Metal-hydrides have been of great interest as one of the most promising materials for hydrogen storage applications. For widespread use, the most appropriate container and thermal management systems ...to minimise the time of absorption and desorption and maximise the amount of stored hydrogen must be designed. In recent years, many attempts have been made to identify the relationship between different operating and design variables and the resultant performance of metal-hydride systems. In this review, features of mathematical models of metal-hydride reactors including the assumptions, different applied equations and solution methods which have been developed in previous studies are presented. The evolution of the reactor geometries and configurations of cooling systems as well as different effective factors of metal-hydride performance are also discussed.
X-linked retinitis pigmentosa (XLRP) is genetically heterogeneous with two causative genes identified, RPGR and RP2. We previously mapped a locus for a severe form of XLRP, RP23, to a 10.71 Mb ...interval on Xp22.31-22.13 containing 62 genes. Candidate gene screening failed to identify a causative mutation, so we adopted targeted genomic next-generation sequencing of the disease interval to determine the molecular cause of RP23. No coding variants or variants within or near splice sites were identified. In contrast, a variant deep within intron 9 of OFD1 increased the splice site prediction score 4 bp upstream of the variant. Mutations in OFD1 cause the syndromic ciliopathies orofaciodigital syndrome-1, which is male lethal, Simpson-Golabi-Behmel syndrome type 2 and Joubert syndrome. We tested the effect of the IVS9+706A>G variant on OFD1 splicing in vivo. In RP23 patient-derived RNA, we detected an OFD1 transcript with the insertion of a cryptic exon spliced between exons 9 and 10 causing a frameshift, p.N313fs.X330. Correctly spliced OFD1 was also detected in patient-derived RNA, although at reduced levels (39%), hence the mutation is not male lethal. Our data suggest that photoreceptors are uniquely susceptible to reduced expression of OFD1 and that an alternative disease mechanism can cause XLRP. This disease mechanism of reduced expression for a syndromic ciliopathy gene causing isolated retinal degeneration is reminiscent of CEP290 intronic mutations that cause Leber congenital amaurosis, and we speculate that reduced dosage of correctly spliced ciliopathy genes may be a common disease mechanism in retinal degenerations.
Summary
The phenomenon of total internal reflection fluorescence (TIRF) was placed in the context of optical microscopy by Daniel Axelrod over three decades ago. TIRF microscopy exploits the ...properties of an evanescent electromagnetic field to optically section sample regions in the close vicinity of the substrate where the field is induced. The first applications in cell biology targeted investigation of phenomena at the basolateral plasma membrane. The most notable application of TIRF is single‐molecule experiments, which can provide information on fluctuation distributions and rare events, yielding novel insights on the mechanisms governing the molecular interactions that underpin many fundamental processes within the cell. This short review intends to provide a ‘one stop shop’ explanation of the electromagnetic theory behind the remarkable properties of the evanescent field, guide the reader through the principles behind building or choosing your own TIRF system and consider how the most popular applications of the method exploit the evanescent field properties.
We present multi-point in situ observations of a complex sequence of coronal mass ejections (CMEs) which may serve as a benchmark event for numerical and empirical space weather prediction models. On ...2010 August 1, instruments on various space missions, Solar Dynamics Observatory/Solar and Heliospheric Observatory/Solar-TErrestrial-RElations-Observatory (SDO/SOHO/STEREO), monitored several CMEs originating within tens of degrees from the solar disk center. We compare their imprints on four widely separated locations, spanning 120degrees in heliospheric longitude, with radial distances from the Sun ranging from MESSENGER (0.38 AU) to Venus Express (VEX, at 0.72 AU) to Wind, ACE, and ARTEMIS near Earth and STEREO-B close to 1 AU. Calculating shock and flux rope parameters at each location points to a non-spherical shape of the shock, and shows the global configuration of the interplanetary coronal mass ejections (ICMEs), which have interacted, but do not seem to have merged. VEX and STEREO-B observed similar magnetic flux ropes (MFRs), in contrast to structures at Wind. The geomagnetic storm was intense, reaching two minima in the Dst index (approximate-100 nT), and was caused by the sheath region behind the shock and one of two observed MFRs. MESSENGER received a glancing blow of the ICMEs, and the events missed STEREO-A entirely. The observations demonstrate how sympathetic solar eruptions may immerse at least 1/3 of the heliosphere in the ecliptic with their distinct plasma and magnetic field signatures. We also emphasize the difficulties in linking the local views derived from single-spacecraft observations to a consistent global picture, pointing to possible alterations from the classical picture of ICMEs.
An intrinsically microporous high surface area (772 m2 g–1) hexaazatrinaphthylene-based network polymer has been synthesized. Additionally, the material was postmodified via the introduction of ...palladium ions to determine the effect of metalation on the properties of the assembly. Both the unmodified as-synthesized and metal-modified polymers were characterized using elemental analysis, Fourier transform infrared spectroscopy, solid-state 13C cross-polarization-magic-angle spinning NMR spectroscopy, Brunauer–Emmett–Teller surface area analysis, X-ray photoelectron spectroscopy, X-ray diffraction analysis (XRD), small-angle X-ray scattering, and thermogravimetric analysis techniques. The hydrogen uptake capacities of these materials were determined for a wide range of pressures up to 2000 bar. The palladium functionalization changed the intermolecular chain distances in the polymer, enhanced the microporosity, and increased the hydrogen uptake at ambient temperature.
To determine whether patient reported outcomes improve after single stage versus two stage revision surgery for prosthetic joint infection of the hip, and to determine the cost effectiveness of these ...procedures.
Pragmatic, parallel group, open label, randomised controlled trial.
High volume tertiary referral centres or orthopaedic units in the UK (n=12) and in Sweden (n=3), recruiting from 1 March 2015 to 19 December 2018.
140 adults (aged ≥18 years) with a prosthetic joint infection of the hip who required revision (65 randomly assigned to single stage and 75 to two stage revision).
A computer generated 1:1 randomisation list stratified by hospital was used to allocate participants with prosthetic joint infection of the hip to a single stage or a two stage revision procedure.
The primary intention-to-treat outcome was pain, stiffness, and functional limitations 18 months after randomisation, measured by the Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) score. Secondary outcomes included surgical complications and joint infection. The economic evaluation (only assessed in UK participants) compared quality adjusted life years and costs between the randomised groups.
The mean age of participants was 71 years (standard deviation 9) and 51 (36%) were women. WOMAC scores did not differ between groups at 18 months (mean difference 0.13 (95% confidence interval -8.20 to 8.46), P=0.98); however, the single stage procedure was better at three months (11.53 (3.89 to 19.17), P=0.003), but not from six months onwards. Intraoperative events occurred in five (8%) participants in the single stage group and 20 (27%) in the two stage group (P=0.01). At 18 months, nine (14%) participants in the single stage group and eight (11%) in the two stage group had at least one marker of possible ongoing infection (P=0.62). From the perspective of healthcare providers and personal social services, single stage revision was cost effective with an incremental net monetary benefit of £11 167 (95% confidence interval £638 to £21 696) at a £20 000 per quality adjusted life years threshold (£1.0; $1.1; €1.4).
At 18 months, single stage revision compared with two stage revision for prosthetic joint infection of the hip showed no superiority by patient reported outcome. Single stage revision had a better outcome at three months, fewer intraoperative complications, and was cost effective. Patients prefer early restoration of function, therefore, when deciding treatment, surgeons should consider patient preferences and the cost effectiveness of single stage surgery.
ISRCTN registry ISRCTN10956306.
Hydrogen storage for off-grid power supply Gray, E.MacA; Webb, C.J.; Andrews, J. ...
International journal of hydrogen energy,
2011, 2011-01-00, 20110101, Letnik:
36, Številka:
1
Journal Article
Recenzirano
The use of intermittent renewable energy sources for power supply to off-grid electricity consumers depends on energy storage technology to guarantee continuous supply. Potential applications of ...storage-guaranteed systems range from small installations for remote telecoms, water-pumping and single dwellings, to farms and whole communities for whom grid connection is too expensive or otherwise infeasible, to industrial, military and humanitarian uses. In this paper we explore some of the technical issues surrounding the use of hydrogen storage, in conjunction with a PEM electrolyser and PEM fuel cell, to guarantee electricity supply when the energy source is intermittent, most typically solar photovoltaic. We advocate metal-hydride storage and compare its energy density to that of Li-ion battery storage, concluding that a significantly smaller package is possible with metal-hydride storage. A simple approach to match the output of a photovoltaic array to an electrolyser is presented. The properties required for the metal-hydride storage material to interface the electrolyser to the fuel cell are discussed in detail. It is concluded that relatively conventional Mischmetal-based AB
5 alloys are suitable for this application.
•Vulnerability assessments provide the basis for climate adaptation planning.•We assess the vulnerability of 240 cattle producers across Northern Australia.•Vulnerability is assessed using ...sensitivity to change and adaptive capacity.•We found that there were four main types of producers based on their vulnerability.•Only 16% of producers were recognized as not vulnerable to climate change.
Adaptation of agricultural industries to climate change will make a major difference to the extent of the impacts experienced as a result of climate change. Vulnerability assessments provide the basis for developing strategies to reduce social vulnerability and plan for climate adaptation. Primary industries have been identified as the most vulnerable industry sector globally. We review how primary producers might be socially vulnerable to climate change and develop a ‘vulnerability typology’ of cattle producers based on survey responses from 240 producers across northern Australia. We measured social vulnerability according to ten indicators of climate sensitivity (resource dependency) and four indicators of adaptive capacity. Using a K-means clustering analysis we identified four main ‘types’ of cattle producers. Type 1 producers (43%) were vulnerable because they had low strategic skills and low interest in changing behaviour. Mean age was 59 years old, they were weakly networked within the industry and businesses were small. Type II producers (41%) had low strategic skills, poorly managed risk and uncertainty, had medium sized businesses and were 51 years old on average. Only 16% of producers (Type III and IV) appeared to have resilience to change. Type III producers (13.4%) had a stronger psychological and financial buffer, were 52 years old on average, were well networked and managed or owned larger businesses. Type IV producers (2.6%) managed risk well, liked to experiment with options and were interested in change. They were 41 years old on average, managed extremely large properties, were well networked, perceived themselves as responsible for the future productivity of their land and were early adopters of new technology. By providing knowledge of the different ways in which people can be vulnerable to climate change, vulnerability assessments can enable decision-makers to prioritise their efforts, provide a basis for early engagement, and tailor a range of adaptation approaches to most effectively accommodate and support the divergent requirements of different “types” of resource-users.
Abstract The purpose of this study was to assess leg muscle quality and give a detailed description of leg muscle involvement in a series of Duchenne muscular dystrophy patients using quantitative ...MRI and strength measurements. Fatty infiltration, as well as total and contractile (not fatty infiltrated) cross sectional areas of various leg muscles were determined in 16 Duchenne patients and 11 controls (aged 8–15). To determine specific muscle strength, four leg muscle groups (quadriceps femoris, hamstrings, anterior tibialis and triceps surae) were measured and related to the amount of contractile tissue. In patients, the quadriceps femoris showed decreased total and contractile cross sectional area, attributable to muscle atrophy. The total, but not the contractile, cross sectional area of the triceps surae was increased in patients, corresponding to hypertrophy. Specific strength decreased in all four muscle groups of Duchenne patients, indicating reduced muscle quality. This suggests that muscle hypertrophy and fatty infiltration are two distinct pathological processes, differing between muscle groups. Additionally, the quality of remaining muscle fibers is severely reduced in the legs of Duchenne patients. The combination of quantitative MRI and quantitative muscle testing could be a valuable outcome parameter in longitudinal studies and in the follow-up of therapeutic effects.
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