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The University of Waterloo, Waterloo, ON, Canada, is home to North America's first undergraduate program in nanotechnology. As part of the Nanotechnology Engineering degree program, a scanning probe microscopy (SPM)-based laboratory has been developed for students in their fourth year. The one-term laboratory course "Nanoprobing and Lithography" is accompanied by a preceding one-term lecture course, "Nanoprobing and Lithography." The lecture course lays the theoretical foundation for the concepts covered in the laboratory course. The students work in groups of two and obtain hands-on experience in biweekly 3-h laboratory sessions. The labs use a dedicated undergraduate SPM teaching facility consisting of five atomic force microscope stations. The laboratory course covers all common standard modes of operation, as well as force spectroscopy, electrostatic force microscopy, magnetic force microscopy, and scanning probe lithography by electrochemical oxidation and scratching/ploughing of resist. In light of the breadth of the nanotechnology engineering educational program in terms of synthesis and characterization of nanomaterials, the authors designed a dedicated SPM lab with a capacity of up to 130 students per term. (Contains 3 footnotes and 11 figures.)

We employ Monte Carlo simulation in the semi-grand canonical ensemble to obtain the coarse-grained free energy corresponding to an embedded-atom method description of a binary alloy. In particular, the Ginzburg-Landau free energy for a Cu-Ni alloy was determined from a tabulated histogram of the joint probability density of composition, energy, and volume. Using histogram reweighting techniques, the free energy is extrapolated to a range of points in parameter space from a small number of simulations. The results are interpreted by comparing the free energy with that corresponding to a regular solution model of an alloy. In addition, we obtain expressions for thermodynamic quantities in terms of the joint cumulants of the probability density at a given temperature and chemical potential difference. These expressions may then be likewise extrapolated to obtain the dependence of the composition on the temperature and the chemical potential difference over a wide range of parameter space. [ABSTRACT FROM AUTHOR]

Kemasan antistatis digunakan untuk melindungi barang elektronik dari kerusakan fisik, lingkungan, dan terhadap electrostatic discharge (ESD). Conductive Polymer Composites (CPC) merupakan material yang dihasilkan dari penambahan nanopartikel konduktif dengan matriks polimer. Poly lactic acid (PLA) atau dikenal dengan poli asam laktat berpotensi sebagai matriks polimer. Carbon nanotubes (CNT) memiliki konduktivitas listrik yang tinggi dikombinasikan dengan rasio aspek yang besar sehingga kompatibel untuk dijadikan filler CPC. Metode penambahan filler dilakukan dengan melt blending dengan presentase berat filler 0; 0,5; 1; dan 1,5 wt%. Komposit nanomaterial PLA/CNT dikarakterisasi menggunakan uji SEM, FTIR, DSC, dan konduktivitas. Hasil uji SEM dan FTIR menunjukkan bahwa perubahan konsentrasi filler CNT tidak memiliki pengaruh signifikan terhadap morfologi dan struktur CPC. Uji DSC menunjukkan penambahan derajat kristalinitas seiring dengan penambahan konsentrasi CNT. Uji konduktivitas menunjukkan CNT meningkatkan nilai konduktivitas PLA. Nilai konduktivitas PLA menjadi 3,949x10-10 S/cm dan 6,019 x 10-7 S/cm setelah ditambahkan oleh CNT dengan presentase berat sebesar 0,5 wt% dan 1 wt% sehingga memenuhi syarat sebagai kemasan antistatis. Antistatic packaging is used to protect electronic goods from physical damage, the environment, and against electrostatic discharge (ESD). Conductive Polymer Composites (CPC) are materials produced from the addition of conductive nanoparticles with a polymer matrix. Poly lactic acid (PLA) has the potential as a polymer matrix. Carbon nanotubes (CNT) that have high electrical conductivity combined with a large aspect ratio making them compatible to be used as CPC fillers. The method of adding filler was done by melt blending with filler concentrations of 0, 0.5, 1, and 1.5 wt%. PLA/CNT nanomaterial composites were characterized using SEM, FTIR, DSC, and conductivity tests. The results of the SEM and FTIR tests showed that changes in CNT filler concentration did not have a significant effect on the morphology and structure of CPC. DSC test showed an increase in degree of crystallinity along with the addition of CNT concentration. The conductivity test showed that CNT increased the conductivity value of PLA. The conductivity values of PLA become 3.949 x 10-10 S/cm and 6.019 x 10-7 S/cm after being added by CNT of 0.5 wt% and 1 wt% so that they qualify as antistatic packaging.

Listeriosis is a severe infection caused by Listeria monocytogenes. Since 2004, the Centers for Disease Control and Prevention has requested that listeriosis patients be interviewed using a standardized Listeria Initiative (LI) questionnaire. In January 2009, states and the Centers for Disease Control and Prevention began investigating a multistate outbreak of listeriosis among pregnant, Hispanic women. We defined a case as an illness occurring between October 2008 and March 2009 with an L. monocytogenes isolate indistinguishable from the outbreak strain by pulsed-field gel electrophoresis. We conducted a multistate case-control study using controls that were selected from L. monocytogenes illnesses in non-outbreak-related pregnant, Hispanic women that were reported to the LI during 2004 to 2008. Eight cases in five states were identified. Seven of these were pregnant, Hispanic females aged 21 to 43 years, and one was a 3-year-old Hispanic girl, who was excluded from the study. Seven (100%) cases but only 26 (60%) of 43 controls had consumed Mexican-style cheese in the month before illness (odds ratio, 5.89; 95% confidence interval, 1.07 to ∞ P = 0.04). Cultures of asadero cheese made from pasteurized milk collected at a manufacturing facility during routine sampling by the Michigan Department of Agriculture on 23 February 2009 yielded the outbreak strain, leading to a recall of cheeses produced in the plant. Recalled product was traced to stores where at least three of the women had purchased cheese. This investigation highlights the usefulness of routine product sampling for identifying contaminated foods, of pulsed-field gel electrophoresis analysis to detect multistate outbreaks, and of the LI for providing timely exposure information for case-control analyses. Recalls of contaminated cheeses likely prevented additional illnesses. [ABSTRACT FROM AUTHOR]

Objectives: To describe the epidemiology of invasive pneumococcal disease in children under 5 years of age in Far North Queensland and to examine the potential impact of a seven- and 11-valent conjugate pneumococcal vaccine.Methods: A review of all cases of invasive pneumococcal disease in children under 5 years of age in Far North Queensland over a 9 year period (1992-2000). The distribution of the serotypes of isolates causing invasive pneumococcal disease was compared with the serotypes contained in the two vaccines.Results: The annual incidence in indigenous and non-indigenous children under 5 years of age was 163 (95% confidence interval (CI) 122-213) and 42 (95% CI 31-55) cases per 100 000 children, respectively. For children under 2 years of age, these figures were 297 (95% CI 208-411) and 71 (95% CI 49-100), respectively. There was a greater variety of serotypes isolated from indigenous children (n=17) than from non-indigenous children (n=9; P < 0.01). The serotypes within the seven-valent vaccine accounted for 62% (95% CI 46-75%) and 88% (95% CI 76-95%) of the isolates from indigenous and non-indigenous children, respectively (P < 0.01). Serotypes within the 11-valent vaccine accounted for 72% (95% CI 57-84%) of the isolates from indigenous children under 5 years of age, but did not account for any extra isolates from non-indigenous children.Conclusion: Although the seven- and 11-valent conjugate pneumococcal vaccines cover only approximately 60 and 70%, respectively, of the isolates that cause invasive disease in indigenous children in Far North Queensland, they nevertheless have the potential to prevent much morbidity in and hospitalization of these children. It will be essential to maintain surveillance following the introduction of conjugate pneumococcal vaccines so as to monitor changes in the incidence of invasive pneumococcal disease, particularly in high-risk children. [ABSTRACT FROM AUTHOR]

The Australian aluminium industry has played a 'semi-peripheral' role in world production. The transnational corporations dominating the world industry were supplied with large cuantities of cheap raw materials for smelters overseas. Three of the firms also produced metal, largely for local sale. Recently, however, there has been a dramatic restructuring of this pattern with six proposals for smelters producing metal for export. The explanation lies not simply in Australia's energy advantages, but in interactions between the corporate global strategies and Australian governments. New patterns of regional 'comparative advantage' have been created, in part by corporations setting stale governments in competition with one another to provide cheap energy and supportive infrastructure. The impacts of these changes are inherently uneven geographically. [ABSTRACT FROM AUTHOR]