The following propositions are true: (1) For all sets x, y, z such that z ∈ x and z ∈ y holds x \ {z} = y \ {z} iff x = y. (2) For all natural numbers n, k holds k ∈ Seg n iff k−1 is a natural number and k − 1 < n. Let f be a natural-yielding function and let X be a set. One can verify that f↾X is natural-yielding. Let f be a finite-support function and let X be a set. One can check that f↾X is...

The production of plant seedlings has traditionally used polyethylene bags, which are thrown out in the soil or burned after transplant because the large amount of organic material attached to the bags makes recycling difficult. Additionally, when a seedling is taken from the bag for transplant, there is the risk of root damage, which compromises the plant’s development. In this study, we devel...

Nontopological solitons, or “bags,” can arise when fermions acquire their mass through a Yukawa coupling to some scalar field. Bags have played an important role in models of baryons, nuclei, and more recently, in the idea that a Higgs condensate may form around a very heavy top quark. It has been claimed that deep bags, which correspond to tightly-bound states of fermions, will form when the Y...

The major problem in chemotherapy is the targetting of drugs to restricted anatomical sites and specific target cells. Many drugs produce side effects, are toxic to normal tissues and are often prematurely inactivated or excreted. To overcome such difficulties, several forms of drug carriers have been described and tested in animals, and on some occasions in man (Ryman & Tyrrell, 1980; Gregoria...

Background Plastic is convenient, lightweight, unbreakable and relatively inexpensive. However, there are both environmental and health risk from the widespread use of plastics. Bisphenol A, a chemical that mimics the action of the human hormone estrogen, can leach from polycarbonate plastic. Bisphenol A has been found to stimulate prostate cancer cells7 and causes breast tissue changes in mice...

Classical database theory is largely a theory of relations. Relations are sets of tuples in which no duplicate tuples occur. In practice, duplicate elimination is an operation that is considered to be too expensive in many situations. Fundamental classes of integrity constraints interact differently over bags than they do over relations. This holds for keys and functional dependencies, for exam...