Natural composites exhibit exceptional mechanical performance that often arises from complex fiber arrangements within continuous matrices. Inspired by these natural systems, we developed a rotational 3D printing method that enables spatially controlled orientation of short fibers in polymer matrices solely by varying the nozzle rotation speed relative to the printing speed. Using this method, ...

Sixty % of clones isolated from HeLa cells treated with toxic concentrations of a methylating carcinogen showed increased resistance to the cytotoxicity of N-methyl-N-nitrosourea. D37 values were 6- to 100-fold higher than in the parental cell population. The absence of detectable levels of the repair enzyme O6-methylguanine-DNA methyltransferase indicated that the resistant clones were able to...

Material performance in extreme radiation environments is central to the design of future nuclear reactors. Radiation induces significant damage in the form of dislocation loops and voids in irradiated materials, and continuous radiation often leads to void growth and subsequent void swelling in metals with low stacking fault energy. Here we show that by using in situ heavy ion irradiation in a...

In this paper, we propose four architectures for intrusion-tolerant database systems. While traditional secure database systems rely on prevention controls, an intrusion-tolerant database system can operate through attacks in such a way that the system can continue delivering essential services in the face of attacks. With a focus on attacks by malicious transactions, Architecture I can detect ...

The paper concerns the mechanical performance of continuous fibre/thermosetting polymer matrix composites reinforced in the through-thickness direction with fibrous or metallic rods or threads in order to mitigate against low delamination resistance. Specific illustrations of the effects of microfasteners in reducing delamination crack growth are made for Z-pinned and tufted composites. Respons...

Nature has evolved efficient strategies to synthesize complex mineralized structures that exhibit exceptional damage tolerance. One such example is found in the hypermineralized hammer-like dactyl clubs of the stomatopods, a group of highly aggressive marine crustaceans. The dactyl clubs from one species, Odontodactylus scyllarus, exhibit an impressive set of characteristics adapted for survivi...

Recent strategies to protect system security lay emphasis on designing intrusion-tolerant systems that are able to tolerate intrusions using techniques such as redundancy, diversity, reconfiguration and graceful degradation. These systems are expected to not only detect and tolerate attacks, but also repair, or rejuvenate themselves so as to remove any damage caused by an intrusion. Several res...

this study was conducted to determine drought tolerance genotypes with superiority in different stressed environments. to screening quantitative indices of drought tolerance, genotypes of safflower (carthamus tinctorius l.) were tested in a complete randomized block design with three replications under two different water regimes (irrigated and rainfed). significant positive correlation was fou...

one of the possible ways to ensure future food needs of an increasing world population involves the better water use through the development of crop varieties which need less water and are more tolerant to drought. in order to study the response of twenty landraces of bread wheat to drought stress, an experiment was conducted in a randomized complete block design with three replications under t...