Thermomechanical relaxation and different water states in cottonseed protein derived bioplastics

Thermomechanical relaxation events and different water states in cottonseed protein bioplastics are presented whilst investigating the effects of aldehyde cross-linking agents. Thermomechanical relaxation of cottonseed protein bioplastics associated with protein denaturation, moisture absorption and broad glass transitions (Tg) were observed from DSC and DMA measurements. It was shown that variation of the aldehyde influences the storage modulus at very low temperature (below Tg). From measurements of the water fusion point, enthalpy, vaporisation, and weight loss, three water states in the water-absorbed bioplastics are suggested; namely strongly-bound-to-polymer, weakly-bound-to-polymer and bulk-like water. The water content and unreacted cross-linking agents are influential factors in controlling formation of the different water states, whilst the selection of different aldehydes was found to be negligible. These results could be valuable for adjusting the thermomechanical relaxations of protein based bioplastics, and tailoring their properties in wet environments

The tight skin mouse: demonstration of mutant fibrillin-1 production and assembly into abnormal microfibrils

Mice carrying the Tight skin (Tsk) mutation harbor a genomic duplication within the fibrillin-1 (Fbn 1) gene that results in a larger than normal in-frame Fbn 1 transcript. In this study, the consequences of the Tsk mutation for fibrillin-containing microfibrils have been examined. Dermal fibroblasts from Tsk/+ mice synthesized and secreted both normal fibrillin (approximately 330 kD) and the mutant oversized Tsk fibrillin-1 (approximately 450 kD) in comparable amounts, and Tsk fibrillin-1 was stably incorporated into cell layers. Immunohistochemical and ultrastructural analyses of normal and Tsk/+ mouse skin highlighted differences in the gross organization and distribution of microfibrillar arrays. Rotary shadowing of high Mr preparations from Tsk/+ skin demonstrated the presence of abundant beaded microfibrils. Some of these had normal morphology and periodicity, but others were distinguished by diffuse interbeads, longer periodicity, and tendency to aggregate. The presence of a structurally abnormal population of microfibrils in Tsk/+ skin was unequivocally demonstrated after calcium chelation and in denaturating conditions. Scanning transmission electron microscopy highlighted the presence of more mass in Tsk/+ skin microfibrils than in normal mice skin microfibrils. These data indicate that Tsk fibrillin-1 polymerizes and becomes incorporated into a discrete population of beaded microfibrils with altered molecular organization

COSMOS: the COsmic-ray Soil Moisture Observing System

The newly-developed cosmic-ray method for measuring area-average soil moisture at the hectometer horizontal scale is being implemented in the COsmic-ray Soil Moisture Observing System (or the COSMOS). The stationary cosmic-ray soil moisture probe measures the neutrons that are generated by cosmic rays within air and soil and other materials, moderated by mainly hydrogen atoms located primarily in soil water, and emitted to the atmosphere where they mix instantaneously at a scale of hundreds of meters and whose density is inversely correlated with soil moisture. The COSMOS has already deployed more than 50 of the eventual 500 cosmic-ray probes, distributed mainly in the USA, each generating a time series of average soil moisture over its horizontal footprint, with similar networks coming into existence around the world. This paper is written to serve a community need to better understand this novel method and the COSMOS project. We describe the cosmic-ray soil moisture measurement method, the instrument and its calibration, the design, data processing and dissemination used in the COSMOS project, and give example time series of soil moisture obtained from COSMOS probes

Results of the First Coincident Observations by Two Laser-Interferometric Gravitational Wave Detectors

We report an upper bound on the strain amplitude of gravitational wave bursts in a waveband from around 800Hz to 1.25kHz. In an effective coincident observing period of 62 hours, the prototype laser interferometric gravitational wave detectors of the University of Glasgow and Max Planck Institute for Quantum Optics, have set a limit of 4.9E-16, averaging over wave polarizations and incident directions. This is roughly a factor of 2 worse than the theoretical best limit that the detectors could have set, the excess being due to unmodelled non-Gaussian noise. The experiment has demonstrated the viability of the kind of observations planned for the large-scale interferometers that should be on-line in a few years time.Comment: 11 pages, 2 postscript figure

A Rapid Photopatterning Method for Selective Plating of 2D and 3D Microcircuitry on Polyetherimide

In this work, a method for the rapid synthesis of metallic microtracks on polyetherimide is presented. The method relies on the photosynthesis of silver nanoparticles on the surface of the polymer substrates from photosensitive silver chloride (AgCl), which is synthesized directly on the polyetherimide surface. The study reveals that the use of AgCl as a photosensitive intermediate accelerates the reactions leading to the formation of silver nanoparticles by up to two orders of magnitude faster than other photodecomposition schemes. The patterning can be conducted under blue light, with notable advantages over UV exposure. Polymers of significant interest to the microelectronics and 3D printing industries can be directly patterned by light using this photography-inspired technique at throughputs high enough to be commercially advantageous. Light exposures as short as a few seconds are sufficient to allow the direct metallization of the illuminated polyetherimide surface. The results show that the silver required for the seed layer is minimal, and the later copper electroless plating results in the selective growth of conductive tracks for circuitry on the light-patterned areas, both on flexible films and 3D printed surfaces

Antimicrobial susceptibilities of Clostridium difficile.

The antimicrobial susceptibilities of 78 strains of Clostridium difficile isolated from patients with and without gastrointestinal symptoms were determined and compared. Strains from patients with symptoms were more likely to show resistance to antibiotics. The antimicrobial susceptibilities of toxigenic and non-toxigenic strains were found to be similar

Wall-thickness-dependent strength of nanotubular ZnO

We fabricate nanotubular ZnO with wall thickness of 45, 92, 123 nm using nanoporous gold (np-Au) with ligament diameter at necks of 1.43 mu m as sacrificial template. Through micro-tensile and micro-compressive testing of nanotubular ZnO structures, we find that the exponent m in (sigma) over bar proportional to (rho) over bar (m), where (sigma) over bar is the relative strength and (rho) over bar is the relative density, for tension is 1.09 and for compression is 0.63. Both exponents are lower than the value of 1.5 in the Gibson-Ashby model that describes the relation between relative strength and relative density where the strength of constituent material is independent of external size, which indicates that strength of constituent ZnO increases as wall thickness decreases. We find, based on hole-nanoindentation and glazing incidence X-ray diffraction, that this wall-thickness-dependent strength of nanotubular ZnO is not caused by strengthening of constituent ZnO by size reduction at the nanoscale. Finite element analysis suggests that the wall-thickness-dependent strength of nanotubular ZnO originates from nanotubular structures formed on ligaments of np-Au