RESUMO
Since the invention of the scanning tunneling microscope (STM), it has been a powerful tool for probing the electronic properties of materials. Typically STM designs capable of obtaining resolution on the atomic scale are limited to a small area which can be probed. We have built an STM capable of coarse motion in two dimensions, the z- and x-directions which are, respectively, parallel and perpendicular to the tip. This allows us to image samples with very high resolution at sites separated by macroscopic distances. This device is a single unit with a compact design making it very stable. It can operate in either a horizontal or vertical configuration and at cryogenic temperatures.
RESUMO
The teaching and research tool called ‘DietPLUS’, developed by the present author at an institution of higher learning in 2007, contains nutrient information of 840 food items in Excel format. DietPLUS functions as a ‘2-in-1’ food composition database plus a rapid calculator of nutrient intakes, with the option of ‘collapsing’ the food composition face leaving only the nutrient calculator face. The macronutrients featured in the programme are energy, protein, fat, carbohydrates, dietary fibre, sugars (intrinsic + added), polyunsatuared omega-6 fatty acids (mainly linoleic acid, LA) and polyunsaturated omega-3 fatty acids [alphalinolenic acid (ALA) or eicosapentaenic acid (EPA) + docosahexaenolic acid (DHA)]. The micronutrients in the programme are vitamin A (as retinol equivalents, RE), vitamin C, thiamin (vitamin B1), riboflavin (vitamin B2), and niacin. Cholesterol content was included to complete the list of food components tabled. Food items consumed are converted into gram quantities (edible portion) and are entered in one column in the Excel programme which emphasises the simplicity and user-friendliness of the present nutrient calculator. DietPLUS instantaneously sums up the macronutrients and micronutrients consumed with each subsequent entry. Macronutrients (protein, fat, carbohydrate, sugars and dietary fibre) consumed are presented as gram quantities and a percentage of the Recommended Nutrient Intakes for Malaysia 2005. An approximate number of servings are also provided for vegetables, fruits, legumes, fish and meat, which may be useful in meal planning and nutrition/dietetic counselling.
