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A compact U-shaped interferometer with high refractive index (RI) sensitivity based on bent single-mode fiber is proposed and demonstrated experimentally. The sensor is fabricated by roasting a balloon-shaped single-mode optical fiber to form a U-shaped modal interferometer. Since the spectral dips show different sensitivities to both the surrounding RI and temperature, simultaneous measurement of RI and temperature can be achieved by demodulating the shifts of the different resonance dips without cascading additional components. The sensitivity of RI reaches up to −1705.66 nm/RIU in the range of 1.3330-1.3581, which is about 10 times as the reported arts. The proposed compact U-shaped interferometer is a potentially effective sensor for chemical and biological applications where an accurate RI measurement of a temperature-changing liquid is required.

Herein we investigated the effects of adding resistant and waxy maize starches on the initial cell density and stress tolerance of alginate-gum microcapsules containing high-density biofilm colonies of Lactobacillus rhamnosus GG probiotics. The stress tolerance was evaluated for (1) freeze drying, (2) 30-min heating at 100 °C, (3) two-week storage at 4 °C, and (4) exposure to simulated gastric juice. The addition of resistant starch, which was postulated to stimulate biofilm growth owed to its prebiotic properties, had minimal impacts on the initial cell density and stress tolerance of the encapsulated probiotics, signifying that co-encapsulation of probiotics with prebiotics did not necessarily lead to capsule improvement. In contrast, the addition of modified waxy starch at 0.6% (w/v) enhanced the freeze-drying (2×), thermal (25×), and storage (6×) tolerances of the probiotic microcapsules, while the initial cell density remained unaffected. The waxy starch addition, however, compromised the microcapsules' chitosan coating, resulting in lower acid tolerance. Lastly, the microcapsules were able to maintain the viability of the probiotics upon their incorporation into soy milk.

We report on the electrical transport properties of new graphene/blue phosphorene heterostructure devices by density functional theory (DFT) within the non-equilibrium Green’s function (NEGF) approach. From the results, it is found that the devices with different length of contacts layers show semiconducting nature. The integrated contacted length of graphene/blue phosphorene two-layer device shows the best conductivity under a bias voltage. The negative differential resistance effect (NDR) is also found in the current-voltage curve of all the graphene/blue phosphorene devices. Transport characteristics can be explained by the eigenvalues of self-consistent Hamiltonian (MPSH). The results show that the device is fabricated from graphene/blue phosphorous and has good electrical conductivity. These interesting features will be useful for future electronic products.

While the supersaturation generation capability of amorphous nanopharmaceuticals (NPs) in their aqueous suspension form has been well established, their supersaturation generation is adversely affected after drying. Herein we investigated the effects of freeze drying on the supersaturation generation capability of a new class of amorphous NPs referred to as drug nanoplex prepared and stabilized by electrostatic complexation of drug molecules with polysaccharides (dextran sulfate). Using ciprofloxacin as the model drug, two types of freeze-drying adjuvants were investigated, i.e., (1) highly water-soluble excipient (trehalose, mannitol), whose role was to prevent irreversible NPs aggregations upon drying, and (2) crystallization inhibitor (hydroxypropylmethylcellulose (HPMC)), whose role was to suppress crystallization of the dissolved drug and the remaining solid phase. The results showed that dual-adjuvant formulations (i.e. trehalose-HPMC and mannitol-HPMC) were required to preserve the supersaturation generation capability of the drug nanoplex suspension after drying. Freeze drying with only one adjuvant type, or incorporating HPMC as physical mixtures with the freeze-dried nanoplex, were ineffective in preserving the supersaturation. The dual-adjuvant formulations produced prolonged supersaturation levels over 240min at ≈6-8× of the saturation solubility with comparable area under the curve (AUC) in the concentration versus time plot as that exhibited by the suspension form.

Health benefits conferred by probiotic organism Lactobacillus rhamnosus GG taken as food supplements to its human hosts have been well established clinically. Probiotic capsules containing biofilm form of L. rhamnosus GG was shown very recently to exhibit greater freeze drying and thermal tolerance than their planktonic cell counterparts. Herein we examine the impacts of biofilm age (1, 3, and 5 days) and growth medium ( Lactobacilli broth de Man, Rogosa and Sharpe (MRS) or Lactobacilli broth according to the Association of Official Analytical Chemists (AOAC)) on the biofilm capsules' tolerance towards stresses typically encountered in food product lifecycle, i.e. freeze drying, two-week storage at 4 °C, heating at 100 °C, and simulated gastrointestinal juice exposure. While freeze drying and thermal tolerance are minimally affected, storage and gastrointestinal viabilities are highly dependent on biofilm age and growth medium. Capsules prepared in AOAC exhibit higher cell viabilities than those prepared in MRS attributed to higher extracellular polymeric substance (EPS) in the former. Mature biofilm capsules (>1 day) survive storage better, however, their gastrointestinal juice viability is compromised, particularly for MRS capsules. The best overall viability is obtained from 5-day-old biofilm capsules in AOAC.

Based on optimization theories, considering soil-structure interaction and running safety, the optimal design model of the seismic isolation system with lead-rubber bearings (LRB) for a simply supported railway beam bridge is established by using the first order optimization method in ANSYS, which the parameters of the isolation bearing are taken as design variables and the maximum moments at the bottom of bridge piers are taken as objective functions. The optimal calculations are carried out under the excitation of three practical earthquake waves respectively. The research results show that the ratio of the stiffness after yielding to the stiffness before yielding has important effect on the structural seismic responses. Through the optimal analysis of isolated bridge system, the optimal design parameters of isolation bearing can be determined properly, and the seismic forces can be reduced maximally as meeting with the limits of relative displacement between pier top and beam, which provides efficient paths and beneficial references for dynamic optimization design of seismic isolated bridges.

With the development of increasingly large and complex genomic and proteomic data sets, an enhancement in the complexity of available Venn diagram analytical programs is becoming increasingly important. Current freely available Venn diagram programs often fail to represent extra complexity among datasets, such as regulation pattern differences between different groups. Here we describe the development of VennPlex, a program that illustrates the often diverse numerical interactions among multiple, high-complexity datasets, using up to four data sets. VennPlex includes versatile output features, where grouped data points in specific regions can be easily exported into a spreadsheet. This program is able to facilitate the analysis of two to four gene sets and their corresponding expression values in a user-friendly manner. To demonstrate its unique experimental utility we applied VennPlex to a complex paradigm, i.e. a comparison of the effect of multiple oxygen tension environments (1–20% ambient oxygen) upon gene transcription of primary rat astrocytes. VennPlex accurately dissects complex data sets reliably into easily identifiable groups for straightforward analysis and data output. This program, which is an improvement over currently available Venn diagram programs, is able to rapidly extract important datasets that represent the variety of expression patterns available within the data sets, showing potential applications in fields like genomics, proteomics, and bioinformatics.

The published VENNTURE link is no longer accurate. VENNTURE version 1.1.0.2 can be accessed freely at the National Institute on Aging (http://www.grc.nia.nih.gov/).

As pharmacological data sets become increasingly large and complex, new visual analysis and filtering programs are needed to aid their appreciation. One of the most commonly used methods for visualizing biological data is the Venn diagram. Currently used Venn analysis software often presents multiple problems to biological scientists, in that only a limited number of simultaneous data sets can be analyzed. An improved appreciation of the connectivity between multiple, highly-complex datasets is crucial for the next generation of data analysis of genomic and proteomic data streams. We describe the development of VENNTURE, a program that facilitates visualization of up to six datasets in a user-friendly manner. This program includes versatile output features, where grouped data points can be easily exported into a spreadsheet. To demonstrate its unique experimental utility we applied VENNTURE to a highly complex parallel paradigm, i.e. comparison of multiple G protein-coupled receptor drug dose phosphoproteomic data, in multiple cellular physiological contexts. VENNTURE was able to reliably and simply dissect six complex data sets into easily identifiable groups for straightforward analysis and data output. Applied to complex pharmacological datasets, VENNTURE’s improved features and ease of analysis are much improved over currently available Venn diagram programs. VENNTURE enabled the delineation of highly complex patterns of dose-dependent G protein-coupled receptor activity and its dependence on physiological cellular contexts. This study highlights the potential for such a program in fields such as pharmacology, genomics, and bioinformatics.

A new polarization rotator based on the silica photonic crystal fiber is proposed. The proposed polarization rotator photonic crystal fiber (PR-PCF) possesses a triangle jigsaw-shape core region. The full-vector finite-element method is used to analyze the phenomenon of polarization conversion between the quasi-TE and quasi-TM modes. Numerical simulations show that the wavelengths of 1.31 μm and 1.55 μm are converted with a nearly 100% polarization conversion ratio with their matched coupling length and has a relatively strong realistic fabrication tolerance −100 nm on the y axis and 50 nm on the x axis. The full vectorial finite difference beam propagation method is used to confirm the performance of the proposed PR-PCF.