Coexistence of MRCS syndrome, extremely long axis and exfoliation syndrome: a case report and literature review.

BACKGROUND: The coexistence of MRCS (microcornea, retinal dystrophy, cataract, and posterior staphyloma) syndrome and extremely long axis is rare since microcornea frequently accompanies with diminution of entire anterior segment and occasionally the whole globe. In the case presented here, combination of these two elements were identified, together with XFS (exfoliation syndrome). CASE PRESENTATION: A 66-year-old Han Chinese woman presented for consultation due to impaired vision which accompanied throughout her entire life span and worsened during the last 2 years. Combination of MRCS syndrome and extremely long axial length was evidently diagnosed in both eyes, with XFS confirmed in her right eye, but mutation screening failed to identify disease-causing sequence variants in some specific genes reported previously, including BEST1 and ARL2. However, likely pathogenic mutations in FBN2 gene were identified. Bilateral cataract phacoemulsification without intraocular lens implantation was performed using scleral tunnel incision and under general anesthesia. At 3-month follow-up, ocular recovery of the patient was satisfactory. CONCLUSIONS: The case presented here exhibited rare coexistence of MRCS syndrome, extremely long axis and XFS. The complexity of her ocular abnormalities brought challenges to surgical management, in which multidisciplinary collaboration is often required. Furthermore, the genetic analysis in this case yielded a possible novel candidate gene for MRCS syndrome and provided evidence in support of genetic heterogeneity in this phenotype.

Predictive value of ellipsoid zone-related angle parameters in primary surgery of large macular hole: a case control study.

BACKGROUND: To explore the predictive value of Ellipsoid Zone (EZ) -related angle parameters for the outcome of primary macular hole surgery. METHODS: This was a retrospective study. Patients diagnosed with large macular hole (MH) (minimum diameter > 500 µm) between 2018 and 2021 were enrolled. All patients underwent 25-gauge pars plana vitrectomy, internal limiting membrane (ILM) peeling and air tamponade. Spectral-domain OCT (SD-OCT) and best corrected visual acuity (BCVA) were measured in preoperative and 2-week post-operative. Classic and angle related parameters were measured via ImageJ. Angle regularity (AR) were defined as the standard deviation of the angle parameters in vertical and horizontal direction. RESULTS: Seventy-six eyes were included for analysis; 24 eyes showed an unclosed macular hole at the 2-week postoperative and 52 eyes showed a closed hole. Preoperatively, MLD (P < 0.001), BD (P = 0.009) and diameter of EZ/ELM disruption (P = 0.002 and 0.025) in patients failed to close the hole after primary surgery were significantly larger than those succeeded. EZ-MH (P = 0.018), EZ-NFL (P = 0.006), EZ-GCL (P = 0.004), EZ-INL (P = 0.002), EZ-OPL (P = 0.009) and EZ-ONL (P = 0.011) angles were smaller in patients with unclosed hole. AR of the EZ-NFL (P = 0.009), EZ-GCL (P = 0.009), EZ-OPL (P = 0.023), EZ-ONL (P = 0.048) and Basal-NFL (P = 0.030) angles among the unclosed patients were significantly larger than those of the closed group. EZ-NFL (P = 0.015), EZ-GCL (P = 0.004), EZ-INL (P < 0.001), EZ-OPL (P < 0.001), EZ-ONL (P < 0.001), Basal (P = 0.023) and Basal-NFL (P < 0.001) angles of hole-unclosed patients enlarged significantly after the surgery. CONCLUSIONS: Patients with large macular holes and an increased EZ-related angle and angle AR are more likely to experience unsuccessful outcomes following primary MH surgery. Therefore, EZ-related angles hold potential as valuable parameters for predicting the surgical outcome.

A novel variant in CFAP69 causes asthenoteratozoospermia with treatable ART outcomes and a literature review.

PURPOSE: Multiple morphological abnormalities of the sperm flagella (MMAF) are a severe form of sperm defect causing male infertility. Previous studies identified the variants in the CFAP69 gene as a MMAF-associated factor, but few cases have been reported. This study was performed to identify additional variants in CFAP69 and describe the semen characteristics and outcomes of assisted reproductive technology (ART) in CFAP69-affected couples. METHODS: Genetic testing with next-generation sequencing (NGS) panel of 22 MMAF-associated genes and Sanger sequencing was performed in a cohort of 35 infertile males with MMAF to identify pathogenic variants. Morphological, ultrastructural, and immunostaining analyses were performed to investigate the characteristics of probands' spermatozoa. ART with intracytoplasmic sperm injection (ICSI) was carried out for the affected couples to get their own progenies. RESULTS: We identified a novel frameshift variant in CFAP69 (c.2061dup, p. Pro688Thrfs*5) from a MMAF-affected infertile male with low sperm motility and malformed morphology of sperm. Furthermore, transmission electron microscopy and immunofluorescence staining revealed that the variant induced the aberrant ultrastructure and reduction of CFAP69 expression in the proband's spermatozoa. Moreover, the partner of the proband birthed a healthy girl through ICSI. CONCLUSIONS: This study expanded the variant spectrum of CFAP69 and described the good outcome of ART treatment with ICSI, which is beneficial to the molecular diagnosis, genetic counseling, and treatment of infertile males with MMAF in the future.

A SIRT1 Activator, Ginsenoside Rc, Promotes Energy Metabolism in Cardiomyocytes and Neurons.

Targeting SIRT1 signaling pathway could improve glucose aerobic metabolism and mitochondrial biosynthesis to resist cardiac and neurological injuries. Ginsenoside Rc has been identified for targeting mitochondrial function, but how ginsenoside Rc interacts with SIRT1 to regulate energy metabolism in cardiomyocytes and neurons under physiological or ischemia/reperfusion (I/R)-injured conditions has not been clearly investigated. Here, we confirm the interaction of Rc on the residue sites of SIRT1 in promoting its activity. Ginsenoside Rc significantly promotes mitochondrial biogenesis and increases the levels of electron-transport chain complex II-IV in cardiomyocytes and neurons. Meanwhile, ginsenoside Rc pretreatment increases ATP production, glucose uptake, and the levels of hexokinase I/II and mitochondrial pyruvate carrier I/II in both cell models. In addition, ginsenoside Rc activates the PGC1α pathway to induce mitochondrial biosynthesis. More importantly, ginsenoside Rc reduces mitochondrial damage and apoptosis through SIRT1 restoration-mediated reduction of PGC1α acetylation in the I/R-induced cardiac and neuronal models. Collectively, the in vitro and in vivo data indicate that ginsenoside Rc as a SIRT1 activator promotes energy metabolism to improve cardio- and neuroprotective functions under normal and I/R injury conditions, which provides new insights into the molecular mechanism of ginsenoside Rc as a protective agent.

Treatment of maxillofacial congenital melanocytic nevus with percutaneous radiofrequency thermal ablation: A case series study.

When congenital melanocytic nevus (CMN) is in the maxillofacial region, a safer, more effective and fewer side-effects treatment is needed for patients with high requirement for appearance. The objective of this study was to investigate the effectiveness of radiofrequency thermal ablation (RFA) for CMN in the maxillofacial region. We reviewed 21 patients treated with RFA for CMN followed by a blinded retrospective analysis of serial photographs taken during the course of their therapy. Questionnaires were used to evaluate perceived therapeutic response and complications of this treatment. Most CMNs stopped growing, faded in color and became smaller. Reduction in size of 90% to 100% was obtained in two patients (10%), 75% to 90% in six patients (29%), 50% to 75% in two patients (10%), <50% in eight patients (38%), and three had no reduction (13%). Clear effect of clinical response score was obtained in two patients (10%), excellent in four patients (19%), good in 14 patients (67%), and fair in one patient (4%). No serious complication, severe hypertrophic scarring, and evidence of recurrence was observed in any case. Percutaneous RFA, as a minimally invasive and safe treatment, may provide an alternative treatment for maxillofacial CMN.

Radially self-accelerating Stokes vortices in nondiffracting Bessel-Poincaré beams.

We theoretically propose and experimentally generate the nondiffracting Bessel-Poincaré beams whose Stokes vortices radially accelerate during propagation. To this end, we design the Bessel beams whose intensity is specified to be uniformly distributed along the longitudinal direction. By superposing two such Bessel beams having different helical phases and mutually orthogonal polarizations, the synthesized vector beam is endowed with the polarization singularity that can rotate about the optical axis, while the total intensities maintain their profiles. Radially self-accelerating Stokes vortices in the resulting beam can be manipulated by adjusting the predefined parameters in the constituent beams.

Incidence, Risk Factors, Outcomes, and Risk Score Model of Acute Pancreatitis after Allogeneic Hematopoietic Stem Cell Transplantation.

Acute pancreatitis (AP) has been recognized as an uncommon yet potentially lethal complication after hematopoietic stem cell transplant (HSCT). This retrospective, nested, case-control study reviewed data from 5284 consecutive patients who underwent allogeneic (allo)-HSCT between 2009 and 2018 at a single center, identifying 40 patients (0.76%) with AP after allo-HSCT. The diagnosis and severity of AP were established and classified according to existing criteria. Younger age (P = .008), grades II to IV acute graft-versus-host disease (P = .010), a history of donor lymphocyte infusion (P = .033), and pre-existing gallstones (P = .003) were independent risk factors of AP after allo-HSCT. Post-transplant AP had a trend to negatively influence overall survival (OS) and nonrelapse mortality (NRM) (P = .063) for allo-HSCT recipients, but no significant difference was found. Patients with moderately severe and severe AP had significantly lower OS (P = .002) and higher NRM (P = .000) than other patients. Based on these findings, a risk score model was also established to predict the occurrence of AP. Our risk score model performed well in terms of discrimination when applied to derivation samples. Patients were classified into a low-risk group (0 to 1 point), a medium-risk group (2 to 3 points), and a high-risk group (4 points or more). Significant difference was observed in AP incidence among the 3 groups. The predictive tool explored by our study might contribute to target high-risk patients and guide personalized AP prevention in allo-HSCT recipients.

Comparing the Coalescence Rate of Water-in-Oil Emulsions Stabilized with Asphaltenes and Asphaltene-like Molecules.

Asphaltenes are a significant contributor to flow assurance problems related to crude oil production. Because of their polydispersity, model molecules such as coronene and violanthrone-79 (VO-79) have been used as mimics to represent the physiochemical properties of asphaltenes. This work aims to evaluate the emulsion-stabilization characteristics of fractionated asphaltenes and these two model molecules. Such evaluation is expected to better characterize the stabilizing mechanisms of asphaltenes on water-in-oil emulsions. The coalescence process of water-in-oil emulsion droplets is visualized using a microfluidic flow-focusing geometry. The rate of coalescence events is used as the parameter to assess emulsion stability. Interfacial tension (IFT) and oil/brine zeta potential are measured to help explain the differences in the rates of coalescence. VO-79 is found to be better at stabilizing emulsions as compared to coronene. Although VO-79 and asphaltenes have similar interfacial tension and oil/brine zeta potential values, the rate of coalescence differs significantly. This highlights the difficulty in using model molecules to mimic the transport dynamics of asphaltenes.

Effects of Heating-Conduction Dry Needling Therapy on Rats with Chronic Myofascial Pain Syndrome.

OBJECTIVE: This study aimed to investigate the effect of dry needling (DN) with 44°C heating on the pressure pain threshold (PPT) of rats with chronic myofascial pain syndrome (MPS) by regulating the transient receptor potential V1 channel. METHODS: A total of 80 rats were divided into 5 groups: A, B, C, D, and E (16 in each group). The rats in Group A recovered naturally, while those in other groups received the DN treatment. The needles were heated to 40°C for the rats in Groups B and E and 44°C for the rats in Groups C and D. In addition, both Groups D and E received local capsaicin injection. PPTs of the gastrocnemius muscle and tolerance time of the plantar hot plate were measured before modeling, 1 day before the intervention, 24 hours after the intervention, and 7 days after the intervention. RESULTS: PPTs of the gastrocnemius muscle for rats with MPS increased 7 days after DN and heating to 40°C. For the rats receiving DN at 44°C heating, PPTs increased 24 hours and 7 days after the intervention. Further, 44°C heating and capsaicin injection improved PPT. DN and 40°C heating followed by capsaicin injection improved PPT. CONCLUSION: DN and 44°C heating had therapeutic effects on rats with MPS at 24 hours and at 7 days after the intervention. DN and 40°C heating had therapeutic effects 7 days after the intervention. DN and 44°C heating might exert therapeutic effects by regulating the transient receptor potential V1 channel.

Systematic truncating of aptamers to create high-performance graphene oxide (GO)-based aptasensors for the multiplex detection of mycotoxins.

Graphene oxide (GO)-based aptasensors are currently one of the most popular sensing platforms for the simple and rapid detection of various targets. Unfortunately, the GO-based aptasensors with long aptamer strands typically show unsatisfactory performance resulting from insignificant structural transformations upon target binding. We report herein the utilization of an aptamer-truncating strategy to combat such a challenge. Taking a pre-selected anti-aflatoxin B1 (AFB1) aptamer (P-AFB1-50) as a trial system, we sequentially remove the extraneous nucleotides within the aptamer by means of circular dichroism (CD) spectroscopy and binding affinity analysis. Particularly, the ratio of the quenching constants between the GO sheets and the truncated aptamers (labelled with fluorophores) in the absence and presence of the target was determined for each of the truncated aptamers to evaluate the optimal sequence. As a result, the truncated aptamer comprising 40 nucleotides was confirmed to show the highest FL output and the best detection limit upon conjugation with GO sheets. More importantly, we demonstrated that this truncating strategy is versatile, i.e., it can be easily extended to other aptamer systems (anti-ochratoxin A (OTA) aptamer, P-OTA-61, as an example) for extraneous nucleotide identification. Impressively, the two optimal truncated aptamers can work together on GO sheets to achieve a simultaneous detection of two different mycotoxins (i.e., AFB1 and OTA) in one single test. Essentially, this research opens a new avenue for the design and testing of aptamer-/GO-based-sensing platforms for rapid, low-cost and multiplex quantification of analytical targets of interest.

Exonuclease I-Hydrolysis Assisted Electrochemical Quantitation of Surface-Immobilized DNA Hairpins and Improved HIV-1 Gene Detection.

The complete formation of stem-loop (i.e., hairpin) configuration on chip surface is of particular importance for the application of hairpin DNA (hpDNA) in building biosensors for various analytes with optimized performance. We report herein a convenient electrochemical protocol for evaluating the yield of hairpin DNA conformations upon self-assembly on electrode surface. As of the different hydrolysis capability of Exonuclease I (Exo I) toward single-stranded DNA (ssDNA) and hpDNA, we can selectively remove ssDNA from electrode but retain hpDNA strands; based on the changes in the cyclic voltammetric (CV) responses using [Ru(NH3)6]3+ as redox indicators, we can then determine the fraction of hairpin configurations in mixed DNA self-assembled monolayers (SAMs). It was discovered that the molar fraction of hairpin configuration formed on the surface is considerably lower than that in the binary deposition solution (containing both ssDNA and hpDNA). The accuracy of the Exo I-assisted electrochemical quantitative protocol has been validated by standard DNA hybridization experiments; the relationship between the overall DNA packing density and the yield of hairpin configurations was also evaluated. More importantly, taking HIV-1 gene detection as a trial system, the hpDNA-based biosensor shows significantly improved detection limit and broadened response range upon the background reduction by Exo I-catalyzed hydrolysis.

Revealing and Resolving the Restrained Enzymatic Cleavage of DNA Self-Assembled Monolayers on Gold: Electrochemical Quantitation and ESI-MS Confirmation.

Herein, we report a combined electrochemical and ESI-MS study of the enzymatic hydrolysis efficiency of DNA self-assembled monolayers (SAMs) on gold, platform systems for understanding nucleic acid surface chemistry, and for constructing DNA-based biosensors. Our electrochemical approach is based on the comparison of the amounts of surface-tethered DNA nucleotides before and after exonuclease I (Exo I) incubation using electrostatically bound [Ru(NH3)6]3+ as redox indicators. It is surprising to reveal that the hydrolysis efficiency of ssDNA SAMs does not depend on the packing density and base sequence, and that the cleavage ends with surface-bound shorter strands (9-13 mers). The ex-situ ESI-MS observations confirmed that the hydrolysis products for ssDNA SAMs (from 24 to 56 mers) are dominated with 10-15 mer fragments, in contrast to the complete digestion in solution. Such surface-restrained hydrolysis behavior is due to the steric hindrance of the underneath electrode to the Exo I/DNA binding, which is essential for the occurrence of Exo I-catalyzed processive cleavage. More importantly, we have shown that the hydrolysis efficiency of ssDNA SAMs can be remarkably improved by adopting long alkyl linkers (locating DNA strands further away from the substrates).

Inhibition mechanism of P-glycoprotein mediated efflux by mPEG-PLA and influence of PLA chain length on P-glycoprotein inhibition activity.

The present study aimed to investigate the effect of monomethoxy poly(ethylene glycol)-block-poly(D,L-lactic acid) (mPEG-PLA) on the activity of P-glycoprotein (P-gp) in Caco-2 cells and further unravel the relationship between PLA chain length in mPEG-PLA and influence on P-gp efflux and the action mechanism. The transport results of rhodamine 123 (R123) across Caco-2 cell monolayers suggested that mPEG-PLA unimers were responsible for its P-gp inhibitory effect. Furthermore, transport studies of R123 revealed that the inhibitory potential of P-gp efflux by mPEG-PLA analogues was strongly correlated with their structural features and showed that the hydrophilic mPEG-PLA copolymers with an intermediate PLA chain length and 10.20 of hydrophilic-lipophilic balance were more effective at inhibiting P-gp efflux in Caco-2 cells. The fluorescence polarization measurement results ruled out the plasma membrane fluidization as a contributor for inhibition of P-gp by mPEG-PLA. Concurrently, mPEG-PLA inhibited neither basal P-gp ATPase (ATP is adenosine triphosphate) activity nor substrate stimulated P-gp ATPase activity, suggesting that mPEG-PLA seemed not to be a substrate of P-gp and a competitive inhibitor. No evident alteration in P-gp surface level was detected by flow cytometry upon exposure of the cells to mPEG-PLA. The depletion of intracellular ATP, which was likely to be a result of partial inhibition of cellular metabolism, was directly correlated with inhibitory potential for P-gp mediated efflux by mPEG-PLA analogues. Hence, intracellular ATP-depletion appeared to be possible explanation to the inhibition mechanism of P-gp by mPEG-PLA. Taken together, the establishment of a relationship between PLA chain length and impact on P-gp efflux activity and interpretation of action mechanism of mPEG-PLA on P-gp are of fundamental importance and will facilitate future development of mPEG-PLA in the drug delivery area.

Effect of polymers and media type on extending the dissolution of amorphous pioglitazone and inhibiting the recrystallization from a supersaturated state.

Amorphous forms of crystalline drug are widely utilized for bioavailability enhancement of low solubility drugs in the pharmaceutical industry. Polymers have been found to be effective crystallization inhibitors for amorphous forms in solid states during storage or in liquid states during dissolution process. The dissolution and crystallization behaviors of these amorphous forms in the presence or absence of polymers are still far from adequately understood especially in different dissolution environments. The objective of this study was to investigate the effects of polymers and media type on extending the dissolution of amorphous pioglitazone and inhibiting the recrystallization from a supersaturated state. Polyvinylpyrrolidone K30 (PVPK30), polyvinylpyrrolidone K90 (PVPK90), polyethylene glycol 6000 (PEG6000), polyethylene-polypropylene glycol 188 (F-68), hydroxypropylmethylcellulose (HPMC) and beta-cyclodextrin (ß-CD) were employed to understand these behaviors changes because these polymers were used widely. Three solutions including neutral water and phosphate buffer solutions (PBS, pH6.8 and pH7.4) were adopted as dissolution media to determine the behaviors changes comprehensively. In the presence of polymers, dissolution and solubility were extended to different degrees in three media. Polymers can delay the crystallization routes dependently of the medium type. Buffer salts in media reduced the dissolution and accelerated the crystallization process. Crystallization inhibition of these polymers was strongly dependent on the type and pH of media. HPMC displayed the strongest crystallization inhibition effects, resulting in the greatest degree of maintaining a supersaturated state that can sustain most effectively for biologically relevant timeframes.

[Application of microwave irradiation technology to the field of pharmaceutics].

Microwaves can be directly transformed into heat inside materials because of their ability of penetrating into any substance. The degree that materials are heated depends on their dielectric properties. Materials with high dielectric loss are more easily to reach a resonant state by microwaves field, then microwaves can be absorbed efficiently. Microwave irradiation technique with the unique heating mechanisms could induce drug-polymer interaction and change the properties of dissolution. Many benefits such as improving product quality, increasing energy efficiency and reducing times can be obtained by microwaves. This paper summarized characteristics of the microwave irradiation technique, new preparation techniques and formulation process in pharmaceutical industry by microwave irradiation technology. The microwave technology provides a new clue for heating and drying in the field of pharmaceutics.

Construction and immune effect evaluation of the S protein heptad repeat-based nanoparticle vaccine against porcine epidemic diarrhea virus.

Porcine epidemic diarrhea virus (PEDV), a highly virulent enteropathogenic coronavirus, is a significant threat to the pig industry. High frequency mutations in the PEDV genome have limited the effectiveness of current vaccines in providing immune protection. Developing efficient vaccines that can quickly adapt to mutant strains is a challenging but crucial task. In this study, we chose the pivotal protein heptad repeat (HR) responsible for coronavirus entry into host cells, as the vaccine antigen. HR-Fer nanoparticles prepared using ferritin were evaluated them as PEDV vaccine candidates. Nanoparticle vaccines elicited stronger neutralizing antibody responses in mice compared to monomer vaccines. Additionally, HR protein delivered via nanoparticles increased antigen uptake by antigen-presenting cells in vitro by 2.75-fold. The collective results suggest that HR can be used as antigens for vaccines, and the HR vaccine based on ferritin nanoparticles significantly enhances immunogenicity.

Rational design of covalent organic frameworks/NaTaO3 S-scheme heterostructure for enhanced photocatalytic hydrogen evolution.

As a typical perovskite material, NaTaO3 has been regarded as a potential catalyst for photocatalytic hydrogen evolution (PHE) process, due to its excellent photoelectric property and superior chemical stability. However, the photocatalytic activity of pure NaTaO3 was largely restricted by its poor visible-light absorption ability and rapid recombination of photogenerated charge carriers. Therefore, a covalently bonded TpBpy covalent organic framework (COF)/NaTaO3 (TpBpy/NaTaO3) heterostructure was designed and synthesized by the post modification strategy with (3-aminopropyl) triethoxysilane (APTES) and the in situ solvothermal process. Benefiting from the enhanced built-in electric field by the interfacial covalent bonds and the formation of S-scheme heterostructure between TpBpy and NaTaO3, which were proved by the Ar+-cluster depth profile and X-ray photoelectron spectroscopy (XPS), as well as density functional theory (DFT) calculation results, both the charge transfer efficiency and the PHE performance of the TpBpy/NaTaO3 composites were significantly improved. Additionally, the composites exhibited an excellent absorption performance in the visible region, which was also beneficial for the photocatalytic process. As expected, the optimal TpBpy/20%NaTaO3 composite achieved a remarkable hydrogen evolution rate of 17.3 mmol·g-1·h-1 (10 mg of catalyst) under simulated sunlight irradiation, which was about 173 and 2.4 times higher than that of pure NaTaO3 and TpBpy, respectively. This work provided a novel strategy for constructing highly effective and stable semiconductor/COFs heterostructures with strong interfacial interaction for photocatalytic hydrogen evolution.

High-pressure induces topology boosting thermoelectric performance of Bi2Te3.

Decoupling conductivity(σ)and Seebeck coefficient(S)by electronic topological transitions (ETT) under high pressure (2-4 GPa) is a promising method for bismuth telluride (Bi2Te3) to optimize thermoelectric (TE) performance. However, theScannot dramatically increase with increasingσwhen ETT occurs in Bi2Te3, which impedes optimizing TE performance by utilizing ETT in Bi2Te3. A new strategy of enhanced ETT by combining lattice distortions and high pressure is proposed in this work. The lattice distortions in Bi2Te3were introduced by high pressure and high temperature (HPHT) treatment to generate surplus dislocations. Thein-situmeasurements ofσandSat HPHT in Bi2Te3with lattice distortions show an enhanced ETT effect at 2 GPa, which causes decoupleσandSwith an anomalous increase in its|S|about 22%. The ETT effect causes the figure of merit (ZT) of Bi2Te3can be improved to 0.275 at 1.50-2.62 GPa, 460 K, it is more than 62% compared with 0.79 GPa, at 450 K. The excellent TE performance of Bi2Te3arising from the lattice distortions can result in local non-hydrostatic pressure which enhances ETT under high pressure. This work provides a new strategy to enhance ETT to decoupleσandS, and search for better TE materials from the pressure dimension in the future.

Lateral shifts and photon tunneling in a frustrated total internal reflection structure with a negative-zero-positive index metamaterial.

Motivated by the realization of the Dirac point (DP) with a double-cone structure for optical field in the negative-zero-positive index metamaterial (NZPIM), the lateral shift and tunneling time of photon tunneling through a frustrated total internal reflection structure containing a NZPIM barrier are investigated by employing Artman's stationary phase method. Near the DP, the lateral shift can vary from positive to negative and the photon tunneling displays a superluminal dynamic. Because of the Hartman effect, both lateral shift and tunneling time tend to a saturation value when the barrier thickness increases. These results may lead to potential applications in integral optics and optical-based devices and also suggest analogous phenomena of valance electron in single-layered carbon graphene.

[The development of co-amorphous drug systems].

Converting two poorly water-soluble crystalline drugs to co-amorphous drug systems by ball milling, quench-cooling, or cryo-milling method can improve stability of the drug, enhance dissolution rates, and reduce adverse reactions of the single drug. Co-amorphous system has been used to solve problems of co-administration of medicines. Formation and intermolecular interactions of co-amorphous drug systems may be verified by differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Raman spectroscopy (RS) and Fourier transform infrared spectroscopy (FT-IR). Stability of co-amorphous drug systems is influenced by their glass transition temperature (Tg) and intermolecular interactions. The theoretical Tg values and the interaction parameter x are calculated by Gordon-Taylor equation and the Flory-Huggins equation, respectively. Thus, co-amorphous drug systems are analyzed theoretically at molecular level. Co-amorphous drug systems provide a new sight for the co-administration of medicines.