Aberrant promoter methylation of the CD4 gene in peripheral blood cells of mastitic dairy cows

Bovine mastitis is the most common and costly disease of dairy cattle. Cluster of differentiation 4 (CD4) is closely related to the immune response in mastitis. We quantified promoter CpG methylation levels of the CD4 gene in Chinese Holsteins with clinical mastitis (CM) and in healthy controls; these levels were quantitatively detected with bisulfite pyrosequencing assays and confirmed by cloning sequencing. We found that the bovine CD4 promoter had 16% more methyl groups in the cows with CM (75.0 ± 5.8%) compared to the controls (59.0 ± 8.5%). The decreased expression level of CD4 in CM cows may be downregulated by the increased DNA methylation levels in the CD4 promoter. Two-dimensional hierarchical clustering analyses showed large differences in promoter CD4 methylation between mastitic and healthy cows; the dendrogram clearly distinguished the cows with clinical mastitis from healthy controls based on methylation levels. The DNA methylation level of the CD4 gene was strongly influenced by mastitis status in all comparisons. We suggest that the DNA methylation level of the CD4 promoter can be used as a molecular marker for clinical mastitis in dairy cows.

Antiproliferative Activity of the Chinese Medicinal Compound, Delisheng, Compared With Rg3 and Gemcitabine in HepG2 Cells

Delisheng consists of radix ginseng, radix astragali, venenum bufonis and mylabris. It has been reported that delisheng inhibits the proliferation of adenocarcinoma cells and stimulates their apoptosis. Delisheng can also enhance the body's immunity and induce the redifferentiation of carcinoma cells. Delisheng inhibited the proliferation of HepG2 cells in MTT assay and promoted apoptosis more effectively in contrast to the active components of ginseng extract, Rg3 and gemcitabine. It is possible that Rg3 has an important role in delisheng because they all could regulate the cell cycle, apoptosis and expression of endostatin and VEGFR-2. Delisheng caused the cell cycle to arrest at the S phase, while gemcitabine blocked the cells at the G0/G1 phase in cell cycle analysis. Consequently, the apoptosis rate of the HepG2 cell line can be increased significantly by delisheng in combination with gemcitabine, compared with the single drug. The expression of the procaspase proteins, caspase protein, and dr5 detected by Western blot were increased while bcl-2 and survivin decreased in the delisheng group, compared with controls. The observations suggest that the delisheng induced apoptotic effect might be closely related to the mitochondrial apoptosis pathway, and the death receptor signaling pathway.

Abstract S5-8: Parallel upregulation of Bcl2 and estrogen receptor (ER) expression in HER2+ breast cancer patients treated with neoadjuvant lapatinib

Background: We previously showed in HER2+ models of breast cancer (BC) that potent inhibition of the HER receptor layer can lead to re-expression of estrogen receptor (ER) or activation of the ER pathway. Consequently, the anti-apoptotic ER gene product Bcl2 is upregulated, resulting in enhanced tumor cell survival and treatment resistance. In this study, we investigated whether Bcl2 and ER expression levels are simultaneously increased by neoadjuvant treatment with the dual HER1/2 tyrosine kinase inhibitor lapatinib in HER2+ BC patients.

Methods: In a neoadjuvant phase II clinical trial 49 HER2+ BC patients were treated with lapatinib as a single agent for 6 weeks, followed by trastuzumab/docetaxel for 12 weeks before surgery. Tumor specimens were prospectively collected at different time-points during lapatinib treatment (baseline, and weeks 2 and 4). Bcl2, ER, progesterone receptor (PR), total (t) and phosphorylated (p)-HER2, and Ki67 were assessed by immunohistochemistry. Spearman correlation was used to evaluate the association among the biomarkers at baseline, and the correlation of their changes over time. Fisher's Exact test and non-parametric Wilcoxon rank sum test were used respectively to determine if the frequency and the magnitude of Bcl2 expression changes were associated with baseline ER status.

Results: 35/49 HER2+ tumor specimens (71%) were available for baseline evaluation of Bcl2 and ER. Of those, 12 (34%) were ER-positive (Allred score ≥ 3) and 23 (66%) ER-negative. Baseline Bcl2 expression correlated positively with ER (r = .75; p < .0001) and PR (r = .53; p = .0015), and inversely with t-HER2 (r = −.43; p = .0097). ER baseline expression correlated positively with PR (r = .57; p = .0004), and inversely with t and p-HER2 (r = −.55; p = .0005, and r = −.37; p = .0282, respectively) and Ki67 (r = −.39; p = .0271). Bcl2 changes at week 2 (w2) positively correlated with changes in both ER and PR levels (r = .70; p = .0002 and r = .57; p = .0076, respectively). Additionally, the increase in Bcl2 expression, observed in 9 of the 23 (39%) tumors with tissue available at w2, was significantly more frequent (p = .0147) and of greater magnitude (p = .0001) in ER-pos vs. ER-neg tumors — 8/9 ER-pos tumors at w2 (including 3 converted from ER-neg by lapatinib) had increased Bcl2, while only 1 of the 14 (7%) ER-neg tumors (at baseline and w2) had increased Bcl2. The expression of ER itself at w2 also increased in 3 out of the 6 (50%) tumors which were originally ER-pos and had tissue available at w2, and in all of them Bcl2 increased in parallel. Of note, the single baseline ER-pos tumor that showed a reduction in ER at w2 had a parallel decrease in Bcl2. Similar observations or trends were found at week 4.

Conclusion: Our study suggests that Bcl2 is upregulated as a result of enhanced/restored ER activity upon anti-HER2 therapy with lapatinib in HER2+ tumors. This further supports the use of endocrine along with anti-HER-2 therapy to block this escape pathway which could otherwise cause treatment resistance. In addition, the ER re-expression with lapatinib treatment observed in this study emphasizes the need to re-biopsy HER2+/ER− patients receiving anti-HER2 therapy and to add endocrine therapy if the tumor becomes ER-positive.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S5-8.

Effects of zearalenone on calcium homeostasis of splenic lymphocytes of chickens in vitro

Zearalenone (ZEA) is an estrogenic mycotoxin. It is produced by several Fusarium species and can contaminate food and feed. To investigate the role of calcium homeostasis in ZEA-induced toxicity of poultry and elucidate its cytotoxic mechanism, splenic lymphocytes isolated from chickens were exposed to ZEA (0-25 μg/mL) for 48 h. The intracellular calcium concentration ([Ca2+]i), pH, calmodulin (CaM) mRNA levels, and Na+/K+-ATPase activities and Ca2+-ATPase activities were detected by the fluorescent dyes Fluo-3/AM and BCECF/AM, quantitative real-time PCR, and chromatometry. Supernatant CaM concentrations were simultaneously detected by ELISA. As the ZEA exposure concentration increased, the [Ca2+]i and CaM mRNA levels gradually increased, while intracellular pH, CaM concentrations of supernatants, and intracellular Na+,K+-ATPase and Ca2+-ATPase activities gradually decreased in a dose-dependent manner. There were significant differences (P<0.05 or P<0.01) between the treatment groups and the control group. These results indicate that ZEA cytotoxicity arises by causing an imbalance in calcium homeostasis and intracellular acidification in lymphocytes.

Novel single nucleotide polymorphisms of the bovine methyltransferase 3b gene and their association with meat quality traits in beef cattle

DNA methylation is essential for adipose deposition in mammals. We screened SNPs of the bovine DNA methyltransferase 3b (DNMT3b) gene in Snow Dragon beef, a commercial beef cattle population in China. Nine SNPs were found in the population and three of six novel SNPs were chosen for genotyping and analyzing a possible association with 16 meat quality traits. The frequencies of the alleles and genotypes of the three SNPs in Snow Dragon beef were similar to those in their terminal-paternal breed, Wagyu. Association analysis disclosed that SNP1 was not associated with any of the traits; SNP2 was significantly associated with lean meat color score and chuck short rib score, and SNP3 had a significant effect on dressing percentage and back-fat thickness in the beef population. The individuals with genotype GG for SNP2 had a 25.7% increase in lean meat color score and a 146% increase in chuck short rib score, compared with genotype AA. The cattle with genotype AG for SNP3 had 35.7 and 24% increases in dressing percentage and 28.8 and 29.2% increases in back-fat thickness, compared with genotypes GG and AA, respectively. Genotypic combination analysis revealed significant interactions between SNP1 and SNP2 and between SNP2 and SNP3 for the traits rib-eye area and live weight. We conclude that there is considerable evidence that DNMT3b is a determiner of beef quality traits.

Three-dimensional chemical imaging of embedded nanoparticles using atom probe tomography

Analysis of nanoparticles is often challenging especially when they are embedded in a matrix. Hence, we have used laser-assisted atom probe tomography (APT) to analyze the Au nanoclusters synthesized in situ using ion-beam implantation in a single crystal MgO matrix. APT analysis along with scanning transmission electron microscopy and energy dispersive spectroscopy (STEM-EDX) indicated that the nanoparticles have an average size ~8-12 nm. While it is difficult to analyze the composition of individual nanoparticles using STEM, APT analysis can give three-dimensional compositions of the same. It was shown that the maximum Au concentration in the nanoparticles increases with increasing particle size, with a maximum Au concentration of up to 50%.

Effects of zearalenone on IL-2, IL-6, and IFN-γ mRNA levels in the splenic lymphocytes of chickens

Zearalenone (ZEN) is an estrogenic mycotoxin produced by several Fusarium species, which can contaminate food and feed. These compounds elicit a wide spectrum of toxic effects, including the capacity to alter normal immune function. In this study, the in vitro effects of the treatment of ConA-stimulated splenic lymphocytes with ZEN (0-25 μg/mL) were examined. ZEN modulates the expression of IL-2, IL-6, and IFN-γ. The IL-2 levels were up to fourfold higher (P < 0.05) compared with the levels in the control at toxin concentrations of 25 μg/mL after 48 h of treatment. The IL-6 levels were critically suppressed at this concentration; these changes were very statistically significant (P < 0.05). At lower ZEN concentrations (0.1, 0.4 and 1.6 μg/mL), the IFN-γ levels changed slightly; however at 6.25 and 25 μg/mL, the IFN-γ results reached statistical significance compared with the control levels (P < 0.05). These data suggest that ZEN has potent effects on the expression of chicken splenic lymphocytes cytokines at the mRNA level.

Comparisons between different polychemotherapy regimens for early breast cancer: meta-analyses of long-term outcome among 100,000 women in 123 randomised trials

BACKGROUND

Moderate differences in efficacy between adjuvant chemotherapy regimens for breast cancer are plausible, and could affect treatment choices. We sought any such differences.

METHODS

We undertook individual-patient-data meta-analyses of the randomised trials comparing: any taxane-plus-anthracycline-based regimen versus the same, or more, non-taxane chemotherapy (n=44,000); one anthracycline-based regimen versus another (n=7000) or versus cyclophosphamide, methotrexate, and fluorouracil (CMF; n=18,000); and polychemotherapy versus no chemotherapy (n=32,000). The scheduled dosages of these three drugs and of the anthracyclines doxorubicin (A) and epirubicin (E) were used to define standard CMF, standard 4AC, and CAF and CEF. Log-rank breast cancer mortality rate ratios (RRs) are reported.

FINDINGS

In trials adding four separate cycles of a taxane to a fixed anthracycline-based control regimen, extending treatment duration, breast cancer mortality was reduced (RR 0·86, SE 0·04, two-sided significance [2p]=0·0005). In trials with four such extra cycles of a taxane counterbalanced in controls by extra cycles of other cytotoxic drugs, roughly doubling non-taxane dosage, there was no significant difference (RR 0·94, SE 0·06, 2p=0·33). Trials with CMF-treated controls showed that standard 4AC and standard CMF were equivalent (RR 0·98, SE 0·05, 2p=0·67), but that anthracycline-based regimens with substantially higher cumulative dosage than standard 4AC (eg, CAF or CEF) were superior to standard CMF (RR 0·78, SE 0·06, 2p=0·0004). Trials versus no chemotherapy also suggested greater mortality reductions with CAF (RR 0·64, SE 0·09, 2p<0·0001) than with standard 4AC (RR 0·78, SE 0·09, 2p=0·01) or standard CMF (RR 0·76, SE 0·05, 2p<0·0001). In all meta-analyses involving taxane-based or anthracycline-based regimens, proportional risk reductions were little affected by age, nodal status, tumour diameter or differentiation (moderate or poor; few were well differentiated), oestrogen receptor status, or tamoxifen use. Hence, largely independently of age (up to at least 70 years) or the tumour characteristics currently available to us for the patients selected to be in these trials, some taxane-plus-anthracycline-based or higher-cumulative-dosage anthracycline-based regimens (not requiring stem cells) reduced breast cancer mortality by, on average, about one-third. 10-year overall mortality differences paralleled breast cancer mortality differences, despite taxane, anthracycline, and other toxicities.

INTERPRETATION

10-year gains from a one-third breast cancer mortality reduction depend on absolute risks without chemotherapy (which, for oestrogen-receptor-positive disease, are the risks remaining with appropriate endocrine therapy). Low absolute risk implies low absolute benefit, but information was lacking about tumour gene expression markers or quantitative immunohistochemistry that might help to predict risk, chemosensitivity, or both.

FUNDING

Cancer Research UK; British Heart Foundation; UK Medical Research Council.

A dynamic ventilation model for gravity sewer networks

To implement any effective odour and corrosion control technology in the sewer network, it is imperative that the airflow through gravity sewer airspaces be quantified. This paper presents a full dynamic airflow model for gravity sewer systems. The model, which is developed using the finite element method, is a compressible air transport model. The model has been applied to the North Head Sewerage Ocean Outfall System (NSOOS) and calibrated using the air pressure and airflow data collected during October 2008. Although the calibration is focused on forced ventilation, the model can be applied to natural ventilation as well.

Simulation models of obesity: a review of the literature and implications for research and policy

Simulation models (SMs) combine information from a variety of sources to provide a useful tool for examining how the effects of obesity unfold over time and impact population health. SMs can aid in the understanding of the complex interaction of the drivers of diet and activity and their relation to health outcomes. As emphasized in a recently released report of the Institute or Medicine, SMs can be especially useful for considering the potential impact of an array of policies that will be required to tackle the obesity problem. The purpose of this paper is to present an overview of existing SMs for obesity. First, a background section introduces the different types of models, explains how models are constructed, shows the utility of SMs and discusses their strengths and weaknesses. Using these typologies, we then briefly review extant obesity SMs. We categorize these models according to their focus: health and economic outcomes, trends in obesity as a function of past trends, physiologically based behavioural models, environmental contributors to obesity and policy interventions. Finally, we suggest directions for future research.

Ultrasound-assisted percutaneous catheterization of the axillary vein for totally implantable venous access device

BACKGROUND

Placing a totally implantable venous access device (TIVAD) using the classical subclavian vein puncture method carries the risk of certain complications including hemothorax, pneumothorax and pinch-off syndrome. We set out to determine whether percutaneous axillary vein catheterization can decrease the incidence of these complications.

METHOD

This is a prospective, observational, uni-institutional study. We analyzed the outcome of 113 TIVADs performed by ultrasound-assisted percutaneous axillary vein catheterization from Jun. 2008 to Dec. 2008. Junior residents novice to subclavian and axillary vein catheterization performed the procedures. Insertion and indwelling catheter complications were recorded.

RESULT

In our study population, 100% of TIVAD placements were successful. 27 patients (23.9%) required 3 or more repeated punctures; only one patient (0.9%) had clinically insignificant pneumothorax. Neither arterial puncture nor brachial plexus injury was recorded in our study.

CONCLUSION

Ultrasound-assisted percutaneous axillary vein catheterization for TIVAD is a safe and relatively simple method for inexperienced operators.

Advances in GaAs Mosfet's Using Ga2O3(Gd2O3) as Gate Oxide

In this article, we review the recent progress on GaAs MOSFET's using in-situ MBE-grown Ga2O3(Gd2O3) as the gate dielectric. Both depletion-mode (D-mode) and inversion-mode (I-mode) GaAs MOSFET's with negligible drain current drift and hysteresis are demostrated. The absence of drain current drift and hysteresis indicates that the excellent stability of the oxide and low oxide/GaAs interface state density have been achieved. The drain current density and transconductance are about one order of magnitude higher than the best previous reported data in the literature for an inversion-mode GaAs MOSFET. Excellent high frequency and power performances were also measured from the depletion-mode devices. These improvements are attributed to the excellent Ga2O3(Ga2O3) oxide properties and novel processing techniques.

Stretched inverse opal colloid crystal substrates-induced orientation of fibroblast

Recently, there has been increasing interest in studying the interaction between mammalian cells and nanometer-sized structures. However, the effect of nanostructures on cell behavior, such as cell morphology and alignment, is still largely unknown. Inverse opal colloid crystal substrates, which can be stretched to produce nano-scale pore structures of different degrees of orientation, serve as a convenient model system to study the effect of nanotopography on cell morphology and cell alignment. In this work, we fabricated inverse opal colloidal crystal films that were either unstretched or stretched to three, four or six times their original length, producing pore structures of increasing degree of orientation. Human dermal fibroblast-fetal (HDF-f) cells were seeded and cultured on these four types of substrates. The results from fluorescence microscopy and scanning electron microscopy indicated that cells showed the highest degree of alignment when cultured on inverse opal colloid crystal films that were stretched the most (six times original length). The results also demonstrated that the orientation of nanostructures could affect both the morphology and growth direction of fibroblasts. The ability to control the direction of cell growth through the engineering of nanostructures could have important applications in tissue engineering, especially for tissues with anisotropic structures, such as cardiac muscle, blood vessel, tendon and ligament.

The effects of aging on the strength of surround suppression of receptive field of V1 cells in monkeys

The surround suppression of the receptive field is important for basic visual information processing, such as orientation specificity. To date, the effects of aging on the strength of surround suppression are not clear. To address this issue, we carried out extracellular single-unit studies of the receptive field properties of cells in the primary visual cortex (area V1) in young and old rhesus (Macaca mulatta) monkeys. When presented with the oriented central stimulus, we found that cells in old animals showed reduced orientation and direction selectivity compared with those in young animals. When presented with the oriented central stimulus together with the optimal surround stimulus, more selective cells {orientation bias (OB) >/=0.1; a bias of 0.1 is significant at the P<0.005 level} in animals of both ages showed reduced orientation selectivity compared with the experiment that presented only the oriented central stimulus. When presented with the optimal central stimulus together with the oriented surround stimulus, cells in old animals showed reduced orientation and direction selectivity compared with young animals. Moreover, broadly tuned cells (OB<0.1) in old animals exhibited significantly reduced suppression indices that quantified the strength of the surround suppression of the receptive field, when compared with those in young animals. These results suggest that aging may seriously affect the surround suppression of the receptive field of V1 cells. Thus, the decreased strength of surround suppression of the receptive field may be one possible reason for the decreased stimulus selectivity of V1 cells previously found in the senescent brain. This work will contribute to an understanding of the physiological mechanisms mediating surround suppression of the receptive field.

First Report of Root Rot Caused by Phytophthora sansomeana on Soybean in China

Phytophthora sansomeana E.M. Hansen & Reeser is a newly described species and infects Douglas-fir, alfalfa, and soybean (1). Soybean production is an important part of the local economy in Yili State in Xinjiang Uygur Autonomous Region, northwest China. Unfortunately since 2005, root and stem rot disease has emerged on a number of farms. To identify the causal agent, plant samples with symptoms, including whole plant wilting or yellowing and stunting, were collected from fields during 2005 and 2008. Tissue from the edges of stem lesions was placed on selective lima bean agar (LBA) at 20°C for 3 to 4 days (2,3). Four single zoospore isolates of Phytophthora were obtained and maintained on LBA or 10% V8 juice liquid medium for examination of morphological and physiological characteristics. The colonies on LBA were aerial and rosaceous. The isolates were homothallic, and oogonia and oospores were readily produced in culture after 7 days on LBA plates. Oogonia averaged 38 μm and oospore width ranged from 23 to 48 μm and averaged 31 μm. Antheridia were approximately 15 × 12 μm and predominantly amphigynous in V8 juice. Sporangia were terminal or paragynous on persistent sporangiophores, nonpapillate, ovoid to obpyriform, and measured 52 × 35 μm with an average length/breadth ratio of 1.5. Hyphal swellings were produced in V8 juice 2 days after inoculation. The optimum temperature for growth was approximately 25°C and none occurred at 0 or 35°C. The internal transcribed spacer (ITS) sequence of this Phytophthora species (GenBank FJ966880) agreed 100% with sequences of P. sansomeana isolates deposited in GenBank (GQ853880 and EU925375). Pathogenicity tests were performed by hypocotyl inoculation method (2) using isolate Yili71 and potted soybean cv. Williams. Plants were grown in a growth chamber for 10 days before inoculation in 16-cm-diameter pots (2). Plants were inoculated with 2- × 2-mm plugs of mycelium grown for 4 days on LBA at 25°C, the plugs were adhered to the sides of wounded lower hypocotyls. As controls, plants were inoculated with LBA agar plugs without mycelium (2). Inoculated plants were maintained in a growth chamber at approximately 25°C with a 10-h dark/14-h light cycle and 50% relative humidity and symptom development was monitored daily for 1 week. Wounded stems inoculated with mycelium developed water-soaked lesions, which were similar to those seen on naturally infected plants. A Phytophthora sp. was reisolated from the margins of expanding lesions on wounded stems. To our knowledge, this is the first report of P. sansomeana infection of soybean in China and the threat it may pose to soybean production is unclear. References: (1) E. M. Hansen et al. Mycologia 101:129. 2009. (2) Z. Y. Wang et al. Fungal Genet. Biol. 43:826, 2006. (3) X. B. Zheng. Methods in Phytophthora. Chinese Agriculture Press. Beijing, China, 1995.

Compact optical curvature sensor with a flexible microdisk laser on a polymer substrate

We demonstrate a chip-scale compact optical curvature sensor. It consists of a low threshold InGaAsP microdisk laser on a flexible polydimethylsiloxane polymer substrate. The curvature dependence of lasing wavelength was characterized by bending the cavity at different bending radii. The measurements showed that the lasing wavelength decreases monotonously with an increasing bending curvature. A good agreement between experiment and three-dimensional finite-difference time-domain simulation was also obtained. The sensitivity of the compact device to the bending curvature is -23.7 nm/mm from the experiment.

Molecular dynamics simulation of complex particles in three dimensions and the study of friction due to nonconvexity

We investigate the macroscopic properties of frictionless nonconvex particles using molecular dynamics. The calculations are based on a simple and efficient method to simulate complex-shaped interacting bodies. The particle shape is represented by Minkowski operators. A multicontact time-continuous interaction between bodies is derived using simple concepts of computational geometry. Three-dimensional simulations of hopper flow show that the nonconvexity of the particles strongly affects the jamming on granular flow. Also the model allows the representation of complex bodies with rough surfaces as in friction studies and the reproduction of a wide range of friction and dilatancy angles as in true triaxial tests.

Efficacy and Safety of Valsartan/Hydrochlorothiazide Fixed-dose Combination Compared with Amlodipine Monotherapy as First-line Therapy for Mild to Moderate Hypertension

This double-blind, active- and randomized-controlled study compared the efficacy and safety of a fixed-dose combination of valsartan/hydrochlorothiazide 80 mg/12.5 mg once daily ( n = 32) with amlodipine monotherapy 5 mg once daily ( n = 33) for 8 weeks in patients with mild to moderate hypertension. Non-inferiority of valsartan/hydrochlorothiazide to amlodipine was demonstrated by comparable reductions in sitting systolic blood pressure (SBP), sitting diastolic blood pressure (DBP), and daytime, night-time and 24-h SBP and DBP on ambulatory blood pressure monitoring. Between-group comparisons of adverse events and changes in laboratory parameters did not reach statistical significance, except for uric acid which showed a significant increase in the valsartan/hydrochlorothiazide group compared with the amlodipine group, but was still below the laboratory's upper limit of normal. In conclusion, the use of the fixed-dose combination of valsartan/hydrochlorothiazide 80 mg/12.5 mg once daily as a starting regimen in patients with mild to moderate hypertension was shown to have non-inferior efficacy and comparable safety for daily practice compared with amlodipine 5 mg once daily monotherapy.

Dielectric constants of multiwall carbon nanotubes from direct current to microwave frequencies

A cylindrical rod constructed from a uniform mixture of multiwall carbon nanotubes and alumina powders dissolved in paraffin was inserted in the center of a radio frequency cavity. The real and imaginary dielectric constants of carbon tubes at various frequencies were measured, respectively, from the resonant frequencies and the quality factors, by a resistance-inductance-cacitance (RLC) meter and a microwave network analyzer. The dielectric rod benefits the protection of the sample from adsorbing moisture and preventing the rod from filling with air, thus making accurate measurments. A tunable probe specifically designed for the field pattern of a TM010 mode is delineated to improve the microwave coupling of the dielectric microwave resonator. This refined design is expected to facilitate the measurement yielding a significant manner. The real and imaginary parts of the dielectric constant of carbon nanotubes increase and decrease, respectively as frequencies increase satisfactorily in complying with the description from the free electron Drude model.

Recycle of Alum recovered from water treatment sludge in chemically enhanced primary treatment

An investigation was made to study the feasibility of recovering the Alum from coagulation sludges and reusing it in chemically enhanced primary treatment (CEPT) process to make the CEPT more cost-effective and recover the resource (Alum) efficiently. The optimum condition and efficiency of the acidification method for Alum recovery from coagulation sludge were investigated in the test. The results show that when the recovery rate of Alum reaches its highest level, 84.5%, the reduction rate of sludge is 35.5%. It turns out that the capability of recovered coagulant to remove turbidity, UV(254) and COD are 96%, 46% and 53%, respectively. The results prove that the recovered coagulants could be used in CEPT and the efficiency of recovered coagulant to remove pollutants is similar to that of fresh coagulant. Although some substances will be enriched during recycle, they have little effect on the quality of treated wastewater. The experiments verify that it would be an advisable and cost-effective way to recover Alum from coagulation sludges in water treatment and chemical wastewater treatment, and it could be then recycled to CEPT as well as reduce sludge volume.

Flexible compact microdisk lasers on a polydimethylsiloxane (PDMS) substrate

Compact microdisk cavities were fabricated on a polydimethylsiloxane substrate. The lasing of the flexible compact cavity was achieved with a low threshold power. The whispering-gallery mode of the microdisk was also characterized with three-dimensional finite-difference time-domain simulation. The curvature dependence in output power and threshold was also demonstrated by bending the microdisk cavity.

Effects of alginate coated on PLGA microspheres for delivery tetracycline hydrochloride to periodontal pockets

The effects of alginate coated on tetracycline (Tc) loaded poly (D, L-lactic-co-glycolic acid) (PLGA) microspheres fabricated by double emulsion solvent evaporation technique for local delivery to periodontal pocket were investigated. Alginate coated PLGA microspheres showed smoother surface but enlarged their particle sizes compared with those of uncoated ones. In addition, alginate coated microspheres enhanced Tc encapsulation efficiency (E.E.) from 11.5 +/- 0.5% of uncoated ones to 17.9 +/- 0.5%. Moreover, all of the coated PLGA microspheres even fabricated at different conditions could prolong Tc release from 9-12 days with 50% or higher in cumulative release of Tc compared with those of uncoated ones. The swelling ratios of PLGA microspheres for alginate coated or uncoated ones, one of the possible mechanisms for enhancing Tc release for the coated ones, were measured. The results showed that 20% or higher in swelling ratio for the coated microspheres at the earlier stage of hydration (e.g. < or = 24 h) could be an important factor to result in high Tc release compared to the uncoated ones. In conclusion, alginate coated Tc loaded PLGA microspheres could enhance Tc delivery to periodontal pocket by enhancing drug encapsulated efficiency, released quantities and sustained release period compared with uncoated ones.