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A novel fire-preventing triple-network (TN) hydrogel was prepared and laminated on cotton fabric to improve fire-resistant performance of cellulose fabric. The TN hydrogel composed of Poly (N-isopropylacrylamide) (PNIPAAm)/sodium alginate (SA)/ Poly (vinyl alcohol) (PVA) exhibited excellent swelling ratio, swelling-deswelling behavior and antibacterial property. Results indicated that introduction of SA could improve water retention capabilities of TN hydrogels. Thermogravimetric experiments showed that the thermal stability of hydrogels was best at a SA: PVA ratio of 2:1. Furthermore, the obtained hydrogel-cotton fabric laminates displayed efficient flame retardancy. Compared to original fabric, hydrogel-fabric laminates were nearly undamaged when exposed to fire for 12 s. This result is attributed to energy absorption as water is heated and evaporates in the hydrogel. The present work provides a new concept to prepare fire-resistant polymer fabric, which may be used in fire-protective clothing to protect the skin from burn injuries.

The efficacy of photodynamic therapy (PDT) in the solid tumor is hampered by many challenges, including its oxygen self-consuming nature, insufficient oxygen levels within the hypoxic tumor microenvironment, and limited penetration of photosensitizers within tumors. Herein, we develop the IR780@O2-SFNs/iRGD as an oxygen self-sufficient and tumor-penetrating nanoplatform, which consists of IR780-loaded pH-sensitive fluorocarbon-functionalized nanoparticles (SFNs) and iRGD as a tumor targeting peptide that can penetrate deeper within the tumor. Because of the high oxygen affinity and outstanding permeability of the obtained nanoplatform, oxygen and IR780 which are encapsulated in the same core can play their roles to the utmost, resulting in remarkably accelerated singlet oxygen production, as demonstrated in vitro by the 3D multicellular spheroids and in vivo by tumor tissues. More interestingly, a single-dose intravenous administration of IR780@O2-SFNs/iRGD into mice bearing orthotopic breast cancer could selectively accumulate at the tumor site, highly alleviate the tumor hypoxia, significantly inhibit the primary tumor growth, and reduce the lung and liver metastasis, enabling the improved photodynamic therapeutic performance. Thus, this work paves an effective way to improve PDT efficacy through increasing tumor oxygenation and selective delivery of photosensitizers to the deep and hypoxic tumor.

Although tremendous efforts have been made to construct gene vectors incorporating multiple functionalities and moieties, designing gene vectors integrating innovative features to successfully negotiate biological impediments, which hamper efficacious responses in gene-based therapy, is still very urgent. Herein, a light-induced virus-inspired mimic, in which a modular envelope was utilized to mask polyethylenimine/DNA (PD) polyplexes, was developed based on two pH-responsive polymers. The virus-inspired envelope, which was capable of achieving multitargeting and dual-pH-responsiveness in endo/lysosomal compartments, was composed of an internalizing arginylglycylaspartic acid-modified module and a citraconic anhydride-modified nuclear localized signal-functionalized module. The envelope conjugated with chlorin e6 (Ce6) was shielded on the surface of PD polyplexes. Dual-pH-responsive deshielding of the virus-inspired mimic in endo/lysosomes allowed generation of a nonfatal amount of reactive oxygen species (ROS) under short-time photoirradiation, leading to photochemical internalization and much more substantial enhancement in light-induced gene expression without DNA damage caused by ROS. Confocal images revealed that the virus-inspired mimic achieved successful nuclear translocation of Ce6, resulting in nucleus-targeting photodynamic therapy (PDT). Furthermore, pTRAIL-mediated gene therapy, accompanied by a fatal amount of ROS under long-time photoirradiation, additionally consolidated in vitro antitumor outcomes. This study demonstrates a novel paradigm of "one arrow, two hawks," accomplishing a combination of enhanced gene therapy and PDT.

In this study, Cu/Al composite castings were prepared using the pouring aluminum method, and the casting defects in the transition layer and their formation mechanism were investigated. Shrinkage cavities, shrinkage porosities, and cracks were easily formed in the transition layer, and the thickness of the transition layer was uneven after recombination of the solid Cu and liquid Al. Shrinkage cavities easily formed within the α + eutectic (α + CuAl2) phase, and cracks mainly appeared within the Cu9Al4 and CuAl2 phases. The transition layer with uneven thickness and irregular shape readily formed where the metals solidified last during the solidification; the difference in density between solid Cu and liquid Al, as well as the natural convection in the melt, were responsible for these irregular shapes. As the metals shrunk, shrinkage cavities and porosities formed without external melt feeding. Cracks formed in the Cu9Al4 and CuAl2 phases and at the Cu9Al4/CuAl2 and CuAl2/eutectic (α(Al + CuAl2) interfaces during the solid shrinkage process after the solidification was complete.

Multimodality optical imaging probes have emerged as powerful tools that improve detection sensitivity and accuracy, important in disease diagnosis and treatment. In this review, we focus on recent developments of optical fluorescence imaging (OFI) probe integration with other imaging modalities such as X-ray computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and photoacoustic imaging (PAI). The imaging technologies are briefly described in order to introduce the strengths and limitations of each techniques and the need for further multimodality optical imaging probe development. The emphasis of this account is placed on how design strategies are currently implemented to afford physicochemically and biologically compatible multimodality optical fluorescence imaging probes. We also present studies that overcame intrinsic disadvantages of each imaging technique by multimodality approach with improved detection sensitivity and accuracy., Graphical abstract This review is focused on the recent development of optical fluorescence imaging (OFI) probe integrating with imaging contrast agents. The multimodality fluorescence imaging probes are aimed to overcome intrinsic drawbacks of each imaging modality with complementary information from different modalities for improved sensitivity and accuracy, which are important in disease diagnosis and treatment.fx1

This research investigates pattern self-organization along the route to chaos in a space- and time-discrete predator–prey system, where the prey shows convection movement in space. Through analysis on Turing instability of the system, pattern self-organization conditions are determined. Based on the conditions, simulations are performed under two initial conditions, demonstrating two pattern transitions along the route to chaos. In the first pattern transition, the patterns start from regular stripes, experiencing twisted stripes, then return to regular stripes again. The second pattern transition is much more complex and shows three stages. Especially, an alternation between ordered patterns and disordered chaos is found, contributing greatly to the spatiotemporal complexity of the system. When the system stays at the homogeneous chaotic states, Turing instability driven by convection and diffusion can still force the self-organization of regular striped patterns. The finding in this research provides a new comprehending for pattern self-organization and transition in spatially extended predator–prey systems.

Hypochlorous acid (HOCl) is one of highly reactive oxygen species (ROS). It is involved in both immune defense against invading microbes and the progression of many diseases including cardiovascular disease and neurodegeneration disorders. It is generated from hydrogen peroxide (H 2 O 2 ) and chloride ions in the presence of myeloperoxidase in activated neutrophils. To illustrate HOCl’s biological functions, fluorescent probes, particularly those fluorescence emissions are in the near-infrared range, are highly needed for in vivo applications. Herein, we reported the design of a pinacol boronate caged near-infrared (NIR) fluorescent probe 1 derived from an A β binding fluorophore NIAD-4 for fast and selective detection of HOCl/ClO − over other ROS. Upon exposure to HOCl/ClO − , the pinacol boronate caging group of the probe 1 was quickly converted to electron-donating hydroxyl group, which increased intramolecular charge transfer (ICT) in the excited state and resulted in the red-shift and intensity enhancement of fluorescence emission. The probe bears several unique features: (1) It could be used as either a ratiomatic or turn-on fluorescent probe; (2) Reaction of the caging group boronate with HOCl is very fast and finishes within seconds, which provides the selectivity over H 2 O 2 ; (3) The NIAD-4 fluorophore provides additional selectivity for detection of HOCl over peroxynitrite. Moreover, the utility of the probe in imaging HOCl/ClO − was demonstrated in in vitro phantom imaging studies using mouse brain homogenate as biological relevant media.

This paper experimentally investigates the relationship between laser keyhole characteristics on the porosity formation during pulsed laser-GTA welding of magnesium alloy. Based on direct observations during welding process, the influences of laser keyhole state on the porosity formation were studied. Results show that the porosities in the joint are always at the bottom of fusion zone of the joint, which is closely related to the keyhole behavior. A large depth to wide ratio always leads to the increase of porosity generation chance. Keeping the keyhole outlet open for a longer time benefits the porosity restriction. Overlap of adjacent laser keyhole can effectively decrease the porosity generation, due to the cutting effect between adjacent laser keyholes. There are threshold overlap rate values for laser keyholes in different state.

A naphthalimide-aminal-based fluorescent donor (NAP-FAD-1) is a pH-sensitive smart donor, which features accelerated FA release at pH 5.0 compared to that at pH 7.4 and fluorescence turn-on readout for facile tracking and quantification of FA release. Confocal imaging studies of HeLa cells co-incubated with Lyso-Tracker Red suggested that its FA release is lysosome-targeted.

To provide a high-throughput, efficient, and accurate method to monitor multiple-fungicide resistance of

An integrated gene nanovector capable of overcoming complicated physiological barriers in one vector is desirable to circumvent the challenges imposed by the intricate tumor microenvironment. Herein, a nuclear localization signals (NLS)-decorated element and an iRGD-functionalized element based on O-carboxymethyl chitosan were synthesized, mixed, and coated onto PEI/DNA to fabricate bacterium-mimicking sequentially targeted therapeutic nanocomplexes (STNPs) which were internalized through receptor-mediated endocytosis and other pathways and achieved nuclear translocation of DNA. The endo/lysosomal membrane disruption triggered by reactive oxygen species (ROS) after short-time illumination, together with the DNA nuclear translocation, evoked an enhanced gene expression. Alternatively, the excessive ROS from long-time irradiation induced apoptosis in tumor cells, bringing about greater anti-tumor efficacy owing to the integration of gene and photodynamic therapy. Overall, these results demonstrated bacterium-mimicking STNPs could be a potential candidate for tumor treatments.

We reported a new approach to achieve enhanced selectivity with a drastic turn-on fluorescence response for the detection of Cys through dual intramolecular cyclization processes and dual PET and ICT quenching mechanisms by the incorporation of an acrylate and a maleimide group onto two opposite sides of a single coumarin fluorophore.

Pile-supported embankment is popularly used for constructing high-speed railways on soft soils. With train running at high speed, the dynamic load on the pile top generated by the train passages increases noticeably. To keep the long-term settlement of the railway track within a reasonable range, it is necessary to investigate the settlement of piles in soils simultaneously subject to the monotonic load caused by the weight of the track structure and embankment as well as the cyclic load caused by the train passages. In this paper, model tests on piles in silt soil under combined monotonic and cyclic loading were conducted. The behavior of a pile in saturated silt was investigated by measuring pile settlement, soil pressure on the pile surface, and pore water pressure in the soil adjacent to the pile. Based on the model testing results, the ratio of the mean value of cyclic load to the ultimate bearing capacity of the pile (Pm/Pu) and the ratio of the half amplitude of the cyclic load to the ultimate bearing capacity of the pile (Pcyc/Pu) were identified as the main factors dominating the development of pile settlement. A higher Pcyc/Pu leads to faster accumulation in the pile settlement, and a higher Pm/Pu facilitates this process. A chart with three zones determined by the combination of Pcyc/Pu and Pm/Pu has been proposed to distinguish the settlement trends of the piles: stable zone, metastable zone and unstable zone. The combination of Pcyc/Pu and Pm/Pu located in the stable zone generates very small settlement. Moreover, for the loading combination in the metastable zone, an analytical model was proposed to predict the cyclic pile settlement subject to cyclic load with large cycles. The advantage of the model is that the coefficient of friction at the pile surface and the cyclic strain degradation parameter are incorporated. Finally, a case study is presented to demonstrate the application of the proposed chart and the prediction method on cyclic pile settlement in the design of piled embankment of high-speed railways.

For safe and effective delivery of nucleic acid, a series of tunable membrane-penetrating nanogels were developed, which were constructed from reversibly cross-linked guanidinylated poly(L-lysine) dendrimers with various guanidination degrees and cross-linking degrees. The designed nanogels electrostatically interacted with DNA, resulting in condensed nanogelplexes with size of about 100 nm and positive zeta potential of 35 mV. Increased DNA complexing ability of nanogels can be achieved via increasing the guanidination degree. The presence of reductive agents gave rise to cleavage of disulfide bonds in PK3G30D2, in accompany with the collapse and swelling of nanogelplexes. Compared with PEI and PK3D2 lacking of guanidine groups, PK3G30D2 bearing 30 guanidine groups exhibited the highest transfection performance with good biocompatibility in serum-containing medium. Meanwhile, guanidination in collaboration with reversible cross-linking also promoted cellular internalization, lysosomal escape and release of DNA from condensed nanogelplexes, resulting in substantially improved transfection synergistically. The enhanced transfection efficiency by the guanidine-rich PK3G30D2 was also achieved in tibialis anterior muscles and tumor xenografts in mice. These results reveal these bioreductive and guanidinylated nanogels with synergistic effects might hold great potential for developing gene delivery system.

Smart polymers as ideal gene carriers have drawn increasing attentions due to the effective DNA release once triggered by intrinsic stimuli, as well as reduced cytotoxicity. Herein, a stimulus-responsive, positively charged and water-soluble polymer (OEI-TK

An important challenge for reaction-based fluorescent probes is that they generally require analyte consumption for fluorescence signal generation, thus creating potential perturbation of native analyte homeostasis or change of local concentrations. Herein, we reported two formaldehyde (FA) regeneration fluorescent probes, NAP-FAP-1 and NAP-FAP-2. An unprecedented regiospecific FA-induced intramolecularity strategy is implemented in the probe design, which adopts 3-(benzylamino)-succinimide as the FA-selective reaction group. The probes are able to capture the analyte molecule, induce regiospecific imide bond cleavage, and then release the captured FA molecule with simultaneous fluorescence turn-on response via a unique dual PeT/ICT quenching mechanism. The probes have shown potentials in detection, comparison, and imaging of FA levels intracellularly and inside lysosomes. These features make them useful for the study of FA homeostasis and functions in biological systems with minimal perturbation.

In the progress of designing a gene carrier system, what is urgently needed is a balance of excellent safety and satisfactory efficiency. Herein, a straightforward and versatile synthesis of a cationic guanidine-decorated dendronized pullulan (OGG3P) for efficient genetic photodynamic therapy was proposed. OGG3P was able to block the mobility of DNA from a weight ratio of 2. However, G3P lacking guanidine residues could not block DNA migration until at a weight ratio of 15, revealing guanidination could facilitate DNA condensation via specific guanidinium-phosphate interactions. A zeta potential plateau (∼+23 mV) of OGG3P complexes indicated the nonionic hydrophilic hydroxyl groups in pullulan might neutralize the excessive detrimental cationic charges. There was no obvious cytotoxicity and hemolysis, but also enhancement of transfection efficiency with regard to OGG3P in comparison with that of native G3P in Hela and HEK293T cells. More importantly, we found that the uptake efficiency in Hela cells between OGG3P and G3P complexes was not markedly different. However, guanidination caused changes in uptake pathway and led to macropinocytosis pathway, which may be a crucial reason for improved transfection efficiency. After introducing a therapeutic pKillerRed-mem plasmid, OGG3P complexes achieved significantly enhanced KillerRed protein expression and ROS production under irradiation. ROS-induced cancer cells proliferation suppression was also confirmed. This study highlights the guanidine-decorated dendronized pullulan could emerge as a reliable nonviral gene carrier to specifically deliver therapeutic genes.

Herein, a simple two-photon turn-on fluorescent probe, N-(6-acyl-2-naphthayl)-maleimide (1), based on a dual PeT/ICT quenching mechanism is reported for the highly sensitive and selective detection of cysteine (Cys) over other biothiols. The probe was applied in the two-photon imaging of Cys in cultured HeLa cells, excited by a near-infrared laser at 690 nm.

Complex dynamics of a four-species food web with two preys, one middle predator, and one top predator are investigated. Via the method of Jacobian matrix, the stability of coexisting equilibrium for all populations is determined. Based on this equilibrium, three bifurcations, i.e., Hopf bifurcation, Hopf-Hopf bifurcation, and period-doubling bifurcation, are analyzed by center manifold theorem, bifurcation theorem, and numerical simulations. We reveal that, influenced by the three bifurcations, the food web can exhibit very complex dynamical behaviors, including limit cycles, quasiperiodic behaviors, chaotic attractors, route to chaos, period-doubling cascade in orbits of period 2, 4, and 8 and period 3, 6, and 12, periodic windows, intermittent period, and chaos crisis. However, the complex dynamics may disappear with the extinction of one of the four populations, which may also lead to collapse of the food web. It suggests that the dynamical complexity and food web stability are determined by the food web structure and existing populations.

This research investigates the formation of banded vegetation patterns on hillslopes affected by interactions between sediment deposition and vegetation growth. The following two perspectives in the formation of these patterns are taken into consideration: (a) increased sediment deposition from plant interception, and (b) reduced plant biomass caused by sediment accumulation. A spatial model is proposed to describe how the interactions between sediment deposition and vegetation growth promote self-organization of banded vegetation patterns. Based on theoretical and numerical analyses of the proposed spatial model, vegetation bands can result from a Turing instability mechanism. The banded vegetation patterns obtained in this research resemble patterns reported in the literature. Moreover, measured by sediment dynamics, the variation of hillslope landform can be described. The model predicts how treads on hillslopes evolve with the banded patterns. Thus, we provide a quantitative interpretation for coevolution of vegetation patterns and landforms under effects of sediment redistribution.

Wind-induced vegetation patterns were proposed a long time ago but only recently a dynamic vegetation-sand relationship has been established. In this research, we transformed the continuous vegetation-sand model into a discrete model. Fixed points and stability analyses were then studied. Bifurcation analyses are done around the fixed point, including Neimark-Sacker and Turing bifurcation. Then we simulated the parameter space for both bifurcations. Based on the bifurcation conditions, simulations are carried out around the bifurcation point. Simulation results showed that Neimark-Sacker bifurcation and Turing bifurcation can induce the self-organization of complex vegetation patterns, among which labyrinth and striped patterns are the key results that can be presented by the continuous model. Under the coupled effects of the two bifurcations, simulation results show that vegetation patterns can also be self-organized, but vegetation type changed. The type of the patterns can be Turing type, Neimark-Sacker type, or some other special type. The difference may depend on the relative intensity of each bifurcation. The calculation of entropy may help understand the variance of pattern types.

The formation of self-organized patterns in predator-prey models has been a very hot topic recently. The dynamics of these models, bifurcations and pattern formations are so complex that studies are urgently needed. In this research, we transformed a continuous predator-prey model with Lesie-Gower functional response into a discrete model. Fixed points and stability analyses were studied. Around the stable fixed point, bifurcation analyses including: flip, Neimark-Sacker and Turing bifurcation were done and bifurcation conditions were obtained. Based on these bifurcation conditions, parameters values were selected to carry out numerical simulations on pattern formation. The simulation results showed that Neimark-Sacker bifurcation induced spots, spirals and transitional patterns from spots to spirals. Turing bifurcation induced labyrinth patterns and spirals coupled with mosaic patterns, while flip bifurcation induced many irregular complex patterns. Compared with former studies on continuous predator-prey model with Lesie-Gower functional response, our research on the discrete model demonstrated more complex dynamics and varieties of self-organized patterns.

Amphiphilic glycopolypeptide analogues have harboured great importance in the development of targeted drug delivery systems. In this study, lactosylated pullulan-graft-arginine dendrons (LP-g-G3P) was synthesized using Huisgen azide-alkyne 1,3-dipolar cycloaddition between lactosylated pullulan and generation 3 arginine dendrons bearing Pbf and Boc groups on the periphery. Hydrophilic lactosylated pullulan was selected for amphiphilic modification, aiming at specific lectin recognition. Macromolecular structure of LP-g-G3P combined alkyl, aromatic, and peptide dendritic hydrophobic moieties and was able to self-assemble spontaneously into core-shell nanoarchitectures with small particle sizes and low polydispersity in the aqueous media, which was confirmed by CAC, DLS and TEM. Furthermore, the polyaromatic anticancer drug (doxorubicin, DOX) was selectively encapsulated in the hydrophobic core through multiple interactions with the dendrons, including π-π interactions, hydrogen bonding and hydrophobic interactions. Such multiple interactions had the merits of enhanced drug loading capacity (16.89±2.41%), good stability against dilution, and excellent sustained release property. The cell viability assay presented that LP-g-G3P nanoparticles had an excellent biocompatibility both in the normal and tumor cells. Moreover, LP-g-G3P/DOX nanoparticles could be effectively internalized into the hepatoma carcinoma cells and dramatically inhibited cell proliferation. Thus, this approach paves the way to develop amphiphilic and biofunctional glycopolypeptide-based drug delivery systems.

The stability dilemma and limited tumor penetration of nanocarriers in cancer chemotherapy remain two predominant challenges for their successful clinical translation. Herein, the pH-sensitive fluorocarbon-functionalized nanocarriers (SFNs) with a tumor-homing and penetrating peptide iRGD are reported to overcome the stability dilemma and enhance tumor accumulation and penetration in an orthotopic breast cancer. The highly stable SFNs with a low critical association concentration provide a safe and spacious harbor for hydrophobic drugs. Furthermore, the stimulus-responsive evaluation and in vitro drug release study show that the SFNs can balance intracellular dissociation for drug release and extracellular stability in the blood circulation. Additionally, the tumor penetration capacity has been dramatically enhanced in 3D multicellular spheroids, effectively affecting cells far from the periphery. This can be ascribed to the coadministration of iRGD having tumor-penetrating ability and fluorocarbon chains having good cell membrane permeability. The combination of SFNs and iRGD is a viable approach to assist drugs' effective accumulation in primary and metastasized tumor sites, significantly inhibiting the breast tumor growth and curbing lung and liver metastases in an orthotopic-tumor-bearing mouse model. Taken together, this pH-sensitive fluorinated nanosystem having excellent stability and tumor accumulation and penetration properties paves the way to combat cancer.

Systemic gene delivery is a complicated and multistep process that confronts numerous biological barriers. It remains a formidable challenge to exploit a single gene carrier with multiple features to combat all obstacles collectively. Herein, a multi-responsive “turn-on” polyelectrolyte complex (DNA/OEI-SSx/HA-SS-COOH, DSS) delivery system is demonstrated with a sequential self-assembly of disulfide-conjugated oligoethylenimine (OEI-SSx) and disulfide bond-modified hyaluronic acid envelope (HA-SS-COOH) that can combat multiple biological barriers collectively when administered intravenously. DSS is designed to effectively accumulate at the tumor tissue and to be internalized into tumor cells by recognizing CD44. The multi-responsive “turn-on” DSS can respond to the alterations of hyaluronidases and glutathione at both the tumor site and at the intracellular milieu. Sequential degradation and detachment of the HA-SS-COOH envelope followed by the dissociation of the OEI-SSx/DNA inner core contributes to the activation of the endosomal escape and gene release functions, thus greatly enhancing nuclear gene delivery. A systematic investigation of DSS has revealed that the tumor accumulation ability, internalization, and endosome escape of the DSS nanocarriers, DNA unpacking and nuclear transportation are all remarkably improved by the multi-responsive “turn-on” design resulting in highly efficient gene transfection in vitro and in vivo.

PurposeHigh‐tech industry transferring shows different features to the transferring of the traditional industries. In order to explain those special features in China, the purpose of this paper is to build a new conceptual model for high‐tech industry transferring and explore some empirical evidence.Design/methodology/approachThis paper employs a perspective of specialization to analyze high‐tech industry transferring and a primary conceptual analytical model is discussed. Key models and methodologies are the industrial gravity center model, dynamic modes analysis, character induction and mechanism deduction method.FindingsThe features of high‐tech industry transferring within the China context include fast, surge, inverse‐gradient, as well as agglomeration and specification transferring. Based on the transfer pattern, high‐tech industry transferring modes are classified into two categories: vibration transferring and surge transferring.Originality/valueUsing a conceptual model, this paper analyzes the features of high‐tech industry transferring in China and proposes two typical patterns to explain how the industries transfer and what are the dynamic mechanisms. In order to improve high‐tech industry transferring in China, five policy implications are recommended.

In this study, the amphiphilic fluorinated peptide dendrons functionalized dextran (FPD-HZN-Dex) via an acid-sensitive hydrazone linkage was successfully designed and prepared for the first time. We demonstrated a spontaneous self-assembly of amphiphilic FPD-HZN-Dex into the well-defined nanoparticles with the core-shell architecture in aqueous media, which is attributed to the efficient amphiphilic functionalization of dextran by the hydrophobic fluorinated peptide dendrons. The spherical morphology, uniform particle size and good storage stability of the prepared FPD-HZN-Dex nanoparticles were characterized by dynamic light scattering and transmission electron microscopy, respectively. In vitro drug release studies showed a controlled and pH dependent hydrophobic drug release profile. The cell viability assays show excellent biocompatibility of the FPD-HZN-Dex nanoparticles for both normal cells and tumor cells. Moreover, the FPD-HZN-Dex self-assembled systems based on pH-sensitive hydrazone linkage also can serve as stimulus bioresponsive carriers for on-demand intracellular drug delivery. These self-assembled nanoparticles exhibit a stimulus-induced response to endo/lysosome pH (pH 5.0) that causes their disassembly over time, enabling controlled release of encapsulated DOX. This work has unveiled a unique non-covalent interaction useful for engineering amphiphilic dendrons or dendrimers self-assembled systems.

Ecological diversity refers to a combination of the richness and evenness of an investigation object. Based on this, the widely used model, Shannon model, and a recently developed model, Scaling ecological diversity model, were theoretically analyzed in this paper. It was indicated that Shannon model had many limitations, e. g., it could be available only when the number of each type of investigation object was more than 100, did not include any information of scale, and could not express the richness of diversity. In other words, Shannon model could only express the evenness of diversity. A case-study in Fukang of Xinjiang Uygur Autonomous Region showed that the richness and Shannon evenness were always resolution-dependent, while the ecotope diversity calculated by Scaling ecological diversity model was resolution-independent when the spatial resolution ranged from 30 m x 30 m to 150 m x 150 m, and strictly increased when the spatial resolution ranged from 150 m x 150 m to 480 m x 480 m.