Self-Assembly as a Flexible Route to Multifunctional Nanomaterials

In recent years, a number of single-function nanomaterials (polymer nanoparticles, carbon nanotubes, gold nanoshells, quantum dots, etc.) have been developed for therapeutic and diagnostic applications. The next phase of research aims to construct multicomponent entities which combine several functional properties into an integrated system, permitting more effective therapeutic regimens, earlier and more accurate disease detection and non-invasive assessment of responses to therapies. In this work, a modular technology for the preparation of biocompatible multifunctional nanoparticles using block copolymer directed self-assembly is developed. The technology allows for the integration of materials of diverse physical and chemical properties based solely on thermodynamic driving forces. The key to the process is the balance of times scales for micromixing, self-assembly, flocculation and nucleation/growth. Using this technology, stable and uniform composite nanoparticles (CNPs) simultaneously encapsulating nanocrystals and organic drug molecules are prepared with tunable sizes, high concentrations of encapsulated components and precise control of component compositions, enabling joint applications in drug delivery, medical imaging and diagnostics. The design and preparation of novel CNP constructs based on magnetic nanocrystals for MRI contrast enhancement and on up-converting phosphors for photodynamic therapy of deep tissue cancers will be presented. Finally, methods for selective targeting of CNPs to disease tissues via a synergistic combination of passive (size-directed) and active (ligand-directed) targeting strategies will be discussed. Overall, the technology provides a comprehensive and highly flexible platform for the tailored design and preparation of multifunctional nanomaterials based on economical and scaleable synthetic methods

STUDI TENTANG MOTIVASI BELAJAR SISWA KELAS X TGB PADA MATA PELAJARAN KELOMPOK PRODUKTIF DI SMKN 1 SUMEDANG

Dalam mengikuti pembelajaran mata pelajaran kelompok produktif banyak faktor yang mempengaruhinya, baik faktor dari dalam diri sendiri maupun dari luar. Faktor-faktor tersebut yaitu faktor jasmani, faktor psikologis, faktor lingkungan keluarga, dan faktor lingkungan sekolah. Tujuan dari penelitian ini adalah mengetahui bagaimana gambaran dari setiap faktor tentang motivasi belajar siswa kelas X TGB pada mata pelajaran kelompok produktif dan untuk mengetagui faktor yang paling beasar persentasenya dalam menggambarkan motivasi belajar siswa kelas X TGB pada mata pelajaran kelompok produktif di SMKN 1 Sumedang. Penelitian ini menggunakan metode deskriptif analisis dengan pendekatan kuantitatif. Pengumpulan data dilakukan dengan cara menyebar angket. Jumlah sampel dalam penelitian ini sebanyak 60 orang responden dengan teknik pengambilan sampel yaitu total sampling yang artinya sampel mengambil jumlah semua populasi siswa kelas X jurusan TGB. Hasil penelitian didapat bahwa faktor jasmani, faktor psikologis, faktor lingkungan keluarga, dan faktor lingkungan sekolah dapat dikategorikan berpengaruh terhadap motivasi belajar siswa kelas X jurusan teknik gambar bangunan pada mata pelajaran kelompok produktif di SMKN 1 Sumedang dan faktor paling besar persentasenya dalam menggambarkan motivasi belajar siswa kelas X jurusan teknik gambar bangunan pada mata pelajaran produktif di SMKN 1 Sumedang adalah faktor lingkungan sekolah

Sea Level Variations and their Relations to the Meteorological Factors in the Arab Gulf Area with Stress on Monthly Means

The hydrographic and meteorological conditions affecting the sea level in the Arab Gulf region have been reviewed. The monthly mean sea level data along the Saudi Arabian coast, relative to Indian Spring Low Water (ISLW) and the atmospheric pressure of eight years from 1980 to 1987 have been analysed spectrally. This indicated that the annual cycle is the main oscillation in both the sea level and pressure records. The oscillations with frequency less than 0.2 cycle/month were coherent. The Fourier analysis of six years data of monthly means showed that the annual cycle has an amplitude of 10-11 cm. The monthly mean sea level in the last two years was calculated using the harmonic simulation and the statistical models relating to the sea level and atmospheric pressure. The comparison between the calculated values and the observed ones in 1986 and 1987 showed reasonable agreement; the harmonic simulation deviated from the observations by about + 5 cm. The influence of the factors other than the atmospheric pressure on the sea level of the study area was found to be positive from June to December and negative from January to April or May, with maximum absolute value of about 11 cm, while the statistical models predict only the pressure effect

Evaluation of superalloy heavy-duty grinding based on multivariate tests

The quality and economy of grinding depend on proper selection of grinding conditions for the materials to be ground. In order to evaluate the effect of heavy-duty grinding, a new performance index, which includes specific material removal rate, size accuracy, and grinding forces, was proposed. Robust design of experiment, including orthogonal arrays, the signal-to-noise ratio (SNR) method, and analysis of variance (ANOVA) for multivariate data, was employed to estimate the effect of uniform experimental design and to optimize grinding parameters. Empirical models of grinding force were investigated for finite element analysis of new fixture design. These empirical models, based on robust design of experiments and multiple regression methodology, have been confirmed through further verification experiments. Correlation coefficients from 0.87 to 0.96 were achieved

Planning and control of a hybrid vacuum-forming system based on screw-pin tooling

This paper introduced planning and control of a hybrid vacuum-forming machine system (HAVES). The HAVES was developed to integrate CAD/CAM, screw-pin tooling, CNC, vacuum forming and optical measurement device together to produce vacuum forming components. The screw-pin tooling was employed to replace traditional dedicated solid tooling and its reconfigurability provided the HAVES with advantages in rapid producing small batch and mass customization products. The whole control system of the HAVES is divided into two parts: one for screw-pin tooling adjustment and machining by using CNC control, and the other for vacuum forming by using PLC control. The detail design of the control system was discussed

Storm Surge Generation by Winter Cyclones at Alexandria, Egypt

The storm surges generated by winter cyclones in the Eastern Mediterranean, at Alexandria coast, are classified according to the synoptic situations. The data used are the hourly sea level values in the western harbour of Alexandria, the atmospheric pressure and the wind velocity at a station nearby the tide gauge during storm periods, from 1971 to 1984. Five types of storm surges were identified. Type A represents the weak surge case with a maximum residual of the order of 12-18 cm. Type B has a maximum residual between 20 and 24 cm. Type C is a moderate surge with an average maximum residual (26-30 cm). Type D has a strong surge, between 35 and 38 cm. Finally, type E has the strongest surge, reaching 43 cm. The depression tracks associated with each type are presented and the observed surges are compared with calculated ones using an equation given by Hamed (1983). A reasonable agreement, with a standard deviation ± 5 cm, was found between observations and calculations

A framework to support multiple perspectives in eco-efficiency decisions

Increasingly, it is recognised that human activity is causing our environment to degrade, and that there is a very real danger of doing irreversible damage to natural systems of which we have only a partial understanding. Neither living in, nor doing business in a future world with a degraded environment is desirable, and individuals and businesses alike are increasingly seeking ways to operate on a more sustainable basis. Sustainability was defined by WCED [1] as “meeting the needs of the present without compromising the ability of future generations to meet their own needs” – but how can this aspiration be translated into specific decisions and actions? This paper describes some of the difficulties that must be overcome in the creation of a decision-support framework for eco-efficiency decisions, in order to ensure that we are targeting the right problems