We define the notion of indifferent set with respect to a given class of {0, 1}-sequences. Roughly, for a set A in the class, a set of natural numbers I is indifferent for A with respect to the class if it does not matter how we change A at the positions in I: the new sequence continues to be in the given class. We are especially interested in studying those sets that are indifferent with respe...

The phosphorus activation coefficient (PAC, the ratio of available P to total P) is an important indicator of soil P availability and the transformation of P fractions. Understanding the details of the PAC is useful to estimate soil available P status and to provide P management guidance. In this research, soils from five long-term (23 years) fertilization treatments in three croplands were sel...

Checking copositivity of a matrix is a co-NP-complete problem. This paper studies copositive matrices with certain spectral properties. It shows that an indefinite matrix with exactly one positive eigenvalue is copositive if and only if the matrix is nonnegative. Moreover, it shows that finding out if a matrix with exactly one negative eigenvalue is strictly copositive or not can be formulated ...

We define the notion of indifferent set with respect to a given class of {0, 1}-sequences. Roughly, for a set A in the class, a set of natural numbers I is indifferent for A with respect to the class if it does not matter how we change A at the positions in I: the new sequence continues to be in the given class. We are especially interested in studying those sets that are indifferent with respe...

Protease inhibitors (PI) act by blocking human immunodeficiency virus (HIV) polyprotein processing, but there is no direct quantitative correlation between the degree of impairment of Gag processing and virion infectivity at low PI concentrations. To analyze the consequences of partial processing, virus particles were produced in the presence of limiting PI concentrations or by co-transfection ...

The present work reports the results of a study on the growth kinetics and characterization of matrix polysaccharides in the cell walls of Lygodium japonicum prothallium grown in the presence of copper (Cu). When the prothallium was cultured in the media containing 0.2 mM or 0.4 mM CuSO(4), it showed a rapid accumulation of Cu with a maximum uptake of Cu measured in the cells up to 20 d of cult...

Solar-driven water splitting is a key photochemical reaction that underpins the feasible and sustainable production of solar fuels. An amorphous cobalt-phosphate catalyst (Co-Pi) based on earth-abundant elements has been recently reported to efficiently promote water oxidation to protons and dioxygen, a main bottleneck for the overall process. The structure of this material remains largely unkn...

In this paper, an iterative method is constructed to solve the following constrained linear matrix equations system: [A1(X), A2(X), ∙ ∙ ∙ , Ar (X)] = [E1, E2, ∙ ∙ ∙ , Er ], X ∈ S = {X |X = U (X)}, where Ai is a linear operator from Cm×n onto C pi ×qi , Ei ∈ C pi ×qi , i = 1, 2, ∙ ∙ ∙ , r , and U is a linear self-conjugate involution operator. When the above constrained matrix equations system i...