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Mesoporous silica nanoparticles have highly versatile structural properties that are suitable for a plethora of applications including catalysis, separation, and nanotherapeutics. We report a one-pot synthesis strategy that generates bimodal mesoporous silica nanoparticles via coassembly of a structure-directing Gemini surfactant (C 16-3-16 ) with a tetraethoxysilane/(3-aminopropyl)triethoxysilane-derived sol additive. Synthesis temperature enables control of the nanoparticle shape, structure, and mesopore architecture. Variations of the aminosilane/alkylsilane molar ratio further enable programmable adjustments of hollow to core-shell and dense nanoparticle morphologies, bimodal pore sizes, and surface chemistries. The resulting Gemini-directed aminated mesoporous silica nanoparticles have excellent carbon dioxide adsorption capacities and antimicrobial properties against Escherichia coli . Our results provide an enhanced understanding of the structure formation of multiscale mesoporous inorganic materials that are desirable for numerous applications such as carbon sequestration, water remediation, and biomedical-related applications.

Measuring the three-dimensional motion of trees at every position remains challenging as it requires dynamic measurement technology with sufficient spatial and temporal resolution. Consequently, this study explores the use of a novel multi-beam flash light detection and ranging (LiDAR) sensor to tackle such a sensing barrier. A framework is proposed to record tree vibrations, to construct the motions of tree skeletons from the point-cloud frames recorded by the LiDAR sensor and to derive the dynamic properties of trees. The feasibility of the framework is justified through measurement on a Ficus microcarpa under pull-and-release tests. The relative differences for the first two modal frequencies between the LiDAR and linear variable differential transformer measurements in the displacement Fourier spectra are 0.1% and 2.5%, respectively. The framework is further adopted to study the dynamic response of different trees subjected to typhoons, including a Liquidambar formosana , three Araucaria heterophylla trees, a Sterculia lanceolata , a Celtis sinensis , a Tabebuia chrysantha and a Cinnamomum camphora . Results suggest that broadleaved trees might exhibit vibration in a wide frequency band, whereas the coniferous trees could follow a distinct dominant frequency.

Block copolymer self-assembly-derived thin films provide direct access to two- and three-dimensional periodically ordered mesostructures as enablers for many nanotechnology applications. This report describes laser-annealing-induced disorder-order mesophase transitions of polystyrene- block -poly(ethylene oxide)/resol hybrid thin films over a range of laser temperatures (∼45 to 525 °C) and short dwell times (0.25 to 100 ms), revealing the non-equilibrium ordering and disordering kinetics and behaviors. We found that a combination of transient laser temperature of ∼275 °C and annealing dwell time of 100 ms provided the most optimal kinetic and thermodynamic control of the diffusivities of hybrid mesophases and photothermal-induced resol polymerization, yielding long-range ordered films resembling an in-plane body-centered cubic sphere morphology. A clear understanding of hybrid thin film mesophase self-assembly under non-equilibrium laser annealing could open new avenues to introduce novel chemistries and rapidly achieve nanoscale periodic order suitable for the patterning of complex structures, electronics, sensing, and emerging quantum materials., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Objective: To explore the effect of Wangbuliuxing ( semen vaccariae ) combined with massage at breast and acupoint on breastfeeding and lactation function in cesarean section women., Methods: A total of 120 cases of cesarean section women were randomly divided into an observation group and a control group, 60 cases in each group. The control group was treated with routine nursing. On the basis of the control group, the observation group was treated with oral administration of Wangbuliuxing decoction, twice a day for 7 days; in addition, massage at breast and acupoint (Zhongfu [LU 1], Yunmen [LU 2], Danzhong [CV 17], 2 min per acupoint per time) was given, twice a day for 7 days. The onset time of lactation, 48-hour postpartum lactation volume, breast swelling and pain, 42-day postpartum breastfeeding were compared between the two groups; the serum levels of prolactin at 48 and 72 h after delivery were measured, and the body mass of newborns at birth and 42 d after delivery were recorded., Results: The onset time of lactation in the observation group was earlier than that in the control group ( P <0.05), the 48-hour postpartum lactation volume was higher than the control group ( P <0.05), and the breast swelling pain 48 h after delivery was lighter than the control group ( P <0.05). Forty-two days after delivery, the success rate of breastfeeding in the observation group was 91.7% (55/60), which was higher than 76.7% (46/60) in the control group ( P <0.05). At 48 and 72 h after delivery, the level of serum prolactin in the observation group was higher than that in the control group ( P <0.05). On 42 d after delivery, the body mass of newborns in the two groups was higher than that at birth ( P <0.05), and that in the observation group was higher than the control group ( P <0.05)., Conclusion: Wangbuliuxing combined with massage at acupoint and breast could significantly shorten the onset time of lactation, improve the lactation volume, effectively improve breast swelling and pain, increase breastfeeding rate and promote the growth and development of newborns.

We describe a versatile and scalable strategy toward long-range and periodically ordered mesoporous alumina (Al 2 O 3 ) structures by evaporation-induced self-assembly of a structure-directing ABA triblock copolymer (F127) mixed with aluminum tri- sec -butoxide-derived sol additive. We found that the separate preparation of the alkoxide sol-gel reaction before mixing with the block copolymer enabled access to a relatively unexplored parameter space of copolymer-to-additive composition, acid-to-metal molar ratio, and solvent, yielding ordered mesophases of two-dimensional (2D) lamellar, hexagonal cylinder, and 3D cage-like cubic lattices, as well as multiscale hierarchical ordered structures from spinodal decomposition-induced macro- and mesophase separation. Thermal annealing in air at 900 °C yielded well-ordered mesoporous crystalline γ-Al 2 O 3 structures and hierarchically porous γ-Al 2 O 3 with 3D interconnected macroscale and ordered mesoscale pore networks. The ordered Al 2 O 3 structures exhibited tunable pore sizes in three different length scales, <2 nm (micropore), 2-11 nm (mesopore), and 1-5 μm (macropore), as well as high surface areas and pore volumes of up to 305 m 2 /g and 0.33 cm 3 /g, respectively. Moreover, the resultant mesoporous Al 2 O 3 demonstrated enhanced adsorption capacities of carbon dioxide and Congo red dye. Such hierarchically ordered mesoporous Al 2 O 3 are well-suited for green environmental solutions and urban sustainability applications, for example, high-temperature solid adsorbents and catalyst supports for carbon dioxide sequestration, fuel cells, and wastewater separation treatments.

Automatic bird detection in ornithological analyses is limited by the accuracy of existing models, due to the lack of training data and the difficulties in extracting the fine-grained features required to distinguish bird species. Here we apply the domain randomization strategy to enhance the accuracy of the deep learning models in bird detection. Trained with virtual birds of sufficient variations in different environments, the model tends to focus on the fine-grained features of birds and achieves higher accuracies. Based on the 100 terabytes of 2-month continuous monitoring data of egrets, our results cover the findings using conventional manual observations, e.g., vertical stratification of egrets according to body size, and also open up opportunities of long-term bird surveys requiring intensive monitoring that is impractical using conventional methods, e.g., the weather influences on egrets, and the relationship of the migration schedules between the great egrets and little egrets.

Nanocarriers can be translocated to the peripheral region of tumor tissues through the well-known enhanced permeability and retention effects. However, a high dose of nanocarriers need to be injected due to the low delivery efficiency of nanocarriers, which can also increase the side effects of off-targeted nanocarriers in normal tissues. It was demonstrated that on-demand drug release from tumor-targeted nanocarriers can reduce the effective dosage of anti-cancer drugs by rapidly increasing the local drug concentration in the tumor tissue. Here we report a near-infrared (NIR) photodynamic method to trigger drug release from tumor-targeted polymer nanoparticles via reactive oxygen species (ROS)-mediated polymer degradation. Paclitaxel and silicon 2,3-naphthalocyanine bis(trihexylsilyloxide) were co-encapsulated as an anti-cancer drug and photosensitizer, respectively, within biotin-decorated poly(ethylene glycol)-polythioketal micelles. Upon NIR light illumination under the maximum permissible exposure level, the photoexcited naphthalocyanine generated ROS cleaved the thioketal groups in the micelles to release the encapsulated paclitaxel. The photodynamically-induced release of paclitaxel dramatically reduced the half maximal inhibitory concentration of paclitaxel by 39.9-fold and eliminated lung adenocarcinoma at a concentration an order of magnitude smaller than its maximum tolerated dosage. Even under a simulated deep tissue condition with a tissue-like phantom, the NIR light-illuminated micelles exhibited a high level of cytotoxicity against the tumor cells and efficiently suppressed tumor growth. Our study demonstrates that photodynamic polymer degradation is an effective means to improve the anticancer drug efficacy of tumor-targeted micelles.

Tumor-targeted delivery of anticancer agents using nanocarriers has been explored to increase the therapeutic index of cancer chemotherapy. However, only a few nanocarriers are clinically available because the physiological complexity often compromises their ability to target, penetrate, and control the release of drugs. Here, we report a method which dramatically increases in vivo therapeutic drug efficacy levels through the photodynamic degradation of tumor-targeted nanocarriers. Folate-decorated poly(ethylene glycol)-polythioketal micelles are prepared to encapsulate paclitaxel and porphyrins. Photo-excitation generates reactive oxygen species within the micelles to cleave the polythioketal backbone efficiently and facilitate drug release only at the illuminated tumor site. Intravenous injection of a murine xenograft model with a low dose of paclitaxel within the micelles, one-milligram drug per kg (mouse), corresponding to an amount less than that of Taxol by one order of magnitude, induces dramatic tumor regression without any acute systemic inflammation responses or organ toxicity under low-power irradiation (55 mW cm -2 ) at 650 nm., (Copyright © 2018. Published by Elsevier B.V.)

The current-voltage characteristics of Ni contacts with the surfaces of ZnO thin films as well as single crystal (0001) ZnO substrate are investigated. The ZnO thin film shows a conversion from Ohmic to rectifying behavior when annealed at 800°C. Similar findings are also found on the Zn-polar surface of (0001) ZnO. The O-polar surface, however, only shows Ohmic behavior before and after annealing. The rectifying behavior observed on the Zn-polar and ZnO thin film surfaces is associated with the formation of nickel zinc oxide (Ni1-xZnxO, where x = 0.1, 0.2). The current-voltage characteristics suggest that a p-n junction is formed by Ni1-xZnxO (which is believed to be p-type) and ZnO (which is intrinsically n-type). The rectifying behavior for the ZnO thin film as a result of annealing suggests that its surface is Zn-terminated. Current-voltage measurements could possibly be used to determine the surface polarity of ZnO thin films.

Background: Colibacillosis is one of the main causes of economic loss in the poultry industry worldwide. Although antibiotics have been used to control this infection, the emergence of antibiotic-resistant bacteria poses a threat to animal and human health. Phage therapy has been reported as one of the potential alternative methods to control bacterial infections. However, efficient phage therapy is highly dependent on the characteristics of the phage isolated. In the present study the characteristics of a lytic phage, ØEC1, which was found to be effective against the causative agent of colibacillosis in chickens in a previous in vivo study, are reported., Results: Examination by transmission electron microscopy revealed that ØEC1 is a DNA phage belonging to the Podoviridae family. ØEC1 showed an optimum multiplicity of infection of 0.1-1. The latent period of ØEC1 was 25 min, with a burst size of 200 particles per infected cell. Under the experimental conditions the maximum adsorption rate for ØEC1 was 99.9% within 8 min. ØEC1 demonstrated an optimum phage lytic activity at pH 6-9 and 25-41 °C., Conclusion: These characteristics can serve as a guideline for selection of effective candidates for phage therapy, in this case for collibacillosis control in chickens., (Copyright © 2012 Society of Chemical Industry.)