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High quantum yield triplets, populated by initially prepared excited singlets, are desired for various energy conversion schemes in solid working compositions like porous MOFs. However, a large disparity in the distribution of the excitonic center of mass, singlet‐triplet intersystem crossing (ISC) in such assemblies is inhibited, so much so that a carboxy‐coordinated zirconium heavy metal ion cannot effectively facilitate the ISC through spin‐orbit coupling. Circumventing this sluggish ISC, singlet fission (SF) is explored as a viable route to generating triplets in solution‐stable MOFs. Efficient SF is achieved through a high degree of interchromophoric coupling that facilitates electron super‐exchange to generate triplet pairs. Here we show that a predesigned chromophoric linker with extremely poor ISC efficiency (kISC) but ES1≥2ET1 ${{E}_{{S}_{1}}\ge {2E}_{{T}_{1}}}$ form triplets in MOF in contrast to the frameworks that are built from linkers with sizable kISC but ES1≤2ET1 ${{E}_{{S}_{1}}\le {2E}_{{T}_{1}}}$. This work opens a new photophysical and photochemical avenue in MOF chemistry and utility in energy conversion schemes. [ABSTRACT FROM AUTHOR]

High quantum yield triplets, populated by initially prepared excited singlets, are desired for various energy conversion schemes in solid working compositions like porous MOFs. However, a large disparity in the distribution of the excitonic center of mass, singlet‐triplet intersystem crossing (ISC) in such assemblies is inhibited, so much so that a carboxy‐coordinated zirconium heavy metal ion cannot effectively facilitate the ISC through spin‐orbit coupling. Circumventing this sluggish ISC, singlet fission (SF) is explored as a viable route to generating triplets in solution‐stable MOFs. Efficient SF is achieved through a high degree of interchromophoric coupling that facilitates electron super‐exchange to generate triplet pairs. Here we show that a predesigned chromophoric linker with extremely poor ISC efficiency (kISC) but ES1≥2ET1 ${{E}_{{S}_{1}}\ge {2E}_{{T}_{1}}}$ form triplets in MOF in contrast to the frameworks that are built from linkers with sizable kISC but ES1≤2ET1 ${{E}_{{S}_{1}}\le {2E}_{{T}_{1}}}$. This work opens a new photophysical and photochemical avenue in MOF chemistry and utility in energy conversion schemes. [ABSTRACT FROM AUTHOR]

Electronics made from biological materials are desirable for use in medical devices, biosensors, and soft robotics because they have properties inaccessible to current inorganic technologies. Here, a series of cationic peptides were developed to self‐assemble with the anionic porphyrin meso‐tetra(4‐sulfonatophenyl)porphine (TPPS4) into supramolecular light‐harvesting wires known as J‐aggregates were developed. In addition to quantifying the binding events between each peptide and TPPS4, we found co‐incubation with mixed peptides allowed TPPS4 to bridge two different peptides at their terminal porphyrin‐binding regions. The J‐aggregates formed on macroscopic scale in near quantitative yield within ~3 h and readily interconverted with the soluble monomers upon cycling the pH; to our knowledge, this is the first report of a peptide‐porphyrin system with such properties. This work has practical and conceptual relevance to the development of new bioelectronic materials. [ABSTRACT FROM AUTHOR]

Herein, we present a light‐gated protocell model made of plasmonic colloidal capsules (CCs) assembled with bacteriorhodopsin for converting solar energy into electrochemical gradients to drive the synthesis of energy‐storage molecules. This synthetic protocell incorporated an important intrinsic property of noble metal colloidal particles, namely, plasmonic resonance. In particular, the near‐field coupling between adjacent metal nanoparticles gave rise to strongly localized electric fields and resulted in a broad absorption in the whole visible spectra, which in turn promoted the flux of photons to bacteriorhodopsin and accelerated the proton pumping kinetics. The cell‐like potential of this design was further demonstrated by leveraging the outward pumped protons as "chemical signals" for triggering ATP biosynthesis in a coexistent synthetic protocell population. Hereby, we lay the ground work for the engineering of colloidal supraparticle‐based synthetic protocells with higher‐order functionalities. Light‐gated synthetic protocells were built with plasmonic colloidal capsules and bacteriorhodopsin for solar‐driven proton gradient generation and communication‐mediated ATP synthesis. The impact of the colloidal particles' plasmon resonance on the performance of the cytomimetic system was also studied. [ABSTRACT FROM AUTHOR]

Discusses the fabrication and electrical performance of an all refractory niobium-nitrogen medium scale integrated circuit process. Fabrication of Josephson junctions; Plasma etching of in situ radio frequency sputter deposited trilayers of niobium-nitrogen/magnesium-oxygen/niobium-nitrogen; Use of a deposited silicon dioxide film for wiring and resistor insulation.

Entropy maximising spatial interaction models have been widely exploited in a range of disciplines and applications: from trade and migration flows to the spread of riots and the understanding of spatial patterns in archaeological sites of interest. When embedded into a dynamic system and framed in the context of a retail model, the dynamics of centre growth poses an interesting mathematical problem, with bifurcations and phase changes, which may be addressed analytically. In this paper, we present some analysis of the continuous retail model and the corresponding discrete version, which yields insights into the effect of space on the evolving system, and an understanding of why certain retail centres are more successful than others. The slowly developing growths and the fast explosive growths that are of particular concern are explained in detail. [ABSTRACT FROM PUBLISHER]

Designed peptide conjugates molecules are used to direct the synthesis and assembly of gold nanoparticles into complex 1D nanoparticle superstructures with various morphologies. Four peptide conjugates, each based on the gold-binding peptide (AYSSGAPPMPPF; PEPAu), are prepared: C12H23O-AYSSGAPPMPP ( 1), C12H23O-AYSSGAPPMPPF ( 2), C12H23O-AYSSGAPPMPPFF ( 3), and C12H23O-AYSSGAPPMPPFFF ( 4). The affect that C-terminal hydrophobic F residues have on both the soft-assembly of the peptide conjugates and the resulting assembly of gold nanoparticle superstructures is examined. It is shown that the addition of two C-terminal F residues ( 3) leads to thick, branched 1D gold nanoparticle superstructures, whereas the addition of three C-terminal F residues ( 4) leads to bundling of thin 1D nanoparticle superstructures. [ABSTRACT FROM AUTHOR]

Background: Ventilated patients receiving intensive care are at significant risk of acquiring a ventilator-associated pneumonia that is associated with significant morbidity and mortality. Despite intensive research, it is still unclear why Pseudomonas aeruginosa, a microbe that rarely causes pneumonia outside of intensive care, is responsible for so many of these infections.Methods: We investigated whether medications frequently prescribed to patients in the ICU, the catecholamine inotropes, were affecting the growth and virulence of P aeruginosa . Effects of clinically attainable concentrations of inotropes on P aeruginosa pathogenicity were explored using in vitro growth and virulence assays and an ex vivo model of infection using ciliated human respiratory epithelium.Results: We found that inotropes were potent stimulators of P aeruginosa growth, producing upto 50-fold increases in bacterial numbers via a mechanism involving inotrope delivery of transferrin-ron,internalization of the inotrope, and upregulation of the key pseudomonal siderophore pyoverdine.Inotropes also markedly increased biofilm formation on endotracheal tubing and enhanced the biofilm production and toxicity of P aeruginosa in its interaction with respiratory epithelium.Importantly, catecholamine inotropes also facilitated the rapid recovery of P aeruginosa from tobramycin antibiotic challenge. We also tested out the effect of the inotropes vasopressin and phenylephrine on the growth and virulence of P aeruginosa and found that, in contrast to the catecholamines,these drugs had no stimulatory effect.Conclusions: Collectively, our results suggest that catecholamine inotrope-bacterial interactions may be an unexpected contributory factor to the development of P aeruginosa -ventilator-associated pneumonia. [ABSTRACT FROM AUTHOR]

An UV-visible spectrometer for measuring absorbance and dichroism of Langmuir monolayers under in situ conditions is described. The spectrometer utilizes a stand-alone multipass sensor, which is placed in a Langmuir trough and coupled with light source and spectrometer head via fiber optics. Implementation of the multipass scheme in the absorbance sensor makes it possible to obtain reliable quantitative spectroscopic data of the Langmuir monolayers with absorbance as low as 1 mOD. Such high sensitivity makes the developed sensor very useful for UV-visible spectral studies of a wide variety of chromophores. The new technique was applied to several model systems: fatty acid monolayers containing amphiphilic dyes DiI or BODIPY and also a monolayer of a synthetic amphiphilic porphyrin-binding peptide BBC16. Implementation of UV-visible absorbance spectroscopy measurements in situ together with x-ray scattering technique was used to confirm the bound state of the chromophore, and determine the exact position of the latter in the peptide matrix. Fiber optics design of the spectrometer provides portability and compatibility with other experimental techniques making it possible to study samples with a geometry unsuitable for conventional spectroscopic measurements and located in experimental environments with spatial limitations, such as synchrotron x-ray scattering stations. [ABSTRACT FROM AUTHOR]

The stable carbon and nitrogen isotopic composition of urine and milk samples from cattle under different feeding regimes were analysed over a period of six months. The isotope ratios were measured with isotope ratio mass spectrometry (IRMS). The δ 13C values of milk and urine were dependent on different feeding regimes based on C3 or C4 plants. The δ 13C values are more negative under grass feeding than under maize feeding. The δ 13C values of milk are more negative compared to urine and independent of the feeding regime. Under grass feeding the analysed milk and urine samples are enriched in 13C relative to the feed, whereas under maize feeding the 13C/12C ratio of urine is in the same range and milk is depleted in 13C relative to the diet. The difference between the 15N/14N ratios for the two feeding regimes is less pronounced than the 13C/12C ratios. The δ 15N values in urine require more time to reach the new equilibrium, whereas the milk samples show no significant differences between the two feeding regimes. [ABSTRACT FROM AUTHOR]

Modern dentistry demands continuous professional development. This paper reports part of a project to develop a lifelong learning tool known as a progress file for members of the dental team. The aim is to elucidate the views of dentists and dental therapists on the potential use at work of a progress file. Consultations were conducted with an opportunistic sample of 15 dentists and 32 dental therapists. Twenty eight dental therapists trialled the prototype for 6 months and 15 dentists appraised it. A progress file that addresses the needs of both employers and employees has potential to help all members of the dental team meet the demands of lifelong learning.

Studies methods used to tackle a common pedagogic problem in medical and dental education in Great Britain. Teaching and learning methods.

Overuse syndrome, a condition of pain and loss of function in muscle groups and ligaments through excessive use, is common in musicians. In this series, the less serious cases of the disorder have been successfully treated by a modification of physical activity while allowing the musician to continue to play. The more serious cases were treated by a radical rest programme, first described last century, usually up to 12 months, until the patient is pain free and the muscles and ligaments are no longer tender. Performance is then very gradually resumed. The criterion for total success is a return to music performance free of pain with sustainable practice habits. [ABSTRACT FROM AUTHOR]

Two British secondary schools (one a specialist music school) were surveyed to assess the prevalence of upper limb pain among specialist music students compared with students in a regular school setting. Female students tended to report pain more often than male students, but for both significantly higher prevalence was found in the music school. Pain in the regular school was most often attributed to writing, whereas in the music school it was associated with the playing of all instruments, but most particularly with cello, clarinet, and flute. Music students reported long hours of practice, but it appeared that the intensity of practice may be more important as a determinant of pain than the total hours spent practising. The results of the study are in substantial agreement with those previously published from Australia and North America. On the balance of probabilities the pain is due to overuse syndrome, which is very common in musicians and well known in writers. [ABSTRACT FROM PUBLISHER]

We describe an apparatus that enables mass spectral analysis of the reacting chemical mixtures that drive detonation. Laboratory-scale (∼0.1 g) explosive pellets are detonated in a high-vacuum chamber, and rapid cooling by adiabatic free expansion quenches the chemical reactions. The instrument records a series of 95 mass spectra of the quenched reaction mixtures from one pellet. The spectra cover the mass range m=1 to m=300 and are recorded every 12 μs, which provides a mass analysis for every 20 μm of the detonation wave. This expansion of the time scale occurs because after expansion a 20-μm layer takes 12 μs to pass the mass spectrometer ionizer. The series of spectra give a molecular characterization of the chemical processes that drive detonation. [ABSTRACT FROM AUTHOR]

Fibroblasts for nifedipine-induced fibrotic gingiva (NFG) have ben characterized with respect to several cellular functions which could contribute to the characteristic clinical overgrowth of the gingival collagen synthesis and breakdown, glycosaminoglycan production, fibronectin synthesis, and proliferation. Histologic examination of NFG tissue revealed a hyperplastic epithelium with elongated, branched rete pegs. The connective tissue consisted of densely-packed collagen fibers and numerous enlarged fibroblasts, as well as regions of thinner, disorganized collagen fibers in the vicinity of scattered inflammatory and mast cells. Results of in vitro experiments showed that the fibroblast strains from the fibrotic gingiva (NFG) produced significantly greater amounts of collagen and lower levels of collagenase activity when compared to age-and sex-matched normal human gingival fibroblast strains. The NFG fibroblasts did not produce significantly greater amounts of fibronectin, and their level of glycosaminoglycan production was less than that of the normal fibroblasts. The NFG fibroblasts did not proliferate significantly more rapidly than the normal fibroblast strains. These findings therefore show that there are defects in the regulation of collage production by NFG fibroblasts in vitro, and suggest that these alterations in collagen metabolism contribute to the over-deposition of collagen in this tissue, rather than hyperproliferation of the fibroblasts or through the production of increased amounts of fibronectin and glycosaminoglycans. [ABSTRACT FROM AUTHOR]

The present paper gives some more definite data concerning the motor and sensory abilities and attributes of the Australian aborigine, and at this level he or she does not differ much from the European. The difficulty of estimating mental abilities is discussed, and some data brought together which have some bearing on the question. [ABSTRACT FROM AUTHOR]

1. There is a lower percentage of positive Wassermanns in cases of malignant disease than in a similar population of non-malignant cases. If buccal cancers are excluded, the percentage is half that in non-malignant cases.2. Cancer of the tongue and buccal cavity, in which a high percentage of positive Wassermanns is found, is almost confined to males and is probably due less to syphilitic infection than to some factor such as smoking.3. There is a low percentage of syphilis in cancer of the digestive tract, except in cases of cancer of the stomach, and the incidence diminishes from mouth to anus.4. Syphilis does not appear to be a factor of importance in cancer of the glandular organs, nor, apart from the lip, in the production of cutaneous cancer.5. In general, from the above figures there is no evidence that syphilis plays any direct or very important part in the production of cancer. [ABSTRACT FROM PUBLISHER]

The purple membrane (PM) isolated from the bacteria Halobacterium salinarum (H. salinarum) arranges the transmembrane proton pump bacteriorhodopsin (bR) in a 2D hexagonal crystalline lattice. Here, PM sheets containing native bR bend into tube‐like structures with open edges under acidic pH conditions. When decorated with gold nanoparticles (AuNPs), these same PM sheets yield a sealed tube assembly. Upon Rhodamine B (Rh B) sequestration inside the sealed tube, a dramatic decrease in Rh B fluorescence lifetime (τf) from 1.5 ns (unencapsulated) to 14 ps (encapsulated) is observed. The dramatic decrease in lifetime is attributed to energy transfer between AuNPs and Rh B. Subsequent release from the AuNP–PM capsules triggered by an increase in pH shows that 93% of Rh B is recovered (τ = 14 min) due to the capsules' unfolding. The hybrid AuNP–PM material highlights the utility of multicomponent ensembles (i.e., lipid bilayer, protein array, and NPs) by demonstrating that complex, multistimuli 3D responses can lead to multiplexed functions such as controlling energy transfer in the confined, encapsulated state and breaking the energy pair via molecular release in response to a change in pH. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about tenosynovitis.