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Waste aluminum dross (AD) was used as a substrate on which active constituents were loaded after different activating treatments. A hydrothermal method was applied to synthesize the carbon-aluminum-based composite catalysts (C-ACC), whose pore structures, surface characteristics, and thermal stability were analyzed with the methods of XRF, SEM, and BET. Then, the feasibility of using recycled aluminum dross to catalyze biomass (bits of poplar wood, BPw) pyrolysis to produce hydrogen-rich gas was thoroughly evaluated. The results showed that aluminum dross exhibited significantly enhanced stability after the activating treatments and obtained a relatively large specific surface area and pore volume, presenting similar pore structure characteristics to aluminum oxides (Al 2 O 3). Aluminum dross can be used as an excellent catalyst carrier. Carbon-aluminum-based composite material has a well-developed pore structure. Its specific surface area, average pore size, and pore volume are 118 m2/g, 10.3 nm, and 0.43 cm3/g, respectively, and its heat conductivity coefficient is 0.22 W/m · K. With a combination of advantages of activated carbon and Al 2 O 3 , the properties of iron-loaded carbon-aluminum composite catalysts are superior to those of active constituents and carrier materials. With these catalysts, a relatively high gas yield (43.77%) and a relatively small amount of char deposition (19.79%) have been achieved during the process of catalyzing BPw pyrolysis, with the H 2 yield significantly increased to 64.24mL/g -biomass. So, it provides a new idea for oriented catalyzation of biomass pyrolysis to produce hydrogen-rich gas. Using aluminum dross as a catalyst carrier or a substitute for some part of the carrier can significantly improve the quality of hydrogen-rich gas. A new method of using aluminum dross to obtain catalysts for producing cheap biomass fuel through a pretreatment process has been put forward. • Activated AD achieved a large specific surface area and Al 2 O 3 -like characteristics. • C-ACC combines the advantages of activated carbon and Al 2 O 3. • AD can be applied as an excellent catalyst carrier to produce hydrogen-rich gas. • A new method has been proposed to use AD as a cheap catalyst carrier. • Realizing the new concept of recycling utilization of waste AD and waste biomass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Macro PPBESK beads with hierarchical pores are fabricated via NIPS approach. • PPBESK beads have a good thermal insulation property in a wide temperature window. • The compression modulus of PPBESK beads is more than 50 times higher than PS foam. • The performance can be controlled by the composition of the coagulation bath. Preparation of porous materials from high-performance polymers holds great promise for various advanced engineering applications like thermal insulation. However, it is still a great challenge to fabricate them due to the difficulties in manufacturing them. Herein, a high performance polymer material poly(aryl ether sulfone ketone)s containing phthalazinone and biphenyl moieties (PPBESK) was utilized to fabricate porous materials via a frequently used and simple method named non-solvent induced phase separation (NIPS). Macro porous PPBESK beads have been fabricated in different non-solvent coagulation baths. The kinetics of the phase inversion processes are visualized by the optical microscope. The multi-scale porous structures formed inside the beads endow them an excellent thermal insulation performance in a wide temperature window and a high mechanical performance that the compression modulus is more than 50 times higher than Polystyrene (PS) foam. Therefore, these PPBESK beads provide an optimized combination of functionalities including high mechanical strength and good thermal insulation, which could turn out to be useful in harsh environmental applications. [ABSTRACT FROM AUTHOR]

Global lithium salt price surges drive up costs for high-performance repair materials, creating demand for cost-effective alternatives. Calcium nitrate (CN), with its low production costs and capacity to enhance early cement strength, emerges as a preferred choice. Limited knowledge on combining calcium sulfoaluminate (CSA) cement and CN prompts further exploration for a potentially cost-effective solution in repair materials. This study investigated the impact of varied CN contents on fluidity, setting time, compressive strength, electrical resistivity, heat of hydration, hydration products, and pore structure of CSA cement. The results show that CN can enhanced fluidity, significantly reduced setting time, accelerated hydration process, shortened the hydration induction period, and promoted the nucleation and growth of ettringite. When CN content was 8%, the compressive strength of samples reached its peak at 40.8 MPa, 44.9 MPa, and 47.3 MPa at 3 d, 7 d, and 28 d, respectively. Exceeding 8% CN content will increase the cumulative heat release which reach the maximum of 314.5 J·g−1 at 72 h. The addition of CN will generate the NO 3 -AFm phase and improve the stability of ettringite, as well as refine the pore structure of the samples but increase their total porosity. • The hydration mechanism of CSA cement with high amounts of calcium nitrate (CN) was analyzed. • The optimal amount of CN to enhance the compressive strength of CSA cement samples was 8%. • Although high amounts of CN can refine the pores of CSA cement, it also led to an increase in its total porosity. • The presence of NO 3 -AFm in CSA cement samples affected its hydration process, promoting the stability and formation of AFt. [ABSTRACT FROM AUTHOR]

To explore the economy and substitutability of agricultural waste-based liquid fuel in the whole life cycle, this paper takes ethyl levulinate as the study object, creatively designing the system boundary and establishing the economic analysis model for the preparation of liquid fuel from biomass hydrothermal Liquefaction. Furthermore, the economy of agricultural waste-based ester fuels was analyzed by comprehensively considering dynamic and static indicators. Finally, taking the large-scale system of producing ethyl levulinate, which processes 70,000 t of corn straw per year, as an example, the economic benefit analysis results of hydrolyzing agricultural wastes to produce ethyl levulinate were obtained, and the key factors affecting the production cost were identified and the uncertainty of the production cost was estimated. The physicochemical characteristics and economic analysis of ester-diesel hybrid vehicle fuel were carried out, showing good combustion characteristics and application prospects. This paper can provide theoretical reference and data support for the economic analysis and large-scale application of biomass liquid fuel in the whole life cycle. • The economic analysis model of hydrolyzing agricultural waste to produce ester fuels is developed. • The economic benefits of ethyl levulinate were analyzed by combining the dynamic and static indicators. • The price of ethyl levulinate had the greatest impact on IRR , NPV , and P m. • Key factors affecting and uncertainty of the production cost were estimated. • Mixed fuels of B2.5E2.5 and EL5 have good combustion characteristics and application prospects. [ABSTRACT FROM AUTHOR]

The goal of carbon neutrality provides a new opportunity for the development of renewable energy, especially for wind power. In this paper, 11 regional climate models (RCMs) including CORDEX-EA and PRECIS at two different resolutions are used to evaluate the performance in simulating the spatio-temporal characteristics for wind speed and energy potential from 1981 to 2005. The results show that most models can reproduce the spatio-temporal patterns, and the simulation of the eastern region is better than that of the western region. Besides, most of the higher-resolution models had better simulation performance for spatial-temporal patterns and inter-annual variation. Then, the weighted multi-model ensemble is used to project the changes of the wind speed and the wind power density over China's mainland during the mid-21st century under the RCP8.5 scenario. In future, a decrease in wind speed is projected by most RCMs over China, although some regions, such as the southern parts of China, are projected to have more wind energy potential. The percentage variation of annual mean wind speed will remain in the range of ±4%. The wind power density will decrease in the north and the largest decrease will be found in the northwest. However, the annual mean wind power density in the southeast China will have an increase of 2.21% in the middle of this century. The inter-annual variation of the wind power density in most regions will increase by more than 20%. However, intra-annual variation in the wind power density is likely to decrease in most regions of China, ranging from about −20% to −50%. • A weighted multi-model ensemble was used to project the changes of wind power density over China. • The changes of annual mean wind power density vary in different sub-regions of China, ranging from −3.21% to 2.21%. • The inter-annual variation of the WPD in most regions will increase by more than 20%. [ABSTRACT FROM AUTHOR]

Prostate cancer gene 3 (PCA3) is a non-coding gene specifically overexpressed in prostate cancer (PCa) that has great potential as a clinical biomarker for predicting prostate biopsy outcome. However, genetic determinants of PCA3 expression level remain unknown. To investigate the association between genetic variants and PCA3 mRNA level, a genome-wide association study was conducted in 1371 men of European descent in the REduction by DUtasteride of prostate Cancer Events trial. First-voided urine specimens containing prostate cells were obtained after digital rectal examination. The PROGENSA PCA3 assay was used to determine PCA3 score in the urinary samples. A linear regression model was used to detect the associations between (single nucleotide polymorphisms) SNPs and PCA3 score under an additive genetic model, adjusting for age and population stratification. Two SNPs, rs10993994 in β-microseminoprotein at 10q11.23 and rs10424878 in kallikrein-related peptidase 2 at 19q13.33,were associated with PCA3 score at genome-wide significance level (P = 1.22 x 10-9 and 1.06 x 10-8, respectively). Men carrying the rs10993994 "T" allele or rs10424878 "A" allele had higher PCA3 score compared with men carrying rs10993994 "C" allele or rs10424878 "G" allele (β = 1.25 and 1.24, respectively). This is the first comprehensive search for genetic determinants of PCA3 score. The novel loci identified may provide insight into the molecular mechanisms of PCA3 expression as a potential marker of PCa. [ABSTRACT FROM AUTHOR]

Both genetic and environmental factors are implicated in type 1 diabetes (T1D). Because environmental factors can trigger epigenetic changes, we hypothesized that variations in histone post-translational modifications (PTMs) at the promoter/enhancer regions of T1D susceptible genes may be associated with T1D. We therefore evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy nondiabetic controls, and explored their connections to T1D. We used the chromatin immunoprecipitation-linked to microarray approach to profile key histone PTMs, including H3-lysine 4 trimethylation (H3K4me3), H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac), and H4K16Ac at genes within the T1D susceptible loci in lymphocytes, and H3K4me3, H3K9me2, H3K9Ac, and H4K16Ac at the insulin-dependent diabetes mellitus 1 region in monocytes of T1D patients and healthy controls separately. We screened for potential variations in histone PTMs using computational methods to compare datasets from T1D and controls. Interestingly, we observed marked variations in H3K9Ac levels at the upstream regions of HLA-DRB1 and HLA-DQB1 within the insulin-dependent diabetes mellitus 1 locus in T1D monocytes relative to controls. Additional experiments with THP-1 monocytes demonstrated increased expression of HLA-DRB1 and HLA-DQB1 in response to interferon-γ and TNF-α treatment that were accompanied by changes in H3K9Ac at the same promoter regions as that seen in the patient monocytes. These results suggest that the H3K9Ac status of HLA-DRB1 and HLA-DQB1, two genes highly associated with T1D, may be relevant to their regulation and transcriptional response toward external stimuli. Thus, the promoter/enhancer architecture and chromatin status of key susceptible loci could be important determinants in their functional association to T1D susceptibility. [ABSTRACT FROM AUTHOR]

Abstract: The interferon regulatory factor (IRF) with its 10 members is a very important gene family related to innate immunity. Currently, most fish IRFs reported are from bony fish (teleosts). Cloning and sequencing of IRFs from chondrosteans, the so-called “ancient fish” including sturgeon, paddlefish, bichir and gar, are absent from the literature. In this study, three IRF genes PsIRF-1, PsIRF-2 and PsIRF-5, were cloned and characterized from the paddlefish (Polyodon spathula). PsIRF-1 includes an open reading frame (ORF) of 972bp that encodes a putative protein of 324 amino acids; PsIRF-2 includes an ORF of 1023bp encoding 341 amino acids and PsIRF-5 includes an ORF of 1491bp that encodes 497 amino acids. The PsIRF-5 gene structure is similar to those in mammals but differs from those in teleosts in the first and second exons. Phylogenetic studies of the putative amino acid sequences of PsIRF-1, PsIRF-2 and PsIRF-5 based on the neighbor-joining and Bayesian inference method for Osteichthyes found widely accepted inter-relationships among actinopterygians and tetrapods. Reverse Transcription Polymerase Chain Reaction (RT-PCR) analysis of PsIRF-1, PsIRF-2 and PsIRF-5 in different paddlefish tissues shows higher levels of expression in gill, spleen and head kidney. Poly (I: C) (polyinosinic-polycytidylic acid) stimulation in vivo up-regulated PsIRF-1 and PsIRF-2 expression, while PsIRF-5 gene expression did not respond to the challenge of Poly (I: C). [Copyright &y& Elsevier]

• Three filamentous cyanobacteria strains were selected based on viability in digestate. • The pollutants remove ability from biogas slurry of pig farm was evaluated. • The biochemical composition of algal biomass was examined. • The biodiesel and theoretical biomethane potential of algal biomass were evaluated. • The strain J is the best strain for biogas slurry treat and bioenergy production. The study evaluates 36 filamentous heterocystous cyanobacteria for the treatment of biogas slurry from pig farm and the accumulation of biomass for bioenergy production. The results showed that only the strains B, J, and L were able to adapt to a 10% biogas slurry. The removal rates of ammonia nitrogen, total nitrogen, and total phosphorus for strains J and L were 92.46%–97.97%, 73.79%–79.90%, and 97.14%–98.46%, respectively, higher than that of strain B. Strain J had the highest biomass productivity and lipid productivity. Based on the biodiesel prediction results, it was concluded that strains J and L are more suitable for biodiesel production. The estimation of theoretical methane potential suggests that the algal biomass of strain J also have the desirable possibility of biogas generation. In summary, algal strain J (Nostoc sp.) offers great potential for biogas slurry treatment and for the production of bioenergy. [ABSTRACT FROM AUTHOR]

• Patients with NPC are facing alarming disturbances of anxiety and depression, tailored strategies should be considered for high-risk patients. • Coexisting anxiety and depression commonly occurred and should be attached great importance to. • Central symptoms (sad mood, lack of energy, and trouble relaxing) and bridge symptoms (insomnia) may be potential interventional targets in future clinical practice. To determine the prevalence of anxiety and depression in patients with nasopharyngeal carcinoma (NPC) and to identify central symptoms and bridge symptoms among psychiatric disorders. This cross-sectional study recruited patients with NPC in Guangzhou, China from May 2022, to October 2022. The General Anxiety Disorder-7 (GAD-7) and Patient Health Questionnaire-9 (PHQ-9) were used for screening anxiety and depression, respectively. Network analysis was conducted to evaluate the centrality and connectivity of the symptoms of anxiety, depression, quality of life (QoL) and insomnia. A total of 2806 respondents with complete GAD-7 and PHQ-9 scores out of 3828 were enrolled. The incidence of anxiety in the whole population was 26.5% (depression, 28.5%; either anxiety or depression, 34.8%). Anxiety was highest at caner diagnosis (34.2%), while depression reached a peak at late-stage radiotherapy (48.5%). Both moderate and severe anxiety and depression were exacerbated during radiotherapy. Coexisting anxiety and depression occurred in 58.3% of those with either anxiety or depression. The generated network showed that anxiety and depression symptoms were closely connected; insomnia was strongly connected with QoL. "Sad mood", "Lack of energy", and "Trouble relaxing" were the most important items in the network. Insomnia was the most significant bridge item that connected symptom groups. Patients with NPC are facing alarming disturbances of psychiatric disorders; tailored strategies should be implemented for high-risk patients. Besides, central symptoms (sad mood, lack of energy, and trouble relaxing) and bridge symptoms (insomnia) may be potential interventional targets in future clinical practice. [ABSTRACT FROM AUTHOR]

[Display omitted] • A snap-through bistable hybrid wind energy harvester is proposed. • The hybrid mechanism with a maximized utilization strategy is presented. • The key design parameters to the electrical response are investigated. • Self-powered wind speed measurement and wireless transmission are realized. Real-time monitoring is essential for safeguarding infrastructure in extreme environments, particularly in remote areas with abundant wind resources where sustained strong winds are common. A triboelectric-piezoelectric-electromagnetic hybrid wind energy harvester based on a snap-through bistable mechanism (ST-HWEH) is proposed, which can be used as a sustainable power source and a self-powered wind speed sensor. The piezoelectric energy harvester (PEH), triboelectric nanogenerator (TENG), and electromagnetic energy harvester (EMH) are placed at the maximum strain location, maximum contact area, and maximum displacement position of the bistable buckled beam, respectively, fully utilizing its characteristics in the structural space. The bistable buckled beam undergoes convex and concave snap-through transformations under the magnetic excitation, working synergistically with the buckled boundary to simultaneously achieve the three electromechanical energy conversions, thereby enhancing the electrical output performance of the system. Moreover, both the starting wind speed and resistance torque of the system are effectively reduced through the arrangement of symmetrical excited magnets with antimagnetic poles on the buckled beam. A prototype is prepared and subsequently experimentally verified. The results show that the overall output power density in a composite power generation unit for the ST-HWEH is 83.97 W/m3 at a wind speed of 11 m/s, which is 6.88 times higher than that of the ST-HWEH that only contains TENG. The prototype can easily light up 1000 LED lights at a mild wind speed of 5 m/s and demonstrate self-powered environmental monitoring (taking temperature and wind speed as examples), providing a potential solution for self-powered environmental monitoring and status monitoring of the infrastructure. [ABSTRACT FROM AUTHOR]

Angiotensin II (Ang II)-mediated vascular smooth muscle cell dysfunction plays a critical role in cardiovascular diseases. However, the role of microRNAs (miRNAs) in this process is unclear. We used small RNA deep sequencing to profile Ang II-regulated miRNAs in rat vascular smooth muscle cells (VSMC) and evaluated their role in VSMC dysfunction. Sequencing results revealed several Ang II-responsive miRNAs, and bioinformatics analysis showed that their predicted targets can modulate biological processes relevant to cardiovascular diseases. Further studies with the most highly induced miR-132 and miR-212 cluster (miR-132/212) showed time- and dose-dependent upregulation of miR-132/212 by Ang II through the Ang II Type 1 receptor. We identified phosphatase and tensin homolog (PTEN) as a novel target of miR-132 and demonstrated that miR-132 induces monocyte chemoattractant protein-1 at least in part via PTEN repression in rat VSMC. Moreover, miR-132 overexpression enhanced cyclic AMP-response element- binding protein (CREB) phosphorylation via RASA1 (p120 Ras GTPase-activating protein 1) down-regulation, whereas miR-132 inhibition attenuated Ang II-induced CREB activation. Furthermore, miR-132 up-regulation by Ang II required CREB activation, demonstrating a positive feedback loop. Notably, aortas from Ang II-infused mice displayed similar up-regulation of miR-132/212 and monocyte chemoattractant protein-1, supporting in vivo relevance. In addition, microarray analysis and reverse transcriptasequantitative PCR validation revealed additional novel miR- 132 targets among Ang II-down-regulated genes implicated in cell cycle, motility, and cardiovascular functions. These results suggest that miR132/212 can serve as a novel cellular node to fine-tune and amplify Ang II actions in VSMC. [ABSTRACT FROM AUTHOR]

Few studies have evaluated the long-term relationship between diet quality and cardiometabolic risk factor clustering among children. The moderating effect of socio-economic status (SES) is of interest. To investigate the association between diet quality with cardiometabolic risk among Chinese children and to explore the moderating effect of SES. In this cohort study, 5 waves (1997-2009) of the China Health and Nutrition Survey were used. Diet quality was measured by a modified version of the Chinese Children Dietary Index (mCCDI) based on Dietary Guidelines for Chinese. Children between the ages of 7 and 17 (n = 2903) who completed at least 2 surveys were included. Those who missed measures or had hypertension or diabetes at baseline were excluded. The fasting blood samples were collected in 2009. Waist circumference (WC) and blood pressure (BP) were measured in each survey. A continuous cardiometabolic risk score (MetScore) was derived by a confirmatory factor analysis of 5 components: WC, BP, glucose, triglycerides, and high-density lipoprotein cholesterol. Considering the latency period of the effect of behaviors, the mCCDI was lagged by the period between surveys. Linear regression was used to analyze the association of mCCDI with MetScore and its components. Mixed effect linear regression and lagged mCCDI were used for WC and BP models. Higher mCCDI was independently associated with a lower MetScore at follow-up (β: −.11; 95% CI: −.18 to −.04). Higher lagged mCCDI over time was associated with a lower WC z score overall (β: −.05; 95% CI: −.08 to −.01) and among children in the low SES group (β: −.09; 95% CI: −.14 to −.04) but not those in the high SES group. When examining the 15 mCDDI components separately, scores for 5 components: more grains, vegetables, soybeans and its products; less sugar-sweetened beverages; and more diet variety were significantly associated with a lower MetScore. Among Chinese children, higher diet quality measured by mCCDI was independently associated with a lower MetScore at follow-up. [ABSTRACT FROM AUTHOR]

• A complementary strategy can work as a universal design principle for dual-responsive actuators. • Combining moisture-active/alkane-inert GO with alkane-active/moisture-inert PDMS enables dual-responsive actuation. • GO and PDMS bimorph features fast and reversible response to both moisture and alkane. Smart actuators that enable deforming in a predictable manner under external stimuli have revealed great potential for both traditional and emerging industries. Generally, an asymmetric bilayer structure with one layer active and the other inert to a certain stimulus is essential to realize bending behavior. However, towards the development of dual- or multi-responsive actuators, it still lacks universal and effective strategies for rational design and fabrication of such devices through the simplest way. In this paper, we report a complementary strategy to produce dual-responsive bilayer actuators by combining the moisture-active/alkane-inert graphene oxide (GO) layer with the alkane-active/moisture-inert polydimethylsiloxane (PDMS) layer. The GO@PDMS bimorph actuator can switch its active and inert layers in response to moisture and alkane, respectively, realizing dual-responsive deformation under different actuations. Typical dual-responsive actuators, including a selective air valve and a grip and hook smart claw, are successfully fabricated, demonstrating the capability of effective gases and objects transmission. The complementary bimorph actuator may hold great promise for developing intelligent devices and portable delivery systems. [ABSTRACT FROM AUTHOR]

The combination of surface-enhanced Raman spectroscopy (SERS) technology with microfluidics makes it possible to diagnose genetic disease through label-free on-chip DNA detection. However, open problems including the integration of SERS substrate with microfluidic devices, controllable trapping and releasing of target molecules are still challenging. Here we demonstrate a facile laser scribing method to fabricate silver nanoparticles (AgNPs) and graphene oxide (GO) based biochips as a reusable SERS sensor for DNA detection. Programmable laser scribing of the AgNPs@GO composite film enables direct patterning of sensitive SERS channels that consist of graphene supported AgNPs by exfoliating the composites into hierarchical porous structures. Integrating the SERS-active patterns with a microfluidic chip forms a biochip for allowing SERS detection of DNA. The noncovalent interactions between DNA and graphene mediated controllable trapping and releasing of DNA sequences, enabling efficient on-chip SERS detection and the regeneration of the biochip. The simple, green and cost-effective fabrication of the SERS-active biochips reveals great potential for biomolecular sensing and genetic engineering applications. [ABSTRACT FROM AUTHOR]

In this work, based on density functional theory and quasi-harmonic Debye model, mechanical and thermodynamic properties of orthorhombic Mg2SiO4 under high temperature are predicted. We found out that a-Mg2SiO4 is mechanically stable under the condition from about 0 to 74GPa. Results indicate that the main cause of mechanical instability is high pressure, and the effect caused by high temperature is small. C11, C22, C33, B and vp reduce with temperature just a little and increase with pressure obviously. Mg2SiO4 has excellent resistance to strong compression; however the resistance to shear is unsatisfactory. The Cv tends to the Petit and Dulong limit at high temperature under any pressure, and it is proportional to T³ at extremely low temperature. Pressure has an opposite effect on Cv than temperature. The suppressed effect on Cv caused by pressure is not obvious under low and very high temperature. Mg2SiO4 has three different thermal expansion coefficients (a) along a-, b- and c-axes, and aa

Aberrant expression of EGF receptors has been associated with hormone-refractory and metastatic prostate cancer (PCa). However, the molecular mechanism for EGF signaling in promoting PCa metastasis remains elusive. Using experimental models of PCa metastasis, we demonstrated that EGF could induce robust epithelial-mesenchymal transition (EMT) and increase invasiveness. Interestingly, EGF was found to be capable of promoting protein turnover of epithelial protein lost in neoplasm (EPLIN), a putative suppressor of EMT and tumor metastasis. Mechanistic study revealed that EGF could activate the phosphorylation, ubiquitination, and degradation of EPLIN through an extracellular signal-regulated kinase 1/2 (ERK1/2)-dependent signaling cascade. Pharmacological inhibition of the ERK1/2 pathway effectively antagonized EGF-induced EPLIN degradation. Two serine residues, i.e. serine 362 and serine 604, were identified as putative ERK1/2 phosphorylation sites in human EPLIN, whose point mutation rendered resistance to EGF-induced protein turnover. This study elucidated a novel molecular mechanism for EGF regulation of EMT and invasiveness in PCa cells, indicating that blockade of EGF signaling could be beneficial in preventing and retarding PCa metastasis at early stages. [ABSTRACT FROM AUTHOR]

The preparation, characterization, and in vitro release of aspirin from polymethylmethacrylate (PMMA)/silica composites prepared via a sol–gel route are reported. The in vitro drug release test revealed that the release rate of aspirin in PBS increased with the silica content in the composites; on the contrary, the increase of the content of 3-(trimethoxysilyl) propyl methacrylate (MSMA), a coupling agent, decreased the drug release rate. The drug release rate/composite structure relationship was studied using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and swelling ratio (SR) measurement. The results indicated that the interface between polymer matrix and inorganic fillers has significant influence on the drug release behavior of the composite materials. In addition, models of mass transfer based on Fickian diffusion law at constant temperature and pressure were employed to analyze the results of the in vitro drug release experiments. The drug release behaviors of the composite samples fitted well with the Fickian diffusion model. The values of k, which is in direct proportion to drug release rate, increased with the increasing content of silica while decreased with that of MSMA in the composite samples. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 96:1518–1526, 2007 [ABSTRACT FROM AUTHOR]

The real and imaginary parts of the complex dielectric function were measured by the spectroscopic ellipsometric method in the near-infrared region to study the optical properties of granular FeAg films. On the basis of the Drude model, the purity of Ag films can be optically evaluated. The dependence of the reciprocal relaxation time γ on the Fe concentration of FeAg films was studied, while other conditions were fixed. It was found that γ is linear with the Fe concentration x in the 0