD) integrated features from both metal organic frameworks (MOFs) and covalent organic frameworks (COFs) through the condensation of diamines and functionalized trinuclear copper clusters demonstrate a thoughtful design strategy. The reported yield of 1.3 mmol g−1 h−1 for formic acid (HCOOH) under simulated solar irradiation is impressive, surpassing the performance of many COF- and MOF-based catalysts previously reported. Compared to its isomorphic metal-free structure (named BDFTD) and bare trinuclear Cu cluster which present extremely poor catalytic activities, CuABD displays remarkably enhanced CO 2 reduction activity. Experimental and theoretical investigations reveal that the efficient charge transfer between diamine monomer and cyclic trinuclear copper (I) units, and the electron delocalization of the π-conjugated framework are responsible for the appealing catalytic performance. In summary, the work presents a well-structured and scientifically sound exploration of a metal-cluster-based covalent organic framework for efficient CO 2 reduction under sunlight. [ABSTRACT FROM AUTHOR]

In this paper, we simplify the proof of M. Hamano in [13] , scattering theory of the solution to (NLS system) , by using the method from B. Dodson and J. Murphy in [10]. Firstly, we establish a criterion to ensure the solution scatters in H 1 (R 5) × H 1 (R 5). In order to verify the correctness of the condition in scattering criterion, we must exclude the concentration of mass near the origin. The interaction Morawetz estimate and Galilean transform characterize a decay estimate, which implies that the mass of the system cannot be concentrated. [ABSTRACT FROM AUTHOR]

In this manuscript, ultrastable Y (USY) zeolites are modified employing a liquid‐phase ion exchange method to furnish H‐USY with different properties. Modified with ammonium nitrate, H‐USY could largely improve the conversion in the alkylation reaction of benzene with cyclohexene due to the increase in Brunauer‐Emmett‐Teller (BET) specific surface area, Barrett‐Joyner‐Halenda (BJH) pore volume, BJH pore size, and acidity of H‐USY. Catalyzed by the molecular sieve modified twice with ammonium nitrate, this alkylation reaction demonstrated a 95.3 % conversion of cyclohexene with 97.4 % selectivity of cyclohexylbenzene. And we found that urea‐modified USY has the similar effect, a 96.1 % conversion of cyclohexene with slightly 94.9 % selectivity of cyclohexylbenzene. [ABSTRACT FROM AUTHOR]

Abstract A metal–dielectric waveguide (MDW) structure was presented to generate surface electromagnetic waves (SEWs) suitable for short wavelength (<500 nm) working in aqueous environment. Aluminum thin film was employed to adapt for the short wavelength and silica layer was introduced to form the low loss surface mode, whose energy is mainly confined at silica/water interface. Transfer matrix theory was used to investigate theoretically the above ideas, and the process to design and optimize the structural parameters of the MDW structure for the SEWs was also introduced. Experiments were performed to validate the existence and the low loss nature of the SEWs, and the wavelength of the excited SEW was measurement by a home-built near field scanning system which accords well with the theoretical prediction. This type of SEWs on a MDW structure can be as an alternative to overcome the limitations associated with the traditional metal-type waveguide mode such as surface plasmon polariton, and could be potential for applications like the imaging, bio-sensing, precision measurement, etc. [ABSTRACT FROM AUTHOR]

Many nanoparticle matrixes have been demonstrated to be efficient in brain targeting, but there are still certain limitations for them. To overcome the shortcomings of the existing nanoparticulate systems for brain-targeted delivery, a lipoprotein resembling protein-free nanostructured lipid carrier (PS80-NLC) loaded with curcumin was constructed and assessed for in vitro and in vivo performance. Firstly, single factor at a time approach was employed to investigate the effects of various formulation factors. Mean particle sizes of ≤100 nm, high entrapment efficiency (EE, about 95%) and drug loading (DL, >3%) were obtained for the optimized formulations. In vitro release studies in the presence of plasma indicated stability of the formulation under physiological condition. Compared with NLC, PS80-NLC showed noticeably higher affinity for bEnd.3 cells (1.56 folds greater than NLC) but with lower uptake in macrophages. The brain coronal sections showed strong and widely distributed fluorescence intensity of PS80-NLC than that of NLC in the cortex. Ex vivo imaging studies further confirmed that PS80-NLC could effectively permeate BBB and preferentially accumulate in the brain (2.38 times greater than NLC). The considerable in vitro and in vivo performance of the safe and biocompatible PS80–NLC makes it a suitable option for further investigations in brain targeted drug delivery. [ABSTRACT FROM AUTHOR]

In this study, a novel low density lipoprotein (LDL)-mimic nanostructured lipid carrier (NLC) modified with lactoferrin (Lf) and loaded with curcumin (Cur) was designed for brain-targeted delivery, and its effect on controlling the progression of Alzheimer's disease (AD) in rats was evaluated. NLC with the composition resembling the lipid portion of LDL was prepared by using solvent evaporation method. Lf was adsorbed onto the surface of NLC via electrostatic interaction to yield Lf modified-NLC (Lf-mNLC) as the LDL-mimic nanocarrier. In order to make sure more Lf was adsorbed on the surface of NLC, negatively charged carboxylated polyethylene glycol (100) monostearate (S100-COOH) was synthesized and anchored into NLC. Different levels of S100-COOH (0–0.02 mmol) and Lf modified NLC (0.5–2.5 mg/mL of Lf solution) were prepared and characterized. The uptake and potential cytotoxicities of different preparations were investigated in the brain capillary endothelial cells (BCECs). An AD model of rats was employed to evaluate the therapeutic effects of Lf-mNLC. The results indicate that Lf-mNLC with a high level of Lf showed the maximum uptake in BCECs (1.39 folds greater than NLC) as cellular uptake of Lf-mNLC by BCECs was found to be mediated by the Lf receptor. FRET studies showed Cur still wrapped inside NLC after uptake by BCECs, demonstrating stability of the carrier as it moved across the BBB. Ex vivo imaging studies exposed Lf-mNLC could effectively permeate BBB and preferentially accumulate in the brain (2.78 times greater than NLC). Histopathological evaluation confirmed superior efficacy of Lf-mNLC in controlling the damage associated with AD. In conclusion, Lf-mNLC is a promising drug delivery system for targeting therapy of brain disease. [ABSTRACT FROM AUTHOR]

• The 5-substituted groups of the aryl in sulfonylureas have a key impact on inhibition bioactivity against fungi. • 5-substituted sulfonylureas have much better inhibitory activities against fungi than those of Fluconazole (FCZ) and amphotericin B (AMB). • An unusual possible double-pocket binding model in the active site of C. albicans AHAS catalytic subunit is revealed. • The low energy gap value between the HOMOs and LUMOs contributes to maintenance or improvement of the inhibition bioactivity against fungi microbes. Acetohydroxyacid synthase (AHAS; EC2.2.1.6) exists solely in plants and microbes, and the biosynthesis of branched chain amino acids (valine, leucine and isoleucine) gets obstructed when sulfonylureas bind to AHAS catalytic subunit active site, which leads to the inability to synthesize these proteins and eventually causes the death of plants and microbes. Thus, the AHAS is also a promising antifungal target. Nowadays, there is an urgent need to discover new potential targets and chemical structures to prevent the growing morbidity and mortality of fungal infections and the emergence of severe antifungal drug resistance. In this work, 36 target compounds were designed and synthesized and several 5-substituted sulfonylureas possess much better antifungal activities than those of Fluconazole (FCZ) and amphotericin B (AMB). The most potent of these were L10, L23 and L31 with inhibition constants (K i) determined in the range of 5.6∼9.6 nM for C. albicans AHAS and MICs(The MIC was determined as the drug concentration that inhibits fungal growth by >90% relative to the corresponding drug-free growth control) <0.05∼0.78 µg/mL for C. albicans SC 5314, 17# and 2# (17# and 2# are two clinically isolated FCZ-resistant strains of C. albicans), S. cerevisiae SCXH1549 and C. parapsilosis ATCC22019 in YNB (yeast nitrogen base) media at 72 h post-treatment. Using the same media, the commercial MICs of FCZ and AMB were only determined in the range of 0.25∼5 µg/mL for the five strains at 24 h post-treatment. In order to elaborate the structure-activity relationship (SAR) a proposed double-pocket binding mode was simulated via molecular docking. The energy gap between the HOMOs and LUMOs of selected compounds showed that the 5-substituted groups of sulfonylureas have key impact on the antimicrobial bioactivity. [Display omitted] [ABSTRACT FROM AUTHOR]

We study the focusing nonlinear Schrödinger equation with inverse-square potential i ∂ t u + Δ u − a | x | 2 u + | u | p − 1 u = 0 with a > − 1 4 and 3 4 < p − 1 < 4 in three dimensions. In this paper we obtain blow-up and global existence criteria for the solution to ( N L S a ) by the method from Duyckaerts-Roudenko [1], which extend a recent work of Killip-Murphy-Visan-Zheng [2] to above the threshold. [ABSTRACT FROM AUTHOR]

We study the focusing inhomogeneous nonlinear Schrödinger equation with inverse‐square potential i∂tu+Δu−a|x|2u+|x|−b|u|2u=0,$$ i{\partial}_tu&amp;#x0002B;\Delta u-\frac{a}{{\left&amp;#x0007C;x\right&amp;#x0007C;}&amp;#x0005E;2}u&amp;#x0002B;{\left&amp;#x0007C;x\right&amp;#x0007C;}&amp;#x0005E;{-b}{\left&amp;#x0007C;u\right&amp;#x0007C;}&amp;#x0005E;2u&amp;#x0003D;0, $$where a>−14$$ a&gt;-\frac{1}{4} $$ and 0

Mechanochemical has emerged as an eco-friendly, efficient, and upscalable tool for the synthesis of perovskite quantum dots (PQDs). However, achieving control over the size and ensuring good mono-dispersion of PQDs by mechanochemistry, while simultaneously increasing their stability remains a great challenge. Herein, we specifically chose a lead bromine-based MOF (PbBr-MOF) with [Pb 2 Br 3 ]+ nodes and utilized the uniform distribution of [Pb 2 Br 3 ]+ to induce the in-situ confined growth of Cs 4 PbBr 6 QDs via bottom-up mechanochemical approach for the first time, denoted as Cs 4 PbBr 6 @PbBr-MOF. The Cs 4 PbBr 6 QDs uniform and firmly anchor in PbBr-MOF through [Pb 2 Br 3 ]+ nodes, preventing their aggregation and enhancing quantum confinement effects. Highly dispersed Cs 4 PbBr 6 QDs (3.86 ± 0.61 nm) exhibit high photoluminescence quantum yield (31%) and notable durability in various solvents. Furthermore, Cs 4 PbBr 6 @PbBr-MOF demonstrates excellent performance as a temperature sensor, with maximum absolute (Sa) and relative (Sr) temperature sensitivities of up to 0.013 K−1 and 3.41% K−1, respectively. [Display omitted] • [Pb 2 Br 3 ]+ nodes in PbBr-MOF as Cs 4 PbBr 6 QDs precursors. • Enhancing Cs 4 PbBr 6 's confinement effect through controlled CsBr and nodes dispersion. • Cs 4 PbBr 6 QDs have 3.86 ± 0.61 nm size with high photoluminescence yield (31%). • PbBr-MOF boosts Cs 4 PbBr 6 QDs stability in harsh conditions. • Cs 4 PbBr 6 @PbBr-MOF shows impressive temp sensitivity. [ABSTRACT FROM AUTHOR]

Polyethyleneimine (PEI) is widely used for the delivery of nucleic acids, but its clinical application is limited due to high cytotoxicity and instability in biological fluids. To overcome these challenges, linear PEI (2.5 kDa) was modified with lithocholic acid (LCA) to produce a LCA-PEI conjugate (lp), and its complex with plasmid DNA (pDNA) was covered with hyaluronic acid (HA). Ternary complexes of pDNA, lp, and HA ("DlpH") were prepared in different ratios and tested in cells and tumor-bearing mice for gene transfection efficiency. DlpH with a relatively high lp/pDNA ratio (Hi-DlpH) was more resistant to DNase and heparin treatment and showed more efficient gene transfection than DlpH with a lower lp/pDNA ratio (Lo-DlpH) in vitro. In contrast, Hi- and Lo-DlpH showed distinct transfection efficiency in vivo in a tumor-size dependent manner, where Hi-DlpH showed relatively high gene transfection in tumors of <300 mm3 but performed poorly in tumors of >500 mm3 and Lo-DlpH did the opposite. Tumor-associated macrophages, which increase with tumor growth and preferentially intercept Hi-DlpH, may account for the poor performance of Hi-DlpH in relatively large tumors. Accordingly, suggestions are made for future in vitro screening of new gene formulations to better predict their in vivo performances. Image 1 [ABSTRACT FROM AUTHOR]

Background: Activation of VDR pathway was a promising anti-tumor therapy strategy. However, numerous clinical studies have demonstrated the effect of activating VDR is limited, which indicates that VDR plays a complex role in vivos. Methods: We analyzed the TCGA database to examine the association between VDR expression and immune cell infiltration in pancreatic adenocarcinoma (PAAD). Western blot, ELISA, ChIP, and dual-luciferase reporter assays were performed to determine the mechanism of VDR regulating CCL20. Migration assay and immunofluorescence were used to investigate the role of CCL20 in M2 macrophage polarization and recruitment. We employed multiplexed immunohistochemical staining and mouse models to validate the correlation of VDR on macrophages infiltration in PAAD. Flow cytometry analysis of M2/M1 ratio in subcutaneous graft tumors. Results: VDR is extensively expressed in PAAD, and patients with elevated VDR levels exhibited a significantly reduced overall survival. VDR expression in PAAD tissues was associated with increased M2 macrophages infiltration. PAAD cells overexpressing VDR promote macrophages polarization towards M2 phenotype and recruitment in vitro and vivo. Mechanistically, VDR binds to the CCL20 promoter and up-regulates its transcription. The effects of polarization and recruitment on macrophages can be rescued by blocking CCL20. Finally, the relationship between VDR and M2 macrophages infiltration was evaluated using clinical cohort and subcutaneous graft tumors. A positive correlation was demonstrated between VDR/CCL20/CD163 in PAAD tissues and mouse models. Conclusion: High expression of VDR in PAAD promotes M2 macrophage polarization and recruitment through the secretion of CCL20, which activates tumor progression. This finding suggests that the combination of anti-macrophage therapy may improve the efficacy of VDR activation therapy in PAAD. [ABSTRACT FROM AUTHOR]

Halide perovskite nanocrystals are innovative luminescent materials for fluorescent probes with high quantum yield and narrow emission bandwidth. However, the limited stability, single-signal response, and separation challenges obstruct their widespread use in water ion detection. Herein, a ratiometric fluorescence sensor based on terbium alginate gel beads (green fluorescent, namely Tb-AG) embedded with powdered CsPbI3@Pb-MOF (red fluorescent) was prepared for fluorescent determination and adsorption of Fe3+. Pb-MOF's protection notably enhances the water stability of CsPbI3, while the energy transfer between CsPbI3@Pb-MOF and Tb3+ elevates the optical performance of CsPbI3@Pb-MOF@Tb-AG. Significantly, Fe3+ markedly suppresses CsPbI3@Pb-MOF red fluorescence at 647 nm, while not noticeably affecting Tb-AG green emission at 528 nm. The sensor exhibited a strong linear response to Fe3+ concentrations ranging from 0 to 90 μM, with a detection limit of 0.44 μM and high selectivity. The CsPbI3@Pb-MOF@Tb-AG-based sensor has been effectively validated through its successful use in detecting Fe3+ in tap and river water samples. Furthermore, CsPbI3@Pb-MOF@Tb-AG demonstrates a notable adsorption capacity of 325.4 mg g−1 Fe3+. Finally, the mechanism of Fe3+ detection and adsorption was determined. [ABSTRACT FROM AUTHOR]

Strongly confined electromagnetic (EM) fields generated by tightly focused light beams are applied widely in nano‐optics due to their vectorial characteristics. The inclusion of the longitudinal polarized component plays a crucial role in both the physical characteristics and practical uses of tightly focused vector beams. The acquisition of the distributions of the three orthogonal polarized components of these fields is advantageous for the comprehensive examination of their captivating physical phenomena and possible applications. However, this continues to pose a noteworthy obstacle, especially in the case of the fields that are generated by high numerical aperture objectives. A novel approach is proposed to quantifying the three mutually perpendicular polarizations simultaneously in the focal plane. The method utilizes a dual‐mode waveguide probe that is composed of a dielectric nanoparticle and a metal‐dielectric waveguide. This design allows for the simultaneous support of both transverse electric (TE) and transverse magnetic (TM) modes. Consequently, it enables the polarization recognition of scattering light in k‐space. Importantly, this method effectively eliminates any interference originating from the background light. The work involves an analysis of the theoretical notion of the probe and followed by experimental investigations. This approach holds promise for augmenting optical nanoscopy methodologies and their associated applications. [ABSTRACT FROM AUTHOR]

In this paper, we consider the scattering theory of the radial solution to focusing energy‐subcritical Hartree equation with inverse‐square potential in the energy space H1(Rd) using the method from [4]. The main difficulties are due to the fact that the equation is not space‐translation invariant and that the nonlinearity is non‐local. Using the radial Sobolev embedding and a virial‐Morawetz type estimate we can exclude the concentration of mass near the origin. Besides, we can overcome the weak dispersive estimate when a<0, using the dispersive estimate established by [23]. [ABSTRACT FROM AUTHOR]

Photonic spin skyrmions with deep‐subwavelength features have aroused considerable interest in recent years. However, the manipulation of spin structure in the skyrmions in a desired manner is still a challenge, while this is crucial for developing the skyrmion‐based applications. Here, an approach of optical spin manipulation by utilizing the spin‐momentum equation is proposed to investigate the spin texture in a photonic skyrmion‐pair. With the benefit of the proposed approach, a unique spin texture with spin angular momentum varying linearly along the line connecting the two skyrmion centers is theoretically designed and experimentally verified. The optimized spin texture is then applied in a displacement‐sensing system, which is capable of attaining pico‐metric sensitivity. Compared with the conventional polarization and phase schemes, the spin‐based manipulation mechanism provides a new pathway for optical modulation, which is of great value in nanophotonics from both fundamental and application. [ABSTRACT FROM AUTHOR]

Poly(lactide- co -glycolide) (PLGA) polymers have been widely used for drug delivery due to their biodegradability and biocompatibility. One of the objectives of encapsulating a drug in PLGA microparticles (MPs) is to achieve an extended supply of the drug through sustained release, which can range from weeks to months. Focusing on the applications needing a relatively short-term delivery, we investigated formulation strategies to achieve a drug release from PLGA MPs for two weeks, using meloxicam as a model compound. PLGA MPs produced by the traditional oil/water (O/W) single emulsion method showed only an initial burst release with minimal increase in later-phase drug release. Alternatively, encapsulating meloxicam as solid helped reduce the initial burst release. The inclusion of magnesium hydroxide [Mg(OH) 2 ] enhanced later-phase drug release by neutralizing the developing acidity that limited the drug dissolution. The variation of solid meloxicam and Mg(OH) 2 quantities allowed for flexible control of meloxicam release, yielding MPs with distinct in vitro release kinetics. When subcutaneously injected into rats, the MPs with relatively slow in vitro drug release kinetics showed in vivo drug absorption profiles consistent with in vitro trend. However, the MPs that rapidly released meloxicam showed an attenuated in vivo absorption, suggesting premature precipitation of fast-released meloxicam. In summary, this study demonstrated the feasibility of controlling drug release from the PLGA MPs over weeks based on the physical state of the encapsulated drug and the inclusion of Mg(OH) 2 to neutralize the microenvironmental pH of the MPs. [Display omitted] • Meloxicam was encapsulated in PLGA microparticles for sustained release over 2 weeks. • Encapsulation of meloxicam in the solid state reduced the initial burst release. • Inclusion of Mg(OH) 2 enhanced drug release in the later phase. • Microparticles showed a consistent trend in in vivo drug absorption as in vitro results when the release was relatively slow. [ABSTRACT FROM AUTHOR]

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening immune disorder categorized as familial HLH or secondary HLH. Our case report describes a 63-year-old woman with epilepsy whose clinical signs were unremitting fever and altered consciousness. Primary abnormalities consisted of fever, splenomegaly, cytopenia, hypertriglyceridemia, hyperferritinemia and hemophagocytosis in the bone marrow. Results of blood next generation sequencing and blood culture confirmed Brucella infection. This report illustrates a sHLH case caused by Brucella melitensis infection. Here, we review the classification, clinical features, diagnostic methods, treatment regimens, differential diagnosis, and prognosis of HLH and brucellosis. [ABSTRACT FROM AUTHOR]

Since the seminal work by J. H. Poynting, light has been known to carry momentum and angular momentum. The typical dynamical features of light and its interactions—termed spin–orbit interactions (SOIs), which have been investigated intensely over the last 30 years—play a crucial role in various light-matter interactions, for example: spin Hall effect, spin–orbit conversion, helicity-controlled unidirectional excitation of light, and their inverse effects, which leads to plenty of applications including optical manipulation, communications, imaging, sensing, nanometrology, on-chip optoelectronic technologies and interdisciplinary researches. In particular, the SOI of light in isotropic inhomogeneous media is a fine, subwavelength effect accomplished through the intrinsic coupling between light's phase, polarization and position. Therefore, the traditional methods of near-field measurements, such as near field scanning optical microscopy (NSOM), have been widely employed to reveal the optical SOIs intuitively by measuring the intensity of light. Very recently, with modern advanced nanofabrication techniques, many measurement techniques based on nanoparticles, nanoantennas, and nanoprobes of special designs have been proposed to understand the optical SOIs visually by characterizing the polarization and spin/orbital features of light. This endeavor has led to the development of chiral quantum optics, spin optics, and topological photonics, and resulted in novel applications requiring optical manipulations and angular momentum communications, chiral imaging, nanometrology, and robust spin-based devices and techniques for quantum technologies. Here, we review the near-field techniques for measurements of optical SOIs together with their potential applications. We start with a theoretical overview of momentum and angular momentum properties of generic optical fields and typical phenomena involving optical SOIs. Then, we overview the theoretical basis and latest achievements of the near-field measurement techniques, including NSOM, optical manipulations, nanoantenna, and nanoprobes of special designs, all relevant to optical SOIs. A comprehensive classification is then constructed of all known methods of optical near-field measurements for the SOI of light and novel techniques identified for future applications. [ABSTRACT FROM AUTHOR]

Cutting force is the key signal to realize intelligent control of shearer and mastering the change process of cutting force is helpful to improve the adaptive cutting of shearer. In this paper, full scale rock cutting tests are used to carry out single pick cutting experiments on three kinds of coal, and the acoustic emission (AE) signals of coal and rock cutting are monitored in the whole process. The relationship between AE and cutting force is also discussed. The results show that the development of AE energy can represent the different stages of the cutting process, and the time fractal dimension of AE energy can reveal the change law of coal structure stability. In addition, the acoustic emission waveform at the peak cutting force of the same kind of coal has the same main frequency, power spectrum density (PSD) variation law, and the area under PSD curve; for different types of coal, the area under PSD curve at peak cutting force increases with the increase of USC. In the cutting process, the AE signal has obvious characteristics and internal evolution law in energy amplitude, fractal dimension, and PSD index. The change characteristics of AE energy can be used as the precursor information of the peak cutting force, and the coal failure at the peak cutting force has the identity. The above conclusions are of great significance for intelligent control of shearer and intelligent mining of coal mine. [ABSTRACT FROM AUTHOR]

The stability of a deep composite roof is a powerful guarantee for the safe and efficient production of a coal mine. The coal–rock combination, the single rock or coal bodies have different bearing capacity; thus, we can accurately obtain the deformation field evolution and failure mechanisms of the combination, which is useful in the deformation control of a composite roof. In this study, based on the digital speckle correlation method (DSCM), a uniaxial compression test was applied to coal–rock combinations with different height ratios. The results revealed that the compressive strength, elastic modulus, and secant modulus of the combination gradually decreased, while the decreasing amplitude weakened with the increase of coal height. Additionally, the strain field map of the combination had different characteristics in different stages. As the height of the coal body continuously increased, the gradient of the strain cloud and the area of local strain increase moved upwards. Moreover, the cracks caused by the failure of the coal body in the combination triggered the failure of the rock body. According to the test results, two principles are proposed for the deformation control of the composite roof, and are expected to be useful in applications for the similar geological conditions. [ABSTRACT FROM AUTHOR]

To ensure safe mining of the 3153 working face in the Chengzhuang mine, with its thin aquifuge, we developed a complete set of methods, including transient electromagnetics, drilling, a water injection experiment, and a numerical simulation based on a new constitutive model. Thus, the groundwater distribution, the aquifuge thickness, and the floor damage thickness were obtained successively and the results from each method could be mutually verified. The main results were: (1) The floor damage thickness decreases when the backfill affects the floor, and further thickens as the hanging roof area increases. (2) Under cyclic loading, tension and compression damage zones are connected. The deepest compression damage lags the coal wall, while the point of maximum tensile damage lags the deepest compression damage zone, thus forming an inclined water-conductive zone. [ABSTRACT FROM AUTHOR]

Gap mode surface-enhanced Raman spectroscopy (SERS) enables high enhancement of Raman signal. However, the polarization of excitation light shows great influence on the excitation of gap mode and hence on the Raman enhancement. Here, we propose a nanoparticle-on-film gap mode SERS accompanying with a new type of excitation source called as perfect radially polarized (PRP) beam. The PRP beam possesses a ring-shaped beam pattern that can be tuned to match the surface plasmon resonance angle under a tight focusing condition, hence improving greatly the excitation efficiency of surface plasmon polaritons, and eventually the sensitivity of gap mode SERS. Such kind of enhanced-Raman system with a PRP beam has a great potential on the applications such as single molecule Raman detection. [ABSTRACT FROM AUTHOR]

A novel coumarin-based fluorescence probe has been constructed for the selective and sensitive detection of hydrogen sulfide (H2S). This probe displays high sensitivity and linearity to H2S in degassed PBS buffers and fetal bovine serum. It reacts with H2S with high selectivity over Cys, GSH, and other anions. Meanwhile, successful detection of H2S in living cells was also demonstrated. [ABSTRACT FROM AUTHOR]

We report crosslinker free self assembly of bovine serum albumin (BSA) and a hydrophobic payload paclitaxel (PTX), into nanoparticles by harnessing the temperature driven unfolding of protein. To systematically study the effects of various factors responsible for the key attributes of the nanoparticles, a Resolution IV design was used. 20 formulations were made with pH, temperature, time of heating before and after addition of drug, stirring rate, protein concentration, and protein to drug ratio selected as independent variables. Particle size, encapsulation efficiency, yield and zeta potential were the response variables. Perturbation and Pareto charts were used to single out the important factors, while, mathematical equations and 3D surface charts have been used to describe the relationship between dependent and independent variables. Nanoparticles with size of 188–482 nm were observed with a highly negative zeta potential of −39.5 to −21.9. Nanoparticles obtained had decent encapsulation efficiency (72.5–87.9%) with effective yield (80.0–93.8%). Validation of the mathematical models with 4 runs indicated the good prognostic ability of Resolution IV design. Spectroscopic studies suggested the non-covalent complexation between BSA and PTX as the possible mechanism of self assembly due to irreversible conformational changes in protein. Transmission Electron Microscopy (TEM) revealed spherical nanoparticles with a porous network of PTX–BSA. X-ray Diffraction (XRD) showed amorphous nature of nanoparticles. PTX release from the nanoparticles was found to be controlled release and followed Peppas–Sahlin model. In vitro cytotoxicity of PTX–BSA nanoparticles was comparable to that of Taxol after 48 h treatment. These findings suggest heat driven BSA self assembly as a viable approach to formulate cytotoxic drug carrying nanoparticles which could be efficiently used in anti-cancer therapy. [ABSTRACT FROM AUTHOR]

Bacterial pathogens residing in host macrophages in intracellular infections are hard to eradicate because traditional antibiotics do not readily enter the cells or get eliminated via efflux pumps. To overcome this challenge, we developed a new particle formulation with a size amenable to selective macrophage uptake, loaded with two antibacterial agents - pexiganan and silver (Ag) nanoparticles. Here, pexiganan was loaded in 600 nm poly(lactic-co-glycolic acid) (PLGA) particles (NP), and the particle surface was modified with an iron-tannic acid supramolecular complex (pTA) that help attach Ag nanoparticles. PLGA particles coated with Ag (NP-pTA-Ag) were taken up by macrophages, but not by non-phagocytic cells, such as fibroblasts, reducing non-specific toxicity associated with Ag nanoparticles. NP-pTA-Ag loaded with pexiganan (Pex@NP-pTA-Ag) showed more potent antibacterial activity against various intracellular pathogens than NP-pTA-Ag or Pex@NP (pexiganan-loaded NP with no Ag), suggesting a collaborative function between pexiganan and Ag nanoparticles. Mouse whole-body imaging demonstrated that, upon intravenous injection, NP-pTA-Ag quickly accumulated in the liver and spleen, where intracellular bacteria tend to reside. These results support that Pex@NP-pTA-Ag is a promising strategy for the treatment of intracellular bacterial infection. [ABSTRACT FROM AUTHOR]

The catalytic dehydrogenation of propane to propene is an alternative technique to supplement the traditional steam cracking and catalytic cracking process for satisfying the continuously increasing demand for propylene downstream products. In this study, the parent PtSn/γ-Al2O3 catalyst was fabricated via the one-step method for the subsequent La post-modification to prepare the catalysts for propane dehydrogenation. The prepared and spent catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, scanning electron microscope (SEM), NH3 temperature-programmed desorption (NH3-TPD), H2 temperature-programmed desorption (H2-TPR), and thermogravimetric (TG) analysis. The catalytic performance and characterization results demonstrated that the addition of La into the parent catalyst could significantly improve the catalytic performance of the prepared catalyst. Especially, the PtSn-La2.2 catalyst with the 2.2 wt.% La addition exhibited the stable and highest propylene selectivity (>84%) under the investigation time of 800 min. The introduced La exhibits the ability to adjust the textural properties of the obtained catalysts, curb the acidity of support, promote the reduction of Pt species, and reduce the carbon accumulation on the prepared catalysts. [ABSTRACT FROM AUTHOR]

Background: Wide use of ciprofloxacin and levofloxacin has often led to increased resistance. The resistance rate to these two agents varies in different clinical isolates of Enterobacteriaceae. Mutations of GyrA within the quinolone resistance-determining regions have been found to be the main mechanism for quinolone resistance in Enterobacteriaceae. It has been shown that only some of the mutations in the gyrA gene identified from clinical sources were involved in fluoroquinolone resistance. Whether different patterns of gyrA mutation are related to antimicrobial resistance against ciprofloxacin and levofloxacin is unclear.Methods: The minimum inhibitory concentration (MIC) of ciprofloxacin and levofloxacin were determined by the agar dilution method followed by PCR amplification and sequencing of the quinolone resistance determining region of gyrA to identify all the mutation types. The correlation between fluoroquinolone resistance and the individual mutation type was analyzed.Results: Resistance differences between ciprofloxacin and levofloxacin were found in 327 isolates of K. pneumoniae and E. coli in Harbin, China and in the isolates reported in PubMed publications. GyrA mutations were found in both susceptible and resistant isolates. For the isolates with QRDR mutations, the resistance rates to ciprofloxacin and levofloxacin were also statistically different. Among the 14 patterns of alterations, two single mutations (Ser83Tyr and Ser83Ile), and three double mutations (Ser83Leu+Asp87Asn, Ser83Leu+Asp87Tyr and Ser83Phe+Asp87Asn) were associated with both ciprofloxacin and levofloxacin resistance. Two single mutations (Ser83Phe and Ser83Leu) were related with ciprofloxacin resistance but not to levofloxacin. Resistance difference between ciprofloxacin and levofloxacin in isolates harboring mutation Ser83Leu+Asp87Asn were of statistical significance among all Enterobacteriaceae (P<0.001).Conclusions: Resistance rate to ciprofloxacin and levofloxacin were statistically different among clinical isolates of Enterobacteriaceae harboring GyrA mutations. Ser83Leu+Asp87Asn may account for the antimicrobial resistance difference between ciprofloxacin and levofloxacin. [ABSTRACT FROM AUTHOR]