One-Pot Aqueous Synthesis of Fluorescent Ag-In-Zn-S Quantum Dot/Polymer Bioconjugates for Multiplex Optical Bioimaging of Glioblastoma Cells

Cancer research has experienced astonishing advances recently, but cancer remains a major threat because it is one of the leading causes of death worldwide. Glioblastoma (GBM) is the most malignant brain tumor, where the early diagnosis is vital for longer survival. Thus, this study reports the synthesis of novel water-dispersible ternary AgInS2 (AIS) and quaternary AgInS2-ZnS (ZAIS) fluorescent quantum dots using carboxymethylcellulose (CMC) as ligand for multiplexed bioimaging of malignant glioma cells (U-87 MG). Firstly, AgInS2 core was prepared using a one-pot aqueous synthesis stabilized by CMC at room temperature and physiological pH. Then, an outer layer of ZnS was grown and thermally annealed to improve their optical properties and split the emission range, leading to core-shell alloyed nanostructures. Their physicochemical and optical properties were characterized, demonstrating that luminescent monodispersed AIS and ZAIS QDs were produced with average sizes of 2.2 nm and 4.3 nm, respectively. Moreover, the results evidenced that they were cytocompatible using in vitro cell viability assays towards human embryonic kidney cell line (HEK 293T) and U-87 MG cells. These AIS and ZAIS successfully behaved as fluorescent nanoprobes (red and green, resp.) allowing multiplexed bioimaging and biolabeling of costained glioma cells using confocal microscopy

Advanced Nanocomposite Coatings of Fusion Bonded Epoxy Reinforced with Amino-Functionalized Nanoparticles for Applications in Underwater Oil Pipelines

The performance of fusion-bonded epoxy coatings can be improved through advanced composite coatings reinforced with nanomaterials. Hence, in this study a novel organic-inorganic nanocomposite finish was designed, synthesized, and characterized, achieved by adding γ-aminopropyltriethoxysilane modified silica nanoparticles produced via sol-gel process in epoxy-based powder. After the curing process of the coating reinforced with nanoparticles, the formation of a homogenous novel nanocomposite with the development of interfacial reactions between organic-inorganic and inorganic-inorganic components was observed. These hybrid nanostructures produced better integration between nanoparticles and epoxy matrix and improved mechanical properties that are expected to enhance the overall performance of the system against underwater corrosion

PENGARUH BUKAAN SUDU PENGARAH TERHADAP KERUGIAN HEAD DAN PERFORMANSI TURBIN FRANCIS VERTIKAL

Pembangkit Listrik Tenaga Air masih menjadi tumpuan utama pembangkitan energi listrik di dunia khususnya Indonesia.Data pada tahun 2006 menunjukan bahwa hampir 20% kebutuhan listrik dunia berasal dari PLTA atau sekitar 88% sumber energi terbarukan berasal dari pemanfaatan tenaga air. Ján Andrej Segner mengembangkan turbin air reaksi pada pertengahan tahun 1700. Turbin ini mempunyai sumbu horizontal dan merupakan awal mula dari turbin air modern. Hingga pada tahun 1849, James B. Francis meningkatkan efisiensi turbin reaksi hingga lebih dari 90%. Dia memberikan test yang memuaskan dan mengembangkan metode keteknikan untuk desain turbin air. Turbin Francis dinamakan sesuai dengan namanya, yang merupakan turbin air modern pertama dengan efisiensi lebih dari 90 %.Oleh karena itu dalam pengoperasiannya Turbin Francis harus optimal. Adapun tujuan penelitian ini yaitu membahas pengaruh bukaan sudu pengarah terhadap kerugian head dan performansi Turbin Francis. Kerugian head dihitung menggunakan rumus dan besarnya kerugian head pada instalasi turbin dianalisa dengan menggunakan software Pipe Flow Expert untuk mendapatkan ralat perhitungan. Kemudian dihitung daya dan efisiensi turbin Francis Besarnya nilai kerugian head akan semakin besar seiring dengan bukaan sudu pengarah. Kerugian head terkecil yaitu 0,229 m kemudian akan terus naik hingga bukaan maksimum 195 mm besarnya kerugian head mencapai 20,1375 m. Efisiensi turbin Francis akan terus naik seiring bukaan sudu pengarah akan tetapi pada bukaan 195 mm efisiensi turun pada titik 90,4 %. Sehingga didapat bahwa bukaan sudu pengarah yang menghasilkan efisiensi maksimum yaitu pada bukaan 160, 5 mm yaitu sebesar 98 %

Mechanical Behavior of Nanostructured Hybrids Based on Poly(Vinyl Alcohol)/Bioactive Glass Reinforced with Functionalized Carbon Nanotubes

This study reports the synthesis and characterization of novel tridimensional porous hybrids based on PVA combined with bioactive glass and reinforced by chemically functionalized carbon nanotubes (CNT) for potential use in bone tissue engineering. The functionalization of CNT was performed by introducing carboxylic groups in multiwall nanotubes. This process aimed at enhancing the affinity of CNTs with the water-soluble PVA polymer derived by the hydrogen bonds formed among alcohol (PVA) and carboxylic groups (CNT–COOH). In the sequence, the CNT–COOH (0.25 wt%) were used as the nanostructure modifier for the hybrid system based on PVA associated with the bioactive glass (BaG). The mechanical properties of the nanostructured hybrids reinforced with CNT–COOH were evaluated by axial compression tests, and they were compared to reference hybrid. The averaged yield stresses of macroporous hybrids were (2.3 ± 0.9) and (4.4 ± 1.0) MPa for the reference and the CNT reinforced materials, respectively. Moreover, yield strain and Young's modulus were significantly enhanced by about 30% for the CNT–COOH hybrids. Hence, as far as the mechanical properties are concerned, the results have clearly showed the feasibility of utilizing these new hybrids reinforced with functionalized CNT in repairing cancellous bone tissues

CARACTERIZAÇÃO SISTEMA DE COLAGEM DUPLA-FACE PARA ASSENTAMENTO DE REVESTIMENTO CERÂMICO

Neste estudo foi realizada a caracterização de sistema de colagem dupla-face para assentamento de placas cerâmicas. Foram realizados ensaios de determinação da densidade, dureza, propriedades mecânicas à tração, difração de raios-X, espectroscopia na região do infravermelho e microscopia eletrônica de varredura acoplada com espectroscopia de energia dispersiva. Os resultados obtidos confirmaram algumas informações disponibilizadas pelo fabricante do priduto e permitiram o conhecimento de propriedades que serão importantes na análise do desempenho e durabilidade do mesmo no assentamento de placas cerâmicas de revestimento

Temperature-controlled laminar airflow in severe asthma for exacerbation reduction (The LASER Trial): study protocol for a randomised controlled trial

BackgroundAsthma affects more than 5 million patients in the United Kingdom. Nearly 500,000 of these patients have severe asthma with severe symptoms and frequent exacerbations that are inadequately controlled with available treatments. The burden of severe asthma on the NHS is enormous, accounting for 80 % of the total asthma cost (£1 billion), with frequent exacerbations and expensive medications generating much of this cost.Of those patients with severe asthma, 70 % are sensitised to indoor aeroallergens, and the level of exposure to allergens determines the symptoms; patients exposed to high levels are therefore most at risk of exacerbations and hospital admissions.The LASER trial aims to assess whether a new treatment, temperature controlled laminar airflow (TLA) delivered by the Airsonett™ device, can reduce the frequency of exacerbations in patients with severe allergic asthma by reducing exposure to aeroallergens overnight.MethodsThis multicentre study is a placebo-controlled, blinded, randomised controlled, parallel group trial. A total of 222 patients with a new or current diagnosis of severe allergic asthma will be assigned with a random element in a 1:1 ratio to receive either an active device for one year or a placebo device. The primary outcome is the frequency of severe asthma exacerbations occurring over a 12-month period, defined in accordance with the American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines. Secondary outcomes include changes in asthma control, lung function, asthma-specific and global quality of life for participants and their carers, adherence to intervention, healthcare resource use and costs, and cost-effectiveness. Qualitative interviews will be conducted to elicit participant’s and their partner’s perceptions of the treatment.DiscussionEffective measures of allergen avoidance have, to date, proved elusive. The LASER trial aims to address this. The study will ascertain whether home-based nocturnal TLA usage over a 12-month period can reduce the frequency of exacerbations and improve asthma control and quality of life as compared to placebo, whilst being cost-effective and acceptable to adults with poorly controlled, severe allergic asthma. The results of this study will be widely applicable to the many patients with allergic asthma both in the UK and internationally.Trial registrationCurrent controlled trials ISRCTN46346208 (Date assigned 22 January 2014)

Infarto agudo do miocárdio na cardiomiopatia chagásica crônica: relato de dois casos com coronárias sem lesões obstrutivas

This report describes two patients with chronic Chagas' Heart Disease who developed clinical and laboratorial signs of myocardial infarction. Both patients presented sudden oppressive chest pain, without precipitating factor. In the first case, the highest MB-CK value was 65 IU, 22 hours after the beginning of the pain. On the second case, it was 77 IU at 18 hours after the beginning of the pain. In both cases ECG changes suggesting non-transmural infarction were present. The 99mTc PYP myocardial scintigram of the first case was positive. Coronary angiograms performed on the 18th and 9th day, respectively, after the acute infarction did not display obstructive lesions. Possible mechanisms causing myocardial infarction with normal coronary arteries in Chagas' Disease may include: embolic event's, particularly when there is associated congestive heart failure; coronary thrombosis and coronary spasms.São relatados dois pacientes com doença de Chagas, forma cardíaca crônica, que desenvolveram Infarto Agudo do Miocárdio (IAM). Ambos, apresentaram dor precordial súbita em opressão, sem fatores precipitantes. No primeiro o pico de CKMB foi 65 U após 22 horas do início da dor e no segundo foi de 77U após 18 horas. O ECG em ambos evidenciou apenas alterações sugerindo IAM não transmural. A cintilografia miocárdica com 99mTc-PYP foi positiva no primeiro caso. ¹ coronariografia realizada respectivamente no 16.º e 9.° dia não evidenciou lesões obstrutivas. São discutidos os possíveis mecanismos de IAM com coronárias sem lesões obstrutivas na doença de Chagas tais como: eventos embolíticos, trombóticos e espásticos

Colonização de substrato artificial por macroinvertebrados límnicos, no delta do rio Jacuí (RS, Brasil).

Com a finalidade de avaliar a colonização de um substrato artificial por macroinvertebrados límnicos, foram realizados experimentos em duas estações de coleta no delta do rio Jacuí, em Porto Alegre (RS, Brasil): Canal do Jacuí (CJ) e Cais do Porto (PO). Os substratos foram constituídos de garrafa PET com uma malha interna de nylon. Os organismos que apresentaram os maiores valores de densidade média no substrato artificial exposto no CJ foram L. fortunei (8229,0ind.m-2), Chironomidae (188,9ind.m-2) e Heleobia piscium (39,6ind.m-2) e no PO, L. fortunei (3233,0ind.m-2), Chironomidae (288,9ind.m-2) e Oligochaeta (211,1ind.m-2). Trochospongilla paulula apresentou uma área de cobertura de bioincrustação de 0,016m2, equivalente a 31,1%, da superfície externa do substrato (PET). A esponja de água doce, Trochospongilla paulula, também cresceu sobre as valvas dos mexilhões (epizoísmo). Por meio do teste T de Student foram verificadas diferenças significativas (p=0,01) entre os valores de densidade média de Oligochaeta verificados no CJ (menor valor) e PO (maior valor). Também foram verificadas diferenças altamente significativas (p<0,0001) entre as áreas de bioincrustação de T. paulula verificados no CJ (maior valor) e PO (menor valor). Os valores de densidade média dos demais taxa nos substratos expostos no CJ e PO não diferiram estatisticamente. O substrato foi adequado para amostrar macroinvertebrados, sobretudo poríferos, grupo de difícil amostragem