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π-Conjugated polymers have become qualified candidates for biosensing owing to their unique optoelectronic properties and excellent biocompatibility. In this contribution, nucleotide mismatches in DNA hybridization, being variable in position, are reflected in a stark manner by poly(3-methylthiophene) (P3MT) nanowires (NWs), in which probe DNA sequence is properly functionalized. Selected as the systematic investigation are complementary target DNA (tDNA), random sequence DNA, and three kinds of 1-mer mismatched tDNAs with different mismatch loci away from the NW's surface. Nanoscale optical observation of the single P3MT NWs in solid states reveals that the more distant the mismatch position is from the surface, the higher the photoluminescence (PL) occurs, while the complementary sequence yields the highest but the random one remains the lowest. Hence, the PL intensity increases with the relative length of the DNA-DNA hybridization from the surface. These results deliver a new basis that π-conjugated polymers can be potentially applicable to detailed nucleotide analyses as in single nucleotide polymorphism.

Equity is arguably an agreed upon value within the Computer Science education (CSed) community, and perhaps even more so within efforts to universalize access to CSed within K12 settings through emerging ‘CS for All’ initiatives. However, stakeholders often mean different things when referring to equity, with important implications for what CS teaching and learning looks like in schools. In this paper, we explore the question of how K12 school district actors’ conceptualizations of equity manifest within their planning and implementation of district-wide CSed initiatives. Based on a research-practice partnership aimed at supporting and researching district-wide CSed initiatives, data presented - interviews with district faculty, district planning documents, meeting transcripts and field observations - were drawn from five participating school districts as they made decisions and enacted activities over 11 months in areas including vision-setting, curriculum, professional development, leadership efforts and use of formative data about implementation. Analyzing these data through equity frameworks found in CSed literature, we highlight three distinct but interconnected ways that district actors conceptualized equity within their CSed initiatives: (1) equity in who Computer Science is for, (2) equity in how Computer Science is taught, and (3) equity in what Computer Science is taught. Data show that these varied conceptualizations resulted in different kinds of decisions about CSed in districts. We discuss the implications of these findings in terms of their relevance to equity-oriented CS education researchers, and what lessons they hold for policy-makers and education leaders engaged in their own efforts to support equitable computer science education.

DNA strands have been recently found to play a role in crystallizing organic semiconductors as a substitute for conventional surfactants. Such DNA-guided organic semiconductor particles possessed the recognition ability to complementary target DNAs, resulting in “enhanced luminescence” due to the lesser degree of non-radiative dissipation. Apart from this, in this study we developed selective recognition of mercury ions by utilizing DNA probes having ion-specific thymine-rich motifs. Strikingly, the specific ion–DNA interaction triggered rather distinctive “depressed luminescence” emitting from the particles. The mercury ions were found to be present both at the surface and the inner regions, which were discovered to relate to the drastic morphological distortion of the particles as evidenced by elemental, electron microscopy, and confocal fluorescence microscopy analyses. This novel phenomenon discovered would expand the technological values of organic semiconductors conjugated with oligonucleotides toward a wider range of target-specific applications.

We report a high-speed lateral flow strategy for a fast biosensing with an improved selectivity and binding affinity even under harsh conditions. In this strategy, biosensors were fixed at a location away from the center of a round shape disk, and the disk was rotated to create the lateral flow of a target solution on the biosensors during the sensing measurements. Experimental results using the strategy showed high reaction speeds, high binding affinity, and low nonspecific adsorptions of target molecules to biosensors. Furthermore, binding affinity between target molecules and sensing molecules was enhanced even in harsh conditions such as low pH and low ionic strength conditions. These results show that the strategy can improve the performance of conventional biosensors by generating high-speed lateral flows on a biosensor surface. Therefore, our strategy can be utilized as a simple but powerful tool for versatile bio and medical applications.

Shape-persistent replica synthesis of Au/Ag bimetallic nanoplates is invented. Using a tailored silica cage as a template for the synthesis, a successful shape-replication of Au/Ag bimetallic nanoplate is achieved at the cage core having geometry of initial Ag nanoplate. This work can open up the simple fabrication of multicomponent metallic particles, with nanogeometry being defined early at the initial stage.

A novel protein recognition platform is developed using aptamer-linked polythiophene nanowires. As the aptamer functionalized poly (3-methylthiophene) nanowire is treated by the specific protein, resonance Raman and photoluminescence signals are simultaneously enhanced. Statistical analyses deliver the capability of a single conjugated polymer nanowire with phase-transition characteristics in response to selectivity and concentration.

Guillain-Barré syndrome (GBS) is defined as an acute, autoimmune polyradiculoneuropathy. It is a rare disease that occurs at a rate of 1.11 cases per 100,000 person-years. However, once infected, up to 20% of patients develop severe disability, and approximately 5% die. There have been reports of GBS in different cancers. Among them, there are 6 previous reports of GBS in small cell lung cancer. Here, we report a case of a 52-year-old man who was diagnosed with GBS in the setting of small cell lung cancer with chemotherapy.

• We reviewed serial brain MRIs including DWI and conventional MRI in a patient with MSA-P.

Photocurable formulations containing trifunctional thiol, trifunctional ene, and antibacterial allylimidazolium salts have been employed for transparent antibacterial coatings. The antibacterial component 1-allyl-3-dodecylimidazolium salt (ADIm) is prepared and chemically attached to polymer networks using a one-step thiol–ene photocuring reaction. Ultra-small (USANS) and small angle neutron scattering (SANS) measurements show that the photocured polymers are loosely networked three-dimensional structures with a mass fractal of approximately 2.7 ± 0.2. The minimum inhibitory concentration (MIC) for the ADIm was determined to be 500 μg/ml and 15.63 μg/ml for Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) bacteria, respectively. Coating formulations containing 10 mol% of the antibacterial ADIm photocured on glass substrates showed strong antibacterial activity against environmental bacteria such as E. coli and/or S. aureus.

Immunochromatographic assay (ICA) using nitrocellulose (NC) membrane offers several advantages. This technique is a rapid and straightforward method in contrast to other immunoassays. Polydiacetylene (PDA) vesicles have unique optical properties to show red color and red fluorescence at the same time. In this system, red-phase PDA vesicles are used as a fluorescent dye as well as a surface for immobilized hepatitis B surface antibody (HBsAb). PDA has remarkable stability than other fluorescent dyes. In this study, the most suitable PDA/HBsAb complexes is introduced for detecting hepatitis B surface antigen (HBsAg). Then, the PDA/HBsAb complexes affixed antibody is attached to NC membrane, which has two lines to confirm detection of HBsAg. The main advantage of this system is that the detection of HBsAg can be observed in both visible and fluorescent images due to optical properties of polydiacetylene. Detection of HBsAg is observed up to 0.1 ng/ml by fluorescent analysis and confirmed red line on NC membrane up to 1 ng/ml (HBsAg) by the naked eye. Consequently, these results show that PDA/HBsAb complexes were successfully applied to ICA for the diagnosis of hepatitis B.

We report on the development of raspberry-like silica structures formed by the adsorption of 8-hydroxypyrene-1,3,6-trisulfonate (HPTS)@silica nanoparticles (NPs) on rhodamine B isothiocyanate (RBTIC)@silica NPs for ratiometric fluorescence-based pH sensing. To overcome the well-known problem of dye leaching which occurs during encapsulation of anionic HPTS dye in silica NPs, we utilized a polyelectrolyte-assisted incorporation of the anionic HPTS. The morphological and optical characterization of the as-synthesized dye-doped NPs and the resulting nanohybrids were carried out. The pH-sensitive dye, HPTS, incorporated in the HPTS-doped silica NPs provided a pH-dependent fluorescence response while the RBITC-doped silica provided the reference signal for ratiometric sensing. We evaluated the effectiveness of the nanohybrids for pH sensing; the ratio of the fluorescence emission intensity at 510 nm and 583 nm at excitation wavelengths of 454 nm and 555 nm, respectively. The results showed a dynamic response in the acidic pH range. With this approach, nanohybrids containing different dyes or receptors could be developed for multifunctioning and multiplexing applications.

In this study, silicon nitride (SiNx) thin films were deposited by inductively coupled plasma chemical vapor deposition using trisilylamine (TSA, N(SiH3)3) and ammonia (NH3) plasma, and their moisture barrier properties were improved by plasma post-treatment. Ar, N2, and O2 plasmas were applied to the SiNx films after deposition. After O2 plasma treatment, the reduction of hydrogen in -NHx was confirmed by FT-IR analysis. Mass spectroscopic results showed a distinct hydrogen peak in the O2 plasma processes. Hydrogen was speculated to be removed from the SiNx surface, and the reduced hydrogen on the surface was attributed to the densification of the SiNx thin films. The increased film density reduced the moisture permeability of the SiNx thin films. The water vapor transmission rate (WVTR) of 120-nm thick single SiNx thin films was reduced by 77% to 3.0 × 10−3 g/m2-day from 1.3 × 10−2 g/m2-day with O2 plasma treatment. The increase of WVTR evaluated using a bending test was adopted to estimate flexibility. The increase of WVTR reduced to 71% in O2-plasma treated SiNx single layers from 88% with untreated SiNx single layers after bending the film at a bending radius of 1.5 cm. Multilayer moisture barrier films were fabricated using the O2-plasma treated SiNx layers and hydrocarbon plasma polymer layers made of cyclohexane plasma to further improve the moisture barrier properties and flexibility. The increase of WVTR reduced by approximately five times in the multilayer structure with O2 plasma treated SiNx/hydrocarbon plasma polymer after the bending test. A WVTR of 7.6 × 10−4 g/m2-day was obtained with an alternating nine-layer structure. In this study, we demonstrated that plasma post-treatment processes can improve the moisture barrier properties and flexibility by reducing the hydrogen dangling bonds and hydrogen concentration inside SiNx thin films.

A composite of poly(3,4-ethylendioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and multi-walled carbon nanotubes (MWNTs) was electrochemically polymerized on a fluorine-doped tin oxide (FTO) substrate and used as a photocathode for a dye-sensitized solar cell. The MWNTs were previously O2 plasma treated and simultaneously entrapped while the PEDOT:PSS film was electropolymerized. The resulting plasma-functionalized MWNT-entrapped PEDOT:PSS composite showed enhanced electrocatalytic activity for the reduction of I3− to I−, this was confirmed by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and incident photon-to-current conversion efficiency (IPCE) measurements. An improved energy conversion efficiency by about 13.9% was observed in optimized conditions as compared to a platinized FTO-based photocathode.

This paper describes the development of ScienceKit, a mobile, social media application to promote children's scientific inquiry. We deployed ScienceKit in Kitchen Chemistry (KC), an informal science program where children learn about scientific inquiry through cooking. By iteratively integrating design and implementation, this study highlights the affordances of social media that facilitate children's trajectories of disposition development in science learning. We illuminate how the technological and curricular design decisions made in ScienceKit and KC constrain or expand the types of data we can collect and the actionable insights about learning we can recognize as both educators and researchers. This study offers suggestions for how information gleaned from social media tools can be employed to strengthen our understanding of learning in practice, and help educators better recognize the rich actions that learners undertake, which may be easily overlooked in face-to-face situations.

Energy aware server cluster aims to reduce power consumption at maximum while keeping QoS(quality of service) as much as energy non-aware server cluster. In the existing methods of energy aware server cluster, they calculate the minimum number of active servers needed to handle current user requests and control server power mode in a fixed time interval to make only the needed servers ON. When loads change rapidly, QoS of the existing methods become degraded because they cannot increase the number of active servers so quickly. To solve this QoS problem, we classify load change situations into five types of rapid growth, growth, normal, decline, and rapid decline, and apply five different thresholds respectively in calculating the number of active servers. Also, we use a flexible scheme to adjust the above classification criterion for multi threshold, considering not only load change but also the remaining capacity of servers to handle user requests. We performed experiments with a cluster of 15 servers. A special benchmarking tool called SPECweb was used to generate load patterns with rapid change. Experimental results showed that QoS of the proposed method is improved up to the level of energy non-aware server cluster and power consumption is reduced up to about 50 percent, depending on the load pattern.Keywords:Energy-Aware Server Clusters, Server Power Mode Control, QoS, Multi-Threshold

Two kinds of magnesium hydroxide (Mg(OH)2) rods (Mg-Rod, 150 and 350 nm in size) and plates (Mg-PL, 60 and 300 nm) were prepared, and blended with poly(L-lactide) (PLLA) to obtain PLLA/Mg(OH)2 composites to investigate the effect of the shape and size of Mg(OH)2 particles. The structure, morphology, pH change, thermal and mechanical properties, cytotoxicity, and inflammation of Mg(OH)2 control and PLLA/Mg(OH)2 composites were evaluated. PLLA/Mg-Rod150 (30%) composite showed a 50% higher tensile strength and a 45% improved modulus as compared with PLLA/Mg-PL300 30% composite. Although Mg-Rods displayed similar cell viability (above 80%) as compared to Mg-PLs, the expression levels of TNF-α from Mg-PL60 gradually increased with increasing concentrations from 1 to 300 μg. This indicates that Mg-PL60 had a potential cytotoxicity due to endocytosis. In addition, the byproduct of PLLA/Mg-Rods composite was more effectively neutralized than that of the PLLA/Mg-PLs composite, but cell viability and the expression levels of TNF-α were similar. Therefore, the use of our PLLA/Mg-Rod composite system would be a promising strategy to prevent the current fatal problems in biomedical applications including biodegradable implants such as stents.

Purpose The aim of this study was to identify prognostic factors in stage IVB colorectal cancer in elderly patients, focusing on the influence of treatment modalities, including palliative chemotherapy and primary tumor resection. Methods A cohort of 64 patients aged over 65 years who presented with stage IVB colorectal cancer at the Gangneung Asan Hospital between July 1, 2001, and December 31, 2009, was analyzed. Demographics, tumor location, tumor grade, performance status, levels of carcinoembryonic antigen (CEA), level of aspartate aminotransferase (AST), and distant metastatic site at diagnosis were analyzed. Using the treatment histories, we analyzed the prognostic implications of palliative chemotherapy and surgical resection of the primary tumor retrospectively. Results The cohort consisted of 30 male (46.9%) and 34 female patients (53.1%); the median age was 76.5 years. Primary tumor resection was done on 28 patients (43.8%); 36 patients (56.2%) were categorized in the nonresection group. The median survival times were 12.43 months in the resection group and 3.58 months in the nonresection group (P < 0.001). Gender, level of CEA, level of AST, Eastern Cooperative Oncology Group performance status, tumor location, and presence of liver metastasis also showed significant differences in overall survival. On multivariate analysis, male gender, higher level of CEA, higher AST level, and no primary tumor resection were independent poor prognostic factors. In particular, nonresection of the primary tumor was the most potent/poor prognostic factor in the elderly-patient study group (P = 0.001; 95% confidence interval, 2.33 to 21.99; hazard ratio, 7.16). Conclusion In stage IVB colorectal cancer in elderly patients, resection of the primary tumor may enhance survival.

At around the time that I was invited to write this book review, I enjoyed a leisurely Sunday morning with my daughter Averie, who was 23 months old. We were in our pajamas, snuggling in bed, enjoy...

The detection capability of microresonating sensors is decided by the resonant properties (mass sensitivity and quality factor) because the microresonating sensors have detection principle that the target material of small amount quantitatively detect by measuring the resonant properties change of microresonators. Mass sensitivity is important factor to evaluate minimum detectable mass of microresonating sensors. For the biomolecule detection in liquid, microresonaotrs have to keep the quality factor that can discriminate small frequency change when the liquid sample injected on the microresonating sensors. In order to study mass sensitivity and quality factor of the fabricated microdiaphragm sensors, Pt thin film with different thicknesses are deposited on the our Pb(Zr0.52Ti0.48)O3 layer-embedded microdiaphragm sensors. Increasing the mass sensitivity ranging from 1.68 to 36.61 Hz/ng which is found with the decreasing the width of squared microdiaphragms ranging 900 to 300 μm. The mass sensitivity of our microdiaphragm sensor stands comparison with microcantilever sensor of length scale of 200 ~ 300 μm. Moreover, we find that the quality factor is kept on more than 23 that was ten times better than microcantilever resonating sensor with length scale of 200 μm.

Biodegradable polymers such as poly(L-lactide) (PLLA) have been widely utilized as materials for biomedical applications. However, the relatively poor mechanical properties of PLLA and its acid-induced cell inflammation brought about by the acidic byproducts during biodegradation pose severe problems. In this study, these drawbacks of PLLA are addressed using a stereocomplex structure, where oligo-D-lactide-grafted magnesium hydroxide (MgO-ODLA) is synthesized by grafting d-lactide onto the surface of magnesium hydroxide, which is then blended with a PLLA film. The structure, morphology, pH change, thermal and mechanical properties, in-vitro cytotoxicity, and inflammation effect of the MgO-ODLAs and their PLLA composites are evaluated through various analyses. The PLLA/MgO70-ODLA30 (0-20 wt%) composite with a stereocomplex structure shows a 20% increase in its tensile strength and an improvement in the modulus compared to its oligo-L-lactide (PLLA/MgO70-OLLA30) counterpart. The interfacial interaction parameter of PLLA/MgO70-ODLA30 (5.459) has superior properties to those of PLLA/MgO70-OLLA30 (4.013) and PLLA/Mg(OH)2 (1.774). The cell cytotoxicity and acid-induced inflammatory response are suppressed by the neutralizing effect of the MgO-ODLAs. In addition, the inflammatory problem caused by the rapid acidification of the stereocomplex structure is also addressed. As a result, the stereocomplex structure of the MgO-ODLA/PLLA composite can be used to overcome the problems associated with the biomedical applications of PLLA films.

Background: There has been no previous study on the activity of gemcitabine in combination with oxaliplatin (GemOx) for castration-resistant prostate cancer (CRPC). Methods: The GemOx was preclinically tested for cytotoxic activity in human prostate cancer cell lines. Clinically, patients with CRPC who failed prior docetaxel were treated with gemcitabine 1000 mg m−2 and oxaliplatin 100 mg m−2 intravenously every 2 weeks and prednisolone 5 mg orally twice daily. The primary end point was the prostate-specific antigen (PSA) response rate. Results: The GemOx displayed synergistic effects based on Chou and Talalay analysis. In the phase II study, 33 patients were accrued. The median dose of docetaxel exposure was 518 mg m−2. A total of 270 cycles were administered with a median of eight cycles per patient. A PSA response rate was 55% (95% CI, 38–72) and radiologic response rate was 82% (9 out of 11). With a median follow-up duration of 20.5 months, the median time to PSA progression was 5.8 months (95% CI, 4.4–7.2) and the median overall survival was 17.6 months (95% CI, 12.6–22.6). The most frequently observed grade 3 or 4 toxicities were neutropenia (13%) and thrombocytopenia (13%). Conclusions: The GemOx is active and tolerable in patients with metastatic CRPC after docetaxel failure (NCT 01487720).

BACKGROUND Primary mediastinal large B-cell lymphoma (PMBL) is a distinct subtype of non-Hodgkin lymphoma, which has no consensus for its ideal treatment or prognosis. METHODS We reviewed the clinicopathologic features and clinical outcomes of 25 PMBL cases diagnosed at a single institution between 1993 and 2009 and compared them with 588 cases of non-mediastinal, diffuse large B-cell lymphoma (DLBCL, control group) diagnosed during the same period. RESULTS Thirteen (52.0%) PMBL patients had Ann Arbor stage III or IV disease, and 10 (40.0%) had B symptoms. Thirteen (52%) PMBL patients were classified as high-intermediate/high-risk according to the International Prognostic Index. There was a significant prevalence of young (median: 31 years; range, 15-78 years; P

Purification is critical in any chemical process. The removal of impurities will produce the product in better quality and high standard. In this study, a new type of monomer was prepared by condensation polymerization of alkali lignin (AL) and methacryloyl chloride (MAC). The effect of AL/MAC ratio and the purification of MAC were investigated. The physical and chemical properties of the product obtained which is lignin methacrylate (LMA) were characterized by Fourier Transformed Infrared spectroscopy (FT-IR) and Nuclear Magnetic Resonance (1H-NMR). The result reveals that the purification was successfully removed the hydroxyl groups from the stabilizer in MAC and it is found that all the hydroxyl groups are coming from AL. The single interaction between AL and MAC has successfully enhanced the product obtain which does show no hydroxyl groups. The 1H-NMR data also showed that the purification of MAC influences the outcome. The noise and impurities were eliminated after the purification of MAC, and more pure products were obtained. This new monomer (LMA) synthesis that can be further utilized for various applications.

Twinning boundary-elongated hierarchical Pt nanostructures with excellent electrocatalytic activity were prepared by using axially twinned Pt3Ni nanorods as the platform for epitaxial transfer of a twinned crystal structure. The high electrocatalytic activity of the hierarchical nanostructures results from the synergistic effects of lattice mismatch between the Pt3Ni core and the Pt shell and the elongated twinning boundary.

Introduction: Adenoid cystic carcinoma (ACC) of the breast is a rare condition, and cases in male patients are even less common. Case: We describe a case of ACC of the breast with axillary lymph node metastasis, disseminated osteolytic bone metastasis and bone marrow involvement in a 41-year-old man. Conclusion: Male breast ACC is an extremely rare malignancy; there can be difficulty in obtaining a final diagnosis. We report this case because of its rarity.

The aim of this study was to use immunohistochemistry (IHC) and silver in situ hybridization (SISH) to evaluate alterations in EGFR and HER2 in gastric cancer in order to determine the relationship with prognosis in gastric cancer patients following curative resection.In this study, we analyzed EGFR and HER-2 status by IHC and SISH in 254 stage I-III gastric cancer patients who underwent curative surgery.Thirteen cases (2.48 %) showed EGFR alteration by IHC or SISH. EGFR alteration was associated with older age (P = 0.021), intestinal type (P = 0.040) and higher stage disease (P 0.001). The patients with operable state gastric cancer who had EGFR alteration had an unfavorable prognosis, and multivariate analysis confirmed that EGFR alteration was an independent unfavorable prognostic factor. Twenty-seven cases (10.6 %) showed HER-2 alteration by IHC or SISH. HER-2 alteration was associated with older age (P = 0.006), well or moderately differentiated histology (P 0.001) and intestinal type (P = 0.002).HER-2 alteration is not an independent prognostic factor for curatively resectable gastric cancer. We observed EGFR alteration in a subset of cases with operable state gastric cancer and determined that it was associated with an unfavorable prognosis.

Gastric cancer patients with acute disseminated intravascular coagulation experiences a rare but severe complication resulting in a dismal prognosis. We report a case of advanced gastric cancer complicated with disseminated intravascular coagulation with intractable tumor bleeding which was successfully treated with chemotherapy consisting of 5-fluorouracil and oxaliplatin. The patient was a 63-year-old man who complained of abdominal pain, melena, and dyspnea on 24 November 2010. We diagnosed stage IV gastric cancer complicated by disseminated intravascular coagulation. Gastric tumor bleeding was not controlled after procedures were repeated three times using gastrofiberscopy. With the patient's consent, we selected the 5-fluorouracil and oxaliplatin combination chemotherapy for treatment. After one cycle of 5-fluorouracil and oxaliplatin therapy, symptoms of bleeding improved and the disseminated intravascular coagulation process was successfully controlled. The primary tumor and multiple metastatic bone lesions were remarkably shrunken and metabolically remitted after eight cycles of chemotherapy. In spite of progression, systemic chemotherapy is effective in disease control; further, the patient gained the longest survival time among cases of gastric cancer with disseminated intravascular coagulation.

To better understand who is taking advantage of e-schools and what effects such choices have on achievement, researchers analyzed data from Ohio, which has authorized e-schools since the early 2000s.

The aqueous-phase hydrodeoxygenation (APHDO) of 1-propanol at 230 °C and 35 bar was studied over 1 wt.% Pt catalysts supported on several metal oxides. Pt catalysts supported on amorphous silica, alumina and niobia aerogels, and crystalline niobic acid calcined at 500 °C showed low activities or deactivation. Under the APHDO condition, these supports experienced a structure transformation to crystalline quartz, boehmite and niobia TT phase. Pt/Nb 2 O 5 –Al 2 O 3 aerogel also suffered from the same crystallization behavior. In contrast, Pt/Nb 2 O 5 –SiO 2 aerogels with different Nb/(Nb + Si) ratios maintained a good catalytic performance for prolonged reaction periods. Through characterizations of spent catalysts, Nb 2 O 5 –SiO 2 aerogels were found to retain X-ray amorphous and porous structure. Also, their acid site densities were negligibly changed during the reaction. The catalysts with the Nb / (Nb + Si) ratio of 0.500 and 0.575 reached the molar propane/ethane ratio of about 1.0, indicating that Pt/Nb 2 O 5 –SiO 2 aerogel catalysts are highly active in the presence of water.

In the fructose dehydration to 5-hydroxymethylfurfural (HMF) in dimethyl sulfoxide, the catalytic function of 1,3-dialkylimidazolium-based ionic liquids with different counter-anions was investigated. It was found that the effects of alkyl chain length and additional alkyl group in Cl-containing ionic liquids were negligible whereas the activity of 1-butyl-3-methylimidazolium-based ionic liquids was considerably changed by varying the anion (particularly, halide ions). The latter finding was confirmed by the control experiment result that the addition of KBr or Ca(CH3COO)2 dramatically tuned the catalytic activity of 1-butyl-3-methylimidazolium chloride. From these results and the proposed reaction pathway, it was consequently believed that 1,3-dialkylimidazolium halide contained the dual catalytic function to act as both Bronsted acid and nucleophile for the fructose dehydration to HMF.

Purpose Although most patients with stage I breast cancer have a good prognosis, their clinical outcomes may vary significantly. We assessed clinical outcomes and prognostic factors in stage I breast cancer patients with and without triple-negative breast cancer (TNBC) phenotype. Methods Of 2,489 patients undergoing breast cancer surgery between January 1998 and December 2002, 554 (22.3%) had stage I breast cancer (tumor size ≤2 cm, and lymph node-negative). TNBC was defined as a primary tumor negative for estrogen and progesterone receptors (Allred scores 1 cm (87.2% vs. 75.8%, p=0.028) and received adjuvant chemotherapy (79.5% vs. 44.7%, p

In recent years, many technological interventions have surfaced, such as virtual worlds, games, and digital labs, that aspire to link young people’s interest in media technology and social networks to learning about science, technology, engineering, and math (STEM) areas. Despite the tremendous interest surrounding young people and STEM education, the role of school libraries in these initiatives is rarely examined. In this article, we outline a sociocultural approach to explore how school library programs can play a critical role in STEM education and articulate the need for research that examines the contributions of school libraries as potential hybrid spaces for STEM learning. We propose that school library programs become active participants in STEM learning through the specific roles that school librarians currently play in schools, such as information specialist, instructional partner, and technology ally. We also highlight how these roles can be tailored toward helping young people develop STEM id...

Social network sites (SNSs) like Myspace and Facebook are now popular online communities with large teenage user populations. Teens use these technologies to interact, play, explore, and learn in significant ways. As scholars become interested in studying these new online communities, I contribute to the emerging conversation by re-examining questions about the digital divide. This study utilizes a nationally representative survey from the Pew Internet & American Life Project to investigate whether access and participation divides persist in teens' use of SNSs. I use binary logistic regression to examine the relationship between social, demographic, and technology variables with youth participation in social network sites. The results suggest that traditional divide indicators such as Internet access or parent education are not significant predictors of SNS use. Youth appear to find a way to get connected. Deeper understanding of the social and cultural factors related to participation in social technologies is needed for youth populations.

Many studies on polydiacetylene(PDA) have been investigated to apply to chemical and biological sensors due to their unique optical properties of color change from blue to red and fluorescence change from non-fluorescence to red fluorescence. Especially, high sensitivity against specific molecules is very important to apply polydiacetylenes to various sensors. In this study, we examined the effect of sensitivity enhancement of 10,12-pentacosadynoic acid(PCDA) vesicles in detection α-cyclodextrin(CD) according to control of vesicle size by filters with different pore sizes and poly- merization temperature. Colorimetric response(CR) was calculated using visible spectrometer. In order to investigate the effect of vesicle size on sensitivity of PDA vesicles, two PCDA vesicles were filtered without filtration and with 0.22 µm filter. The two PCDA vesicles were polymerized at 25 o C and were incubated with α-CD(5 mM) for 30 min. The CRs of the former and latter vesicles were 31.4% and 74.0%, respectively. Then, two PCDA vesicles filtered with 0.22 µm filter were polymerized at 25 o C and 5 o C and were reacted with α-CD(5 mM) for 30 min to examine the effect of polymerization temperature. The CRs of the former and latter vesicles were 74.0 and 99.2%, respectively. This sug- gests that vesicle sizes and polymerization temperature are key factors in enhancing the sensitivity of PDA vesicles. In addition, these results are expected to be useful to apply the PDA vesicles as biosensors to detect DNA, protein, and cells.

The switch phenomena of thermochromism of red-phase polymerized PCDA (10,12-pentacosadiynoic acid) Langmuir-Schaefer (LS) films and vesicles were investigated in situ during repeated heating and cooling processes between 25 degrees C and 70 degrees C. During repeated thermal cycles, the solid-supported LS films exhibited switch phenomena in both the visible and fluorescent spectra, that is, the colorimetric response (CR) of the PCDA LS films was ca. 80% at 70 degrees C but is ca. 50-60% at 25 degrees C with an increase of fluorescent intensity in the cooling process and a decrease in the heating process. On the other hand, the PCDA vesicles exhibited such phenomenon only in the fluorescent spectra, that is, the CR of the PCDA vesicles was constant as ca. 100% after being stable red form with the same trend in the fluorescent intensity. The changes in molecular configuration revealed by in situ Fourier transform infrared (FTIR) were in good agreement with the trend of fluorescence emission upon repeated thermal stimuli rather than that of visible absorption.

In this research, we developed a sensor system which can easily detect several chelating agents using polydiacetylene(PDA) vesicles. In comparison to other sensors, PDA based sensor has several advantages. First, detection method is much simpler and faster because it does not require any labeling step in the experiment procedure. Second, significant color-transition from blue to red based upon external stimulus allows us the detection by naked eyes. Finally, it is also possible to perform quantitative analysis of the concentration of the chelating agent by measuring the colorimetric response. In this paper, five types of chelating agents were used, including EDTA, EGTA, NTA, DCTA and DTPA. Among them, EDTA and DCTA triggered especially strong color-transition. In conclusion, this study has led to a successful development of a color transition-based PDA sensor system for easy and rapid detection of chelating agents.

Background Online learning in K-12 education has grown rapidly in the past decade. Cyber charter schools (CCSs) have been a particularly controversial form of online school, but there is very little scholarly examination of these new organizations. As CCSs expand, policymakers and stakeholders have a critical need to understand how to evolve the charter school policies that govern these new school forms. Focus of Study Through a three-site case study, this paper (1) explores what current charter policies govern CCSs and (2) outlines the practices in these schools that might illuminate future policy needs. Specifically, the findings highlight how cyber charters problematize existing charter school policies in the areas of authorizers and governance, teacher policy, and student achievement. Research Design The study presents an exploratory, comparative case study. The exploratory analyses illuminate implications for how policymakers understand governance, teacher policy, and the evaluation of student achievement in cyber charters. The comparative case design also highlights how different state policy contexts might influence the practices of CCSs. Conclusions Cyber charter schools introduce new ways of delivering public schooling. The study shows how state leadership is vital to coordinate student enrollment across geographic boundaries, funding mechanisms, and conflicts between CCSs and established stakeholders. This paper also illuminates how teaching and learning practices differ in an online environment and introduces questions of teacher preparation and professional practices. Finally, CCSs in this study serve unique, niche student populations that opt out of the traditional school system. These considerations are vital for evaluating student achievement in cyber charters.

In this work, silicon nitride (SiNx) films were deposited on plastic substrates at room temperature close to 30[Formula: see text]C on polyethylenenaphthalate (PEN) films in an inductively coupled plasma (ICP) reactor with trisilylamine (TSA, N(SiH[Formula: see text]) precursor and ammonia for flexible moisture barrier films. Moisture barrier property is improved as SiNx layer gets thicker, but cracks are found at thicker films above 300[Formula: see text]nm or more. And the barrier performance of the thicker layers is degraded significantly. In order to improve both flexibility and barrier property, plasma polymer (PP) layers were deposited at room temperature and introduced between the SiNx layers. The water vapor transmission rate (WVTR) of a single SiNx film, [Formula: see text][Formula: see text]g/(m[Formula: see text]), is reduced to [Formula: see text][Formula: see text]g/(m[Formula: see text]) with SiNx/PP/SiNx/PP/SiNx alternating five-layer structure. After 1000 times bending in 1.5[Formula: see text]cm of bending radius, the WVTR increases by 41% with five-layer structure, while that of single-layer structure increases by 69%. This work demonstrated that the SiNx and PP layers can be deposited at room temperature for flexible moisture barrier films.