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The systemic toxicity and low efficacy of traditional chemotherapy for hepatocellular carcinoma (HCC) result in poor clinical outcomes. This study was designed to achieve targeted delivery of apoptin plasmid (AP) to liver tumors and killing of cancer cells using multifunctional nanoparticles (MFNPs) having sustained-release properties. The MFNPs featuring a distinct core-shell structure were prepared using poly(lactic-glycolic acid)-ε-polylysine copolymer and loaded with AP by adsorption. Specific targeting of liver tumor cells was achieved by biotinylation of the nanoparticles (NPs), while an improvement in lysosomal escape and nuclear localization enhanced the tumor cell killing capability of AP. Blank MFNPs exhibited good biocompatibility while AP-loaded NPs were found to exert strong inhibitory effects on both tumor cells in vitro and solid tumors in vivo. Taken together, these findings demonstrate a promising route for the development of tumor-targeted NPs which may lead to improved therapeutic strategies for treating HCC.

Background The detrimental impact of psychological birth trauma is far-reaching for women. This study aimed to identify the relationship between social support, childbirth readiness, and psychological birth trauma and to further explore whether childbirth readiness can play a mediating role. Methods A nationwide online cross-sectional study was conducted among 751 primiparous women in seven provinces in China from November 2021 to March 2022. The questionnaire consisted of questions on demographic characteristics, the Psychological Birth Trauma Scale (PBTS), the Chinese Mandarin version of the Medical Outcomes Study Social Support Survey (MOS-SSS-CM), and the Childbirth Readiness Scale (CRS). Hierarchical multiple regression was used to explore the associate factors and mediating role of childbirth readiness in the relationship between social support and psychological birth trauma. The mediating model was examined by the PROCESS macro for SPSS. Results After adjusting for demographic variables, social support was negatively associated with psychological birth trauma (r=-0.242, Pr = 0.206, Pr=-0.351, P

The transport behaviors of proton into nanoporous materials were investigated using different Monte Carlo simulation codes such as GEANT4, Deeper and SRIM. The results indicated that porous structure could enhance the proton scattering effects due to a higher specific surface area and more boundaries. The existence of voids can deepen and widen the proton distribution in the targets due to relatively lower apparent density. Thus, the incident protons would transport deeper and form a wider Bragg peak in the end of the range, as the target materials are in a higher porosity state and/or have a larger pore size. The existence of voids also causes the local inhomogeneity of proton/energy distribution in micro/nano scales. As compared, the commonly used SRIM code can only be used to estimate roughly the incident proton range in nanoporous materials, based on a homogeneous apparent density equivalence rule. Moreover, the estimated errors of the proton range tend to increase with the porosity. The Deeper code (designed for evaluation of radiation effects of nuclear materials) can be used to simulate the transport behaviors of protons or heavy ions in a real porous material with porosity smaller than 52.3% due to its modeling difficulty, while the GEANT4 code has shown advantages in that it is suitable and has been proven to simulate proton transportation in nanoporous materials with porosity in its full range of 0~100%. The GEANT4 simulation results are proved consistent with the experimental data, implying compatibility to deal with ion transportation into homogeneously nanoporous materials.

Temperature is one of the physical parameters that affects the emission luminescence properties of upconversion (UC) materials. Temperature-dependent emission color tuning and good temperature sensitivity in multifunctional β-NaYF4:Yb/Er@β-NaYF4:Yb/Tm microcrystals were achieved under 980 nm excitation. Based on the different emission bands (blue, green and red bands) and spectral sensitivities of the core–shell structured microcrystals to temperature, intense white-light emission was obtained at room temperature and a real-time naked-eye recognizable emission color change from white to the purplish-pink region was realized with the temperature increasing from 300 to 500 K. Furthermore, optical temperature sensing properties of the sample with good sensitivity (from 0.0034 to 0.0044 K−1) were investigated by using a fluorescence intensity ratio between 521 nm (2H11/2 → 4I15/2 transition) and 540 nm (4S3/2 → 4I15/2 transition) in the temperature range from 300 to 500 K. The results indicate that the sample has high sensitivity in a relatively wide range of temperature intervals, especially in the low temperature region. We believe that the multifunctional core–shell structured microcrystals exhibit promising applications in white-light emitting diodes, the anti-counterfeiting field, and temperature sensing.

An ultrafast route at room temperature has been developed for the first time to synthesize lanthanide ion (Yb3+/Er3+)-activated K0.3Bi0.7F2.4 fluorescent nanoparticles and hold the potential to be applied in luminescent temperature sensors. In addition, the crystal structure and morphology of the K0.3Bi0.7F2.4 nanoparticles prepared at different reaction conditions were studied in detail for the first time, including the reaction time and different mole ratios of Bi source and NH4F. Moreover, Yb3+/Er3+ doped in the K0.3Bi0.7F2.4 matrix using a luminescent thermometer based on the fluorescence intensity ratio technology was also investigated. Additionally, K0.3Bi0.7F2.4:Yb3+/Er3+ revealed excellent up-conversion luminescence performance, and the up-conversion mechanisms of samples are affirmed according to the up-conversion emission intensity as a function of the pump power density. Simultaneously, the optical thermometric performance of the samples was investigated in the temperature range of 323–523 K to indagate the temperature sensor performance. Significantly, the maximum sensor sensitivity of the studied nanoparticles were 0.0058 K−1 (Sa) at 523 K and 1.08 K−1 (Sr) at 323 K, which indicates that K0.3Bi0.7F2.4:20%Yb3+/2%Er3+ fluorescent nanoparticles can be exploited as a promising luminescent thermometer.

Intense white-light color emission of lanthanide-doped core-shell structured particles at microscale level was presented under 980 nm excitation. The prepared NaYF4:Yb/Er@ NaYF4:Yb/Tm microcrystals not only can effectively prevent the deleterious cross-relaxation that occurs between the Er3+ and Tm3+ due to the location of the activator ions within different layers, but also possess a high luminescence efficiency due to dimensions of the micro-scale structure. The core-shell structured microcrystals presented satisfactory capacity for color control in the white region. The results show great potential in attaining white light-emitting diodes within the field emission display on specific device applications. Furthermore, the core-shell microcrystals emit white-light that presents obvious and distinct lifetimes of green, red, and blue emissions, which could achieve multicolor emissions by setting a suitable delay time. This feature demonstrates that the core-shell structured microrods offer practical use as security ink to prevent forgery, such as in identifying currency.

The carbon-dots/NaLuF4 microcrystals have been synthesized by the hydrothermal method and bright blue emission from carbon dots is observed in aqueous and solid state under 365 nm excitation. Self-quenching property of the carbon-dots/NaLuF4 microcrystals under solid state was deeply investigated, by changing the ratio of citric acid (CA) and ethylenediamine (DHE). The results indicate that the carbon dots can be effectively adsorbed and dispersed on the surface of NaLuF4 microcrystals, suppressing the aggregation of carbon dots. Furthermore, the upconversion luminescence can also be realized under 980 nm laser excitation. From the above observations, the carbon-dots/NaLuF4 microcrystals not only reveal emission property of carbon dots and NaLuF4, respectively, but also optimize the property of carbon dots. It provides a promising new strategy to prevent the carbon dots quenching in solid state and the carbon-dots/NaLuF4 microcrystals may have potential multi-applications in different fields including temperature sensing, solid-state display lighting as well as security inks.

Dynamic tuning upconversion color is the most convenient approach through modulation of pump power density and NIR wavelength for anti-counterfeiting. However, most of bulk upconversion systems suffer from the insensitive response to excitation power and NIR wavelength (980 nm and 1550 nm). Herein, we demonstrate that the excitation power density sensitivity and NIR wavelength sensitivity of bulk microcrystals could be improved via co-doping Li+/Lu3+ ions. More interestingly, co-doping ions with different valences affect the emission color tendency at 1550 nm excitation, which is contrary to previous reports. The emission color of bulk NaYF4:Er/Yb/Li/Lu microcrystals transform from yellow to bright green color through adjusting pump power density and pump wavelength (980 nm and 1550 nm). Moreover, the mechanism of the results has been systematically discussed. The tunable emission colors of bulk NaYF4:Er/Yb/Li/Lu microcrystals can be easily distinguished with naked eyes and difficultly counterfeited. Therefore, the upconversion materials have a promising application in transparent anti-fake printing.

4Pi stimulated emission depletion (STED) microscopy shows outstanding three-dimensional (3D) isotropic super-resolution imaging performance. However, this technology is still difficult for achieving long-term studying of the synapses that are deeply embedded inside brain tissue. Metalens, which can realize arbitrary nanoscale amplitude, phase, and polarization modulations, is a very useful tool to solve this limitation. In this paper, an ultracompact two-photon 4Pi STED microscopy involved two multifunctional metalenses patterned on the two fiber facets respectively for focusing the excitation and depletion laser beams to the same position was proposed to realize the 3D isotropic super-resolution imaging. The designed complementary structure of two metalenses and the optimized pupil ratio β assured the symmetry of the STED spot. Furthermore, the isotropic super-resolution of 27 nm was theoretically implemented based on the two-photon STED theoretical model. Our approach will greatly increase the viability of the 3D super-resolution morphological imaging in the deep brain.

Simultaneous monitoring multiple drug delivery with different drug ratios can obtain the real-time relationship between drug ratios and therapeutic effects, which can accelerate the composite drugs development for some uncertain epidemics. We introduce a method of constructing flexible inorganic core-shell nanofibers with tunable multicolor upconversion fluorescence to satisfy the demand of simultaneous monitoring. The tunable green to red ratio varying from 5 to 0.3 is obtained by proposed pretreatment followed by reoxidation process, which need not to change chemical constituents or concentrations thereby would not bring about disadvantageous fibrous morphology and bad spinnability. Compared with traditional method that cannot monitor dual drug delivery and show a low sensitivity, the nanofibers prepared by our new method exhibit a high sensitivity verified by simultaneously monitoring dual drug delivery with multiple different drug ratios. Due to the tunable green to red ratio and appropriate selection criteria, these nanofibers exhibit a broad detection range of two drugs without losing excellent sensitivity, which cannot be achieved by conventional single-drug monitoring system.

Trivalent lanthanide ion (Ln3+) doped UC materials can emit visible light under near-infrared (NIR) excitation due to anti-stokes shift and have received wide attention. In this paper, we presented a new strategy to synthesize the uniform and smooth microstructures (rodlike and tubular) based on hexagonal phase NaYF4 microcrystals. Moreover, we systematically discussed the method of enhancing the upconversion (UC) luminescence intensity via co-doping the ions with different valences (Li+ and Lu3+) in order to tailor the environment around lanthanide ions. The UC intensities in the two microstructures were significantly improved. The results suggested the great application potential of tubes and rods of β-NaYF4 microcrystals in anti-counterfeiting, laser media, photonic crystals, and waveguides.

The NaGdTiO4:Yb3+/Tm3+ phosphor has been effectively synthesized by the traditional solid-state reaction method and its down-conversion and up-conversion luminescence properties were systematically studied. The results indicate that the electric dipole-dipole interaction is the main mechanism for the luminescence quenching. The fact that the ratios of the up-conversion intensities, i.e., I795nm/I798nm, I807nm/I798nm, and I812nm/I798nm, increase linearly with temperature (100 K–300 K) provides us a simple and accurate temperature measurement method. Multi-ratios can be more accurate than using only one ratio, allowing for self-referenced temperature determination. It's promising for NaGdTiO4: Yb3+/Tm3+ to be used for optical temperature sensors.

Poly( l -lactic acid) (PLLA) sheets with dramatic improvement of mechanical properties, especially toughness, were obtained by uniaxial pre-stretching around Tg. It was found that a network structure consisting of cohesional entanglements was formed during the usual compression molding process, leading to the brittleness of PLLA, and the destruction of the network structure due to disentanglement after pre-stretching, leading to the toughness of PLLA. The network structure could not be destroyed when pre-stretching ratio (PSR) was in the elastic deformation region I and strain softening region II (PSR

Color-tunable upconversion emission was explored in the NaGdTiO4 synthesized by a high temperature solid-state reaction process. NaGdTiO4:Er3+, NaGdTiO4:Yb3+/Tm3+ and NaGdTiO4:Yb3+/Er3+ are mainly dominated by green, blue and yellow light emissions under 980 nm diode laser, respectively. The intensity ratios of red to green luminescence and blue to green luminescence increase with increasing the concentration of Yb3+ in NaGdTiO4:Yb3+/Tm3+/Er3+ phosphors. Changing the power of laser can influence the photon transfer pathways and eventually tune the emission colors. Additionally, the laser excitation heating effect and the temperature dependent spectra were also investigated, which indicated that the laser-induced heating effect was not the main reason for the laser power to change the emission. The CIE chromaticity coordinates of NaGdTiO4:60%Yb3+/1%Tm3+/5%Er3+ are close to the standard white light (x = 0.33, y = 0.33) and the sample has a good thermal stability. The strategies for color tuning of upconversion emission proposed in the NaGdTiO4 would be beneficial to achieve efficient multicolor (including white light) luminescence.

β-NaLuF4:Yb3+/Er3+ microcrystals have been obtained through a facile hydrothermal method at a relatively low temperature (180 °C) within only two hours. By introducing Ca2+ ions, the microcrystals can simultaneously be tunable in size and realize upconversion luminescence enhancement. It is found that when the concentration of Ca2+ ions increases from 0 to 20 mol%, the average diameter of disks increases while the height decreases. However, with the concentration of Ca2+ further increasing, the opposite is true. This result can be ascribed to the capping effect of F− on the different crystal faces. More importantly, the upconversion luminescence intensities of green and red emissions of β-NaLuF4:Yb3+/Er3+ with 40 mol% Ca2+ ion doping are about 7.5 and 7.9 times higher than those of the sample without Ca2+ doping, respectively. Besides, the Ca2+ doping can also be extended to β-NaLuF4:Er3+/Tm3+ for enhancement of the upconversion luminescence. Eventually, emphasis will be on the temperature-dependent upconversion properties of β-NaLuF4:20Yb3+/2Er3+/40Ca2+ (mol%) and Ca2+-free samples. The maximum sensitivity of β-NaLuF4:20Yb3+/2Er3+/40Ca2+ (mol%) (0.00040 K−1) is higher than that of β-NaLuF4:20Yb3+/2Er3+ (mol%) (0.00021 K−1) at 120 K under the same excitation pump power of 1 W, indicating that the sample with Ca2+ has potential for application to temperature sensing.

Thermally conductive poly (3-hydroxylbutyrate) (PHB)/poly (ethylene oxide) (PEO)/boron nitride (BN) composites were fabricated by powder mixing. The thermal conductivity of PHB composite was remarkably enhanced by incorporating a small amount of PEO. SEM images revealed that segregated and co-continuous structures were formed in PHB composites. Owing to the addition of PEO, acting as a binder, BN particles were able to stack more closely and covered larger size of PHB aggregates than PHB/BN composites did. In addition, the partial miscibility between PHB and PEO could efficiently improve the interaction between BN particles and PHB matrix. Besides, during the hot pressing process, PEO could penetrate into the voids existing between BN particles and lead the phonon scattering to decrease. The hydrogen bonding existed between PEO and BN particles also played an important role to the thermal conductivity enhancement of PHB composites. These factors combined were believed to result in higher thermal conductivity of PHB/PEO/BN composites than PHB/BN composites fabricated by powder mixing.

PHB/BN/Al2O3 composites with high thermal conductivity were fabricated in melt blending process. A synergistic effect in the thermal conductivity enhancement of PHB composites was achieved. DSC results indicate that the crystallinity of PHB slightly changes and the XRD results show that the crystal forms of PHB remain unchanged. Additionally, the rheological properties indicate that thermally conductive fillers have formed thermally conductive pathways in PHB in the low frequencies. However, the viscosity of PHB composites remarkably decreases after the introduction of Al2O3 which facilitates the processibility of the PHB composites. Consequently, it can be suggested that more efficient thermally conductive pathways, originates from the alignment of BN on the Al2O3 surfaces, are formed due to the lower viscosity which leads to a decreased thermal interface resistance along the BN/Al2O3 hybrid filler network. This synergistic effect provides a method to acquire a polymer composite with higher thermal conductivity, but with lower viscosity.

Thulium, terbium, and manganese tridoped phosphate glass ceramic was prepared by high-temperature melting method and heat annealing technology. The sample can emit strong white light under 355 nm excitation. The luminescence intensities and peak positions keep unchanged in the temperature range of 25-300°C. The phosphate glass ceramic material shows good property of thermal stability, which can be exploited for the phosphor of white-light-emitting diode.

Poly(butylene adipate-co-terephthalate) (PBAT) and thermoplastic starch (TPS) were blended by using maleic anhydride (MA) as a compatibilizer. Preferentially, TPS could be reacted with MA to obtain maleated thermoplastic starch (MTPS). Then PBAT/MTPS blends were blown films using blown technique. From dynamic mechanical analysis, the shifting of the glass transition temperatures toward each other suggested that PBAT was partially miscible with MTPS. From wide angle X-ray diffraction analysis, the degree of crystallinity of PBAT/MTPS films was decreased with increasing MTPS content. From rheological measurements, the melt elasticity and viscosity of the PBAT/MTPS blends increased. It was benefit to extrude blend and blow film. The contact angle values of bipolar liquid water were range from 100.2 to 77.7 ° decreased with increasing MTPS content from 0 to 50 %. The PBAT/MTPS films could satisfy the requirement for applying in our life.

This work aims at studying optical properties of Eu3+ dopant in K0·3Bi0·7F2.4 host and seeking their applications. A series of orange red emitting K0·3Bi0·7F2.4:Eu3+ phosphors were synthesized via a chemical precipitation reaction method at room temperature, which is convenient, economical and less time consuming. XRD and Rietveld refinement results confirm the pure phase of as-prepared materials. The optimal doping concentrations are determined to be 40%mmol, and both of the corresponding concentration quenching mechanism have been validated to be dipole−dipole interactions. Additionally, the Judd-Ofelt theory was selected to study the local structure environment of the Eu3+ ions in the K0·3Bi0·7F2.4 host lattices and the tendency of J-O parameters (Ω2>Ω4) confirm the asymmetric environment around Eu3+ ions. The thermogravimetric analysis and activation energy results of K0·3Bi0·7F2.4:Eu3+ materials with high thermal stability exhibit promising performances for temperature sensor applications. Moreover, the temperature-dependent of samples are investigated in a large temperature range of 303–573 K to explore thermal quenching performance. Significantly, luminescent temperature sensing has been accomplished by specifically utilizing thermal quenching performance and high temperature sensitivity around 1.54 × 104 K−1 is achieved, which indicates that K0·3Bi0·7F2.4:Eu3+ fluorescent nanoparticles can be exploited for promising luminescent thermometer. Another important results are the K0·3Bi0·7F2.4:40%Eu3+ nanoparticles exhibiting orange red emission with the CIE coordinates (0.6226, 0.3747) and the luminescence photographs of K0·3Bi0·7F2.4:40%Eu3+ samples under UV lamp (365 nm) irradiation revealing obvious orange red. Besides, the color purity of orange red K0·3Bi0·7F2.4:40%Eu3+ phosphor is demonstrated to be about 98.4%, which indicate that the as-prepared K0·3Bi0·7F2.4:Eu3+ phosphors may be a candidate component applied in UV w-LEDs.

Recent years have witnessed the progress of lanthanide-doped materials from fundamental material synthesis to targeted practical applications such as optical applications in photodetection, anti-counterfeiting, volumetric display, optical communication, as well as biological imaging. The unique compositions and structures of well-designed lanthanide ion-doped materials could expand and strengthen their application performances. Herein, we report dual-mode luminescent crystalline microrods that spatially confine upconversion and downconversion photophysical process within defined regions using the specially designed heterogeneous structure. Through an epitaxial growth procedure, downconversion tips have been conjugated with the parent upconversion microrods in oriented directions. This spatially confined structure can effectively depress the deleterious energy depletion in lanthanide ions homogeneously doped materials, and as a result, the red, green, and blue upconversion intensities have been enhanced by 334, 225, and 22 times, respectively. Moreover, the induced tips hardly disturb the upconversion process of the microrod seeds. Upon 980 nm laser or ultraviolet lamp excitation, tunable emission colors were realized in the single tip-modified microrod, indicating potential applications of these microrods for high-level dual-mode anti-counterfeiting.

Biodegradable polymer composites based on poly(ɛ-caprolactone) (PCL) and poly(lactic acid) (PLA) fibers with diameters of 18, 26, 180 μm were prepared by melt compounding. The PLA fiber content in the composites was constant at 20% by weight. The effects of fibers with different diameters on the physical properties and enzymatic degradation of PCL were investigated. The morphological analysis indicated good interfacial adhesion between PCL and PLA fiber, which was beneficial to improve the physical properties of PCL. With increasing PLA fiber diameter, the complex viscosity and modulus of PCL were significantly increased, especially at low frequencies, indicating that the hindered effect of the fiber on the mobility of the PCL molecular chains was more obvious when PLA fiber diameter was thicker. However, as for the mechanical properties, the reinforcement was more obvious to PCL with the smaller PLA fiber diameter. This was because increasing efficient load transfer may be appeared due to the larger surface area and better interface bonding force of the fiber with thinner diameters. The enzymatic degradation of PCL was accelerated with the addition of large PLA fiber diameter of 26 and 180 μm, and hardly changed with the small PLA fiber diameter of 18 μm.

Fully biodegradable polymer blends based on biosourced polymers, namely poly(L-lactide) (PLLA) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)) are prepared by melt compounding. The enzymatic degradation and porous morphology of PLLA/P(3HB-co-4HB) blends are investigated in detail. The lipase from Pseudomonas mendocina reveals preferred enzymatic degradation of P(3HB-co-4HB) but insignificant attack to PLLA in the blends. At the same time, proteinase K can degrade PLLA, but cannot degrade P(3HB-co-4HB). On account of the surface erosion mechanisms, the enzymatic degradation rates of both the P(3HB-co-4HB) and PLLA in the blends are improved because of the presence of the other component to increase the specific surface area. The results of the 1H NMR and GPC indicate that there is no more intermediate products formed during the enzymatic degradation of the PLLA and P(3HB-co-4HB). Due to the specificity of the degradation enzymes, selective enzymatic degradation is adopted to degrade and remove one component from the blends, and various porous morphologies are acquired.

We synthesized the uniform core-shell microstructured compounds with hexagonal phase NaYF₄:Er/Yb microrods as the core and hexagonal phase NaLnF₄ (NaYbF₄, NaLuF₄:Yb/Tm, NaYF₄:Yb/Er, NaYF₄:Eu) as the shell based on the hydrothermal reaction. These microscale core-shell structures provided a platform for the spatially confining optical process while possessing high luminescence efficiency. The thickness of the shell could be controlled by adjusting the amounts of shell precursor, which significantly affected the intensity of the shell dopant ions emission and the emission color of core-shell upconversion luminescence (UCL). The uniform NaYF₄@NaLnF₄ (Ln = Y, Lu, Yb) microrods, with a series of rare-earth ions doped into the core and shell layer at various doping concentrations, achieved color-tuning of the upconversion (UC) emission and dual-mode emission at the single-microcrystal level, thus allowing the efficient utilization of core-shell microcrystals in the photonics and security labeling. This study suggests a new class of luminescent materials in the microscopic field.

Biodegradable polymer composites based on poly(-caprolactone) (PCL) and poly(lactic acid) (PLA) fibers were prepared by melt compounding. The effects of PLA fibers on the crystallization, mechanical properties, and enzymatic degradation of PCL composites were investigated. The addition of PLA fibers enhanced the crystallization of PCL due to the heterogeneous nucleation effect of fibers. However, the final crystallinity of the PCL in the composites was little changed in the presence of PLA fibers. With the addition of PLA fibers, significant improvement in storage modulus (E) of PCL in the composites was achieved. A significant increase in E was 173% for the composites as compared to that of the neat PCL at 20 degrees C. With the increase in PLA fibers content, the PCL composites showed decreased elongation and strength at break; however, the tensile yield strength and modulus were increased significantly, indicating that PCL was obviously reinforced by adding PLA fibers. Although the PLA fibers retarded the enzymatic degradation of PCL, it was possible to be completely degraded without much degradation time for PCL blending with suitable amounts of PLA fibers. POLYM. COMPOS., 34:1745-1752, 2013. (c) 2013 Society of Plastics Engineers

Here we propose a new method for trapping the resonant metallic particles with the 4π tight focusing (high numerical-aperture (NA)) system, which is illuminated by radial polarization light. Numerical simulations have indicated the maximum total optical force is 16.1pN while with nearly zero scattering force under axis trapping, which keeps the gradient force predominant. Furthermore, the distribution of total force is centrosymmetric and odd. We also gain stable 3D trap with an equilibrium point along z axis and r axis as in normal optical tweezers. What’s more, we obtain the nearly pure longitudinal field. The maximum transverse intensity is only 2.3 × 10−3 and the transverse spot size reaches 0.36λ, which is below Abbe’s diffraction limit.

Porous poly( l -lactic acid) (PLLA) sheets were prepared by uniaxial stretching PLLA sheets containing starch filler. Here, the starch filler content, stretching ratio, stretching rate and stretching temperature are important factors to influence the structure of the porous PLLA sheets, therefore, they have been investigated in detail. The pore size distribution and tortuosity were characterized by Mercury Intrusion Porosimetry. The results revealed that the porosity and pore size enlarged with the increase of the starch filler content and stretching ratio, while shrank with the rise of stretching temperature. On the other hand, the pore structure almost had no changes with the stretching rate ranging between 5 and 40 mm/min. In order to test and verify that the porous PLLA sheet was suitable for the tissue engineering, the starch particles were removed by selective enzymatic degradation and its in vitro biocompatibility to osteoblast-like MC3T3-E1 cells was investigated.

We investigate three-dimensional focus shaping generated from double-mode cylindrical vector beams with the Gaussian and Bessel-Gaussian pupil apodization functions by choosing the suitable polarization states of beams. Further, we compare them with that generated from the Laguerre-Gaussian pupil apodization function in the same situation. We find that the focus shaping generated from the Gaussian beam has the smallest zero intensity spot size. However, the situation of the Bessel-Gaussian beam not only possesses stability, which makes it suitable when applied in optical trapping, but also shows the best uniformity, which indicates its excellent performance in super-resolution fluorescence microscopy.

Biodegradable and biosourced poly(3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) fiber was used as a reinforcing agent, and environment friendly poly(ɛ-caprolactone) (PCL) composites were prepared by melt compounding. The mechanical properties, rheological properties, and enzymatic degradation of the PCL composites were investigated in detail. With the addition of PHBV fibers, the PCL composites showed increased tensile yielding strength and modulus. Especially, the storage modulus from the results of dynamic mechanical analysis was increased significantly, suggesting that PCL was obviously reinforced by adding PHBV fibers. With increasing the PHBV fiber content, the complex viscosity and modulus of PCL increased, especially at low frequencies, indicating that a network structure was formed in the composites. The network structure resulted in evident solid-like response due to the restriction of the chain mobility of PCL matrix, which was further confirmed by the Han and Cole–Cole plots. The morphology, evaluated by scanning electron microscopy, indicated PCL and PHBV fiber were not highly incompatible and the interfacial adhesion was good, which was beneficial to the reinforcement effect. The biodegradability of the PCL was significantly promoted after composites preparation. Such studies are of great interest in the development of environment friendly composites from biodegradable polymers.