The high manufacturing cost for metallic glasses hampers actual commercial applications of this class of fascinating materials. In this letter, the effect of oxygen impurity on the glass forming ability and tensile properties of Zr-BMG composites were studied. Our results have demonstrated that oxygen was absorbed and concentrated only in the precipitated β-Zr phase, leading that the remainder ...

MetPreg, a composite developed by Touchstone Research Laboratories (Tridelphia, WV), is an aluminum metal matrix composite reinforced by continuous Nextel 610 alumina fibers. The question is, after processing, are the Nextel fibers affected in any way that their strengthening contribution to the composite is reduced? From experimentation and statistical analysis, a strength distribution of pre-...

In pursuit of lightweighting of automobiles and low emission of transportation, the efforts to develop high-strength, heat-resistant and fatigue-resistant Al alloys and/or composites have been ongoing. Here we report a novel Al matrix composite with ultrahigh strength reinforced by a three dimensional network of nano-AlN particles for the first time. The in-situ synthesized AlN particles are co...

Laser shock processing (LSP) is an innovative surface treatment technique with high peak power, short pulse, and cold hardening for strengthening metal materials. LSP is based on the application of a high intensity pulsed laser beam (I > 1 GW/cm(2); t < 50 ns) at the interface between the metallic target and the surrounding medium (a transparent confining material, normally water) forcing a sud...

Research demonstrates a positive effect of aerobic exercise on cognitive functioning in older adults. Unfortunately, aerobic exercise is often contraindicated for older adults due to cardiovascular and functional limitations. Low-intensity strengthening exercise may offer a practical alternative, but the neuropsychological benefits and potential neurophysiological mechanisms are less well under...

OBJECTIVE To compare the efficacy of posterolateral hip muscle strengthening versus quadriceps strengthening in reducing pain and improving health status in persons with patellofemoral pain (PFP). DESIGN Comparative control trial. SETTING Rehabilitation facility. PARTICIPANTS Persons with a diagnosis of PFP (N=36; 18 men, 18 women). INTERVENTIONS Patients were alternately assigned to a ...

This paper takes a closer look at behavioral subtyping in the context of concurrency, by considering an example of subtyping of a concurrent datastructure taken from sensor networks. Akin to the extension of a state-machine, this example illustrates conflicts caused by the interference of concurrency and inheritance. In short, the extension consists in declaring additional fields in a subclass,...

We introduce a natural strengthening of prompt simplicity which we call strong promptness, and study its relationship with existing lowness classes. This notion provides a ≤wtt version of superlow cuppability. We show that every strongly prompt c.e. set is superlow cuppable. Unfortunately, strong promptness is not a Turing degree notion, and so cannot characterize the sets which are superlow cu...

The number of bits in a cryptographic one-way hash value is usually selected so that brute-force search for a second pre-image is impossible. Sometimes, application requirements force one to use shorter and, thus, weaker hash values. Over years, increases in the attacker’s computational capacity will render any protocol that depends on such hashes insecure. In this paper, we present a simple te...

It is increasingly recognized that stronger health systems are needed to deliver health care interventions at the scale necessary to achieve and sustain healthrelated Millennium Development Goals (MDGs), especially in Africa (1, 2). This is evident in the growing willingness of two of the largest global health initiatives, the Global Fund to Fight AIDS, Tuberculosis and Malaria, and the Global ...